Aggregate radiated power control for multi-band/multi-mode satellite radiotelephone communications systems and methods

(54) Title: SATELLITE RADIO TELEPHONE TELEPHONE COMMUNICATION SYSTEM AND METHOD, SATELLITE RADIO TELEPHONE PHONE SYSTEM, AUXILIARY TERRESTRIAL NETWORK AND FIRST TERRESTRIAL COMPONENT FOR A RATIO SYSTEM FOR A RATIO SYSTEM, AERIAL SYSTEM FOR A RATIO OF CONNECTION IN A SATELLITE RADIO TELEPHONE SYSTEM (30) Unionist Priority: 01/05/2003 us 60 / 467,100 (71) Depositor (s): Mobile Satellite Ventures, LP (US) (72) Inventor (s): PeterD. Karabinis (57) Abstract: SATELLITE RADIO TELEPHONE COMMUNICATION SYSTEM AND METHOD APPLIANCE AND METHOD FOR CONTROLLING A SATELLITE RADIO TELEPHONE SYSTEM, AUXILIARY TERRESTRIAL NETWORK AND A FIRST EARTH OF EMPLOYMENT SYSTEM TO EMPLOYEES A SATELLITE SERVICE OF CONNECTION IN A SATELLITE RADIO TELEPHONE SYSTEM. A satellite radiotelephone system includes a space-based component that is configured to communicate with multiple radiotelephones over multiple frequency bands and / or multiple air interfaces. An auxiliary terrestrial network is configured to communicate over land with multiple radiotelephones substantially across multiple frequency bands and / or substantially across multiple air interfaces. An aggregated radiated power controller is configured to limit an aggregated radiated power across multiple radiotelephones to a maximum aggregated radiated power.

(74) Attorney: Momsen, Leonardos & CIA (86) International Application: pctus2004 / 01254i of 4/14/2004 (87) International Publication: wo 2004/100501 of 18/11/2004

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“SATELLITE RADIOTELPHONE COMMUNICATION SYSTEM AND METHOD, APPLIANCE AND METHOD FOR CONTROLLING A SATELLITE RADIO TELEPHONE SYSTEM, AUXILIARY TERRESTRIAL NETWORK AND THE FIRST AUXILIARY LODGE SYSTEM FOR A RADIATELY, RADIATELY SYSTEM SATELLITE RADIO TELEPHONE SYSTEM ”

Cross Reference to Related Orders

This request claims the benefit of Provisional Application No. 60 / 467,100, filed on May 1, 2003, entitled Aggregate Radiated Power Control for Multi-Band / Multi-Mode Satellite Radiotelephone Communications Systems and Methods, which is assigned to the assignee of this application , the exhibition of which is hereby incorporated by reference in its entirety as if published completely here.

Field of the Invention

This invention relates to radiotelephone communication systems and methods, and more particularly to terrestrial and satellite cellular radiotelephone communication systems and methods.

Background of the Invention

Satellite radiotelephone communication methods and systems are widely used for radiotelephone communications. Satellite radiotelephone communication systems and methods generally employ at least one space-based component, such as one or more satellites that are configured to communicate wirelessly with a plurality of satellite radiotelephones.

A satellite radiotelephone communication system or method can use a single antenna beam covering an entire area served by the system. Alternatively, in cellular satellite radiotelephone communication systems and methods, multiple beams are provided, each of which can serve distinct geographic areas in the global service region, to collectively serve a global satellite footprint. Thus, a cellular architecture similar to that used in conventional terrestrial cellular radiotelephone systems and methods can be implemented in systems and methods based on cellular satellite. The satellite typically communicates with radiotelephones via a two-way communication path, with radiotelephone communication signals being communicated from the satellite to the radiotelephone via a lower link or routing link, and from the radiotelephone to the satellite via an upper link or I return.

The overall design and operation of cellular satellite radiotelephone systems and methods are well known to those of skill in the art, and need not be described further here. Furthermore, as used here, the term radiotelephone includes cellular and / or satellite radiotelephones with or without a multi-line display; Personal Communication System (PCS) terminals that can combine a radiotelephone with data processing, facsimile and / or data communication capabilities; Personal Digital Assistants (PDA) which may include a radio frequency transceiver and a radiolocator, Intemet / intranet access, Web browser, organizer, calendar and / or a global positioning system (GPS) receiver; and / or conventional laptop and / or palmtop computers or other appliances, which include a radio frequency transceiver. A radiotelephone can also be referred to here as a radio terminal.

Terrestrial networks can increase the availability, efficiency and / or economic viability of a cellular satellite radiotelephone system by reusing overland at least some of the frequency bands that are allocated to cellular satellite radiotelephone systems. In particular, it is known that it may be difficult for cellular satellite radiotelephone systems to reliably serve densely populated areas, because the satellite signal can be blocked by overhead structures and / or may not penetrate buildings. As a result, the satellite spectrum may be underutilized or may become unusable in such areas. Terrestrial reuse of at least some of the frequencies in a satellite band can reduce or eliminate this potential problem.

Furthermore, the capacity of the global system can be increased significantly by introducing terrestrial reuse of frequencies in a satellite band, as terrestrial frequency reuse can be much more dense than that of a single satellite system. In reality, capacity can be increased where it can be mainly needed, that is, densely populated / industrial / commercial areas. As a result, the global system can become much more economically viable, as it may be able to serve a much larger subscriber base.

An example of terrestrial reuse of satellite frequencies is described in US Patent 5,937,332 to the present inventor Karabinis, entitled Satellite Telecommunications Repeaters and Retransmission Methods, the exhibit of which is hereby incorporated by reference in its entirety as if published in its entirety on here. As described therein, satellite telecommunication repeaters are provided that receive, amplify and relay locally the bottom link signal received from a satellite, thereby increasing the effective bottom link margin in the vicinity of the satellite telecommunication repeaters and allowing for an increase penetration of upper and lower connection signals in buildings, foliage, transport vehicles, and other objects that can reduce the connection margin. Both portable and non-portable repeaters are provided. See summary of US Patent 5,937,332.

Finally, satellite radiotelephones for a satellite radiotelephone system or method having a terrestrial component within the same satellite frequency band and using substantially the same air interface for both terrestrial and satellite communications can be cost effective and / or aesthetically attractive. Conventional dual-band / dual-mode alternatives, such as the well-known dual-mode terrestrial / satellite radiotelephone systems Thuraya, Iridium and / or Globalstar, may duplicate some components, which can lead to increased cost, size and / or weight. radiotelephone. See US Patent 6,052,560 for the present inventor Karabinis, entitled Satellite System Utilizing a Plurality of Air Interface Standards and Method Employing Same.

In view of the foregoing discussion, there remains a need for systems and methods for terrestrial reuse of cellular satellite frequencies that can enable improved reliability, capacity, cost efficiency and / or aesthetic appeal for cellular satellite radiotelephone systems, methods and / or satellite radiotelephones.

Summary of the Invention

Some embodiments of the present invention provide satellite radiotelephone systems and communication methods in which a space-based component is configured to communicate with radiotelephones in a satellite footprint that is divided into a plurality of satellite cells. The space-based component is configured to communicate with a first radiotelephone in a first satellite cell via a first frequency band and / or a first air interface, and to communicate with a second radiotelephone in a second satellite cell through a second frequency band and / or a second air interface. In some embodiments, an auxiliary terrestrial network is also provided that is configured to communicate by land with the first radiotelephone substantially through the first frequency band and / or substantially by the first air interface, and to communicate by land with the second radiotelephone substantially through the second frequency band and / or substantially through the second air interface.

In other embodiments, satellite radiotelephone systems and methods include a space-based component that is configured to communicate with a first radiotelephone via a first frequency band and / or a first air interface, and with a second radiotelephone via a second frequency band and / or a second air interface. An auxiliary terrestrial network is configured to communicate overland with the first radiotelephone substantially through the first frequency band and / or substantially through the first air interface, and to communicate overland with the second radiotelephone substantially through the second frequency band. frequency and / or substantially through the second air interface. The first and second radiotelephones can be in the same satellite cell or in different satellite cells.

In any of the above embodiments, the terrestrial auxiliary network may include a first terrestrial auxiliary component that is configured to communicate by terrestrial path with the first radiotelephone substantially through the first frequency band and / or substantially through the first air interface, and a second auxiliary terrestrial component that is configured to communicate by land with the second and / or first radiotelephone substantially through the second frequency band and / or substantially through the second air interface. In some embodiments, the first auxiliary ground component is in the first satellite cell, and the second auxiliary ground component is in the second satellite cell. In other embodiments, they are in the same satellite cell. In still other embodiments, the first auxiliary ground component is operated by a first wireless operator and the second auxiliary ground component is operated by a second wireless operator.

In addition, in any of the embodiments described above, the auxiliary terrestrial network may include a first portion that is configured to communicate by land with the first radiotelephone substantially through the first frequency band and / or substantially through the first air interface, and a second portion that is configured to communicate overland with the second and / or first radiotelephone substantially through the second frequency band and / or substantially through the second air interface. In some embodiments, the first portion is operated by a first wireless operator and the second portion is operated by a second wireless operator.

In any of the above embodiments, a connection point can also be provided that is configured to communicate with the space-based component via a feeder connection. The feeder connection is configured to carry communication between the space-based component and the first and second radiotelephones. In some embodiments, the feeder connection includes the first air interface and the second air interface.

Still other embodiments of the present invention control the radiated power aggregated by radiotelephones in multi-band / multi-mode satellite radiotelephone communication methods. Specifically, some embodiments of the present invention provide satellite radiotelephone systems in which a space-based component is configured to communicate with a plurality of radiotelephones through a plurality of frequency bands and / or a plurality of air interfaces. An auxiliary terrestrial network is configured to communicate over land with the plurality of radiotelephones substantially through the plurality of first frequency bands and / or substantially through the plurality of air interfaces. An aggregated radiated power controller is configured to limit an aggregated radiated power by the plurality of radiotelephones to a maximum aggregated radiated power. Analog irradiated aggregate power control methods r 5 can also be provided.

Accordingly, some embodiments of the present invention allow space-based communication to be added to a first terrestrial network that is configured to communicate with a first radiotelephone via a first frequency band and / or a first air interface, and a second terrestrial network that is configured to communicate with a second radiotelephone through a second frequency band and / or a second air interface. These embodiments provide communication between a space-based component and the first radiotelephone substantially through the first frequency band and / or the first air interface and between the space-based component and the second radiotelephone substantially through the second frequency band and / or substantially from the second air interface. It will be understood that the embodiments of the present invention can be provided as systems and / or methods.

Brief Description of Drawings

Figure 1 is a schematic diagram of cellular radiotelephone systems and methods according to embodiments of the invention.

Figure 2 is a block diagram of adaptive interference reducers according to embodiments of the present invention.

Figure 3 is a spectrum diagram that illustrates frequency allocations of satellite L band.

Figure 4 is a schematic diagram of cellular satellite systems and methods according to other embodiments of the present invention.

Figure 5 illustrates time division duplex frame structures according to embodiments of the present invention.

Figure 6 is a block diagram of auxiliary ground component architectures according to embodiments of the invention.

Figure 7 is an architecture block diagram of reconfigurable radiotelephones according to embodiments of the invention.

Figure 8 graphically illustrates the mapping of monotonically decreasing power levels to frequencies according to embodiments of the present invention.

Figure 9 illustrates an ideal cell that is mapped to three regions of power and three associated carrier frequencies according to embodiments of the invention.

Figure 10 describes a realistic cell that is mapped to three power regions and three associated carrier frequencies according to embodiments of the invention.

Figure 11 illustrates two or more contiguous intervals in a frame that are unoccupied according to embodiments of the present invention.

Figure 12 illustrates the loading of two or more contiguous intervals with lower power transmissions according to embodiments of the present invention.

Figure 13 is a block diagram of satellite radiotelephone systems and methods according to some embodiments of the invention.

Figure 14 is a schematic diagram of terrestrial frequency reuse of satellite frequencies according to some embodiments of the invention.

Figure 15 is a block diagram of radiotelephones according to some embodiments of the invention.

Figure 16 is a schematic diagram of satellite radiotelephone systems and methods according to some embodiments of the invention.

Figure 17 is a schematic diagram of satellite radiotelephone systems and methods according to some embodiments of the invention.

Figure 18 is a schematic diagram of satellite radiotelephone systems and methods including control of aggregated radiated power according to some embodiments of the present invention.

Figure 19 is a schematic diagram of an auxiliary terrestrial network including systems and methods that can increase the connection margins according to some embodiments of the present invention.

Detailed Description of Preferred Embodiments

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. However, this invention should not be interpreted as limited to the embodiments published here. Instead, these embodiments are provided in such a way that this exposure will be thorough and complete, and will completely extend the invention to those skilled in the art. Same numbers refer to the same elements everywhere.

Figure 1 is a schematic diagram of cellular satellite radiotelephone systems and methods according to embodiments of the invention. As shown in Figure 1, these cellular satellite radiotelephone systems and methods 100 include at least one Space Based Component (SBC) 110, such as a satellite. Space-based component 110 is configured to transmit wireless communication to a plurality of radiotelephones 120a, 120b in a satellite footprint including one or more satellite radiotelephone cells 130-130 through one or more frequencies f_D satellite radiotelephone routing connection (bottom connection). The space-based component 110 is configured to receive wireless communication from, for example, a first radiotelephone 120a in the radiote cell satellite 130 through a satellite radiotelephone return link fu (top link). An auxiliary terrestrial network, including at least one auxiliary terrestrial component 140, ~ 5 which can include an antenna 140a and an electronics system 140b (for example, at least one antenna 140a and at least one electronics system

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140b), is configured to receive wireless communication from, for example, a second radiotelephone 120b in the radiotelephone cell 130 through the top link frequency of a satellite radiotelephone, denoted fu, which can be the same as f_v. Thus, as illustrated in Figure 1, the radiotelephone 120a may be communicating with the space-based component 110 while the radiotelephone 120b may be communicating with the auxiliary terrestrial component 140. As shown in Figure 1, the space-based component 110 also undesirably receives the wireless communication from the second radiotelephone 120b in the satellite radiotelephone cell 130 through the frequency of the satellite radiotelephone fu as interference. More specifically, a potential interference path is shown at 150. In this potential interference path 150, the return link signal from the second radiotelephone 120b on the carrier frequency fu interferes with satellite communication. This interference would generally be stronger when fu⁼ fu, because in that case, the same return link frequency would be used for space-based component and auxiliary terrestrial component communication through the same satellite radiotelephone cell, and no spatial discrimination between satellite radiotelephone cells would appear to exist.

Still referring to Figure 1, embodiments of satellite radiotelephone systems / methods 100 may include at least one connection point 160, which may include an antenna 160a and an electronics system 160b, which may be connected to other networks 162 including networks terrestrial radiotelephone and / or other networks. The connection point 160 also communicates with the space-based component 110 via a satellite feeder connection 112. The connection point 160 also communicates with the auxiliary terrestrial component 140, generally via a terrestrial connection 142.

Still referring to Figure 1, an Interference Reducer (IR) 170a can also be provided at least partially in the auxiliary terrestrial component electronics system 140b. Alternatively or in addition, an interference reducer 170b can be provided at least partially in the connection point electronics system 160b. In still other alternatives, the jammer may be provided at least partially in other components of the cellular satellite system / method 100 instead of or in addition to jammer 170a and / or 170b. The interference reducer is responsive to the space-based component 110 and the auxiliary terrestrial component 140, and is configured to reduce the interference from wireless communication that is received by the space-based component 110 and is at least partially generated by the second radiotelephone 120b on satellite radiotelephone cell 130 through fu satellite radiotelephone frequency. The interference reducer 170a and / or 170b uses the wireless communication frequency fu that is intended for the auxiliary ground component 140 of the second radiotelephone 120b in the satellite radiotelephone cell 130 using the satellite radiotelephone frequency fu to communicate with the auxiliary ground component 140.

In embodiments of the invention, as shown in Figure 1, the auxiliary terrestrial component 140 is generally closer to the first and second radiotelephones 120a and 120b, respectively, than is the space-based component 110, such that the wireless communication of the second radiotelephone 120b is received by auxiliary ground component 140 before being received by space-based component 110. The interference reducer 170a and / or 170b is configured to generate an interference cancellation signal including, for example, at least one delayed replica of the wireless communication from the second radiotelephone 120b that is received by the auxiliary ground component 140, and to subtract the delayed replica r 5 of the wireless communication of the second radiotelephone 120b which is received by the auxiliary terrestrial component 140 of the wireless communication which is received from the space-based component 110. The interference reduction signal can be transmitted from the auxiliary ground component 140 to the connection point 160 via connection 142 and / or using other conventional techniques.

Thus, adaptive interference reduction techniques can be used at least partially to cancel the interference signal, so that the same, or a nearby, satellite radio superior link frequency can be used in a given cell for radiotelephone communication. 120 with satellite 110 and auxiliary ground component 140. Therefore, all frequencies that are assigned to a given cell 130 can be used by both radiotelephone communication 120 with the space-based component 110 and with the auxiliary terrestrial component 140. Conventional systems can prevent terrestrial reuse of frequencies within a given satellite cell being used within the satellite cell for satellite communication.

Conventionally stated differently, only frequencies used by other satellite cells can be candidates for terrestrial reuse within a given satellite cell. Spatial isolation from beam to beam that is provided by the satellite system was relied on to reduce or minimize the level of interference from terrestrial operations in satellite operations. In sharp contrast, embodiments of the invention may use an interference reducer to allow all frequencies assigned to a satellite cell to be used over land and for satellite radiotelephone communication.

Embodiments of the invention according to Figure 1 can arise from an embodiment that the return link signal from the second radiotelephone 120b in fu will generally be received and processed by the auxiliary terrestrial component 140 much earlier relative to the time when it will arrive at the connection point of satellite 160 of the space-based component 110 through interference path 150. Therefore, the interference signal at the satellite connection point 160b can be at least partially canceled. Thus, as shown in Figure 1, an interference cancellation signal, such as the demodulated auxiliary ground component signal, can be sent to satellite connection point 160b by the interference reducer 170a on the auxiliary ground component 140, for example using the connection 142. In the interference reducer 170b at the connection point 160b, a weighted (amplitude and / or phase) replica of the signal can be formed using, for example, adaptive cross filter techniques that are well known to those skilled in the art. Then, a transverse filter output signal is subtracted from the received satellite signal aggregated at fu frequency containing desired signals as well as interference. Thus, interference cancellation does not need to degrade the signal-to-noise ratio of the desired signal at connection point 160, because a regenerated (noise-free) terrestrial signal, for example as regenerated by auxiliary terrestrial component 140, can be used to execute suppression of interference.

Figure 2 is a block diagram of embodiments of adaptive interference cancellers that can be located on auxiliary ground component 140, at connection point 160, and / or on another component of the cellular radiotelephone system 100. As shown in Figure 2, a or more control algorithms 204, known to those skilled in the art, can be used to adaptively adjust the coefficients of a plurality of transverse filters 202a-202n. Adaptive algorithms, such as Mean Minimum Square Error (LMSE), Kalman, Fast Kalman, Forced to Zero and / or various combinations of them or other techniques can be used. It will be understood by those skilled in the art that the architecture of Figure 2 can be used with an LMSE algorithm. However, it will be understood by those skilled in the art that conventional architectural modifications can also be made to facilitate other control algorithms.

Additional embodiments of the invention will now be described with reference to Figure 3, which illustrates L-band frequency allocations including routing connections and cellular radiotelephone system return connections. As shown in Figure 3, the ground space L band forward link (bottom link) frequencies are designated from 1525 MHz to 1559 MHz. The frequencies of the L-band return link (top link) from ground to space occupy the 1626.5 MHz to 1660.5 MHz band. Between the forward and return L-band connections is the GPS radio navigation band. / GLONASS (from 1559 MHz to 1605 MHz).

In the following detailed description, GPS / GLONASS will be referred to simply as GPS for the sake of brevity. Furthermore, the acronyms ATC and SBC will be used for the auxiliary ground component and the space-based component, respectively, for the sake of brevity.

As is known to those skilled in the art, GPS receivers can be extremely sensitive since they are designed to operate on very weak spread-spectrum radio navigation signals arriving in the land from a constellation of GPS satellites. As a result, GPS receivers can be highly susceptible to in-band interference. ATCs that are configured to radiate L-band frequencies in the routing satellite band (1525 to 1559 MHz) can be designed with very high-band out-of-band emission filters to satisfy the desires of spurious out-of-band GPS emissions.

Referring again to Figure 1, some embodiments of the invention can provide systems and methods that can allow an ATC • 5 140 to be configured in one of at least two modes. According to a first mode, which can be a standard mode and can provide more i

high, ATC 140 transmits to radiotelephones 120 over the frequency range 1525 MHz to 1559 MHz, and receives transmissions from radiotelephones 120 in the frequency range 1626.5 MHz to 1660.5 MHz, as shown in Figure 3. In contrast , in a second mode of operation, ATC 140 transmits wireless communication to radiotelephones 120 over a modified range of satellite band forward link (bottom link) frequencies. The modified range of satellite band forward link frequencies can be selected to reduce, compared to the unchanged range of satellite band forward link frequencies, interference with wireless receivers such as GPS receivers operating outside the range of satellite bandwidth routing link frequencies.

Many modified bands of satellite band forward link frequencies can be provided according to embodiments of the present invention. In some embodiments, the modified range of satellite band forward link frequencies may be limited to a subset of the original range of satellite band forward link frequencies, thus to provide a guard band of forward link frequencies of unused satellite band. In other embodiments, all satellite bandwidth link frequencies are used, but wireless communication to radiotelephones is modified in a way to reduce interference with wireless receivers that operate outside the bandwidth link frequency range. satellite band. Combinations and sub-combinations of these and / or other techniques can also be used, as will be described below.

It will also be understood that embodiments of the invention that will now be described with reference to Figures 4-12 will be described in terms of multi-mode ATCs 140, which can operate in a first standard mode using the standard routing and return links of Figure 3, and in a second or alternate mode using a modified range of satellite band forward link frequencies and / or a modified range of satellite band return link frequencies.

These multi-mode ATCs can operate in the second, non-standard mode, as long as desired, and can be switched to standard mode otherwise. However, other embodiments of the present invention need not provide multiple mode ATCs but, instead, can provide ATCs that operate using the modified range of forward link frequencies and / or satellite band return link.

Embodiments of the invention will now be described, in which an ATC operates with an SBC that is configured to receive wireless communication from radiotelephones over a first range of satellite band back-up frequencies and to transmit wireless communication to radiotelephones via a second range of satellite band forward link frequencies that is spaced apart from the first range. According to these embodiments, the ATC is configured to use at least one duplex frequency per time division to transmit wireless communication to the radiotelephones and to receive wireless communication from the radiotelephones at different times. In particular, in some embodiments, the at least one duplex frequency per time division that is used to transmit wireless communication to the radiotelephones and to receive wireless communication from the radiotelephones at different times, includes a frame including a plurality of intervals. At least one first of the intervals is used to transmit wireless communication to the radiotelephones and at least one second of the intervals is used to receive wireless communication from the radiotelephones. Thus, in some embodiments, ATC transmits and receives, in Time Division Duplex (TDD) mode, using frequencies from 1626.5 MHz to 1660.5 MHz. In some embodiments, all ATCs across the entire network may have declared configuration / reconfiguration flexibility. In other embodiments, only a few ATCs can be reconfigurable.

Figure 4 illustrates satellite systems and methods 400 according to some embodiments of the invention, including an ATC 140 communicating with a radiotelephone 120b using a fu carrier frequency in TDD mode. Figure 5 illustrates an embodiment of a TDD frame structure. Assuming full-rate GSM (eight time slots per frame), up to four full-duplex voice circuits can be supported by a TDD carrier. As shown in Figure 5, ATC 140 transmits to radiotelephone 120b via, for example, time slot number 0. Radiotelephone 120b receives and responds back to ATC 140 via, for example, time slot number 4. Time slot numbers 1 and 5 can be used to establish communication with another radiotelephone, and so on.

A Broadcast Control Channel (BCCH) is transmitted preferably from the ATC 140 in standard mode, using a carrier frequency below any guard band exclusion region. In other embodiments, a BCCH can also be defined using a TDD carrier. In any of these embodiments, radio telephones in idle mode, through the established GSM methodology, can monitor BCCH and receive system level and radiolocation information. When a radiotelephone is radiolocated, the system decides which type of resource to allocate to the radiotelephone in order to establish the communication link. Any type of resource is allocated to the radiotelephone communication channel (TDD mode or standard mode), the information is communicated to the radiotelephone, for example as part of the call initiation routine, and the radiotelephone is configured accordingly.

It may be difficult for the TDD mode to co-exist with the standard mode through the same ATC, due, for example, to the ATC receptor LNA stage. In particular, assuming a mixture of GSM carriers in a standard way and TDD through the same ATC, during the part of the frame when TDD carriers are used to serve the routing link (when ATC is transmitting TDD) enough energy can leak at the receiver forwarding end of the same ATC to desensitize its LNA stage. Techniques can be used to suppress the ATC energy transmitted through the 1600 MHz portion of the band to desensitize the ATC receptor LNA, and thereby allow mixed standard and TDD frames. For example, isolation between departure and arrival ATC routing ends and / or loss of antenna system return can be increased or maximized. A switchable band-reject filter can be placed in front of the

LNA. This filter would be switched on the receiver chain (before the LNA) during the part of the frame when the ATC is transmitting TDD, and switched off for the rest of the time. An adaptive interference canceller can be configured in RF (before the LNA stage). If such techniques are used, suppression of the order of 70 dB can be achieved, which can allow mixed mode and standard TDD frames. However, the complexity and / or cost of ATC may increase.

Thus, although ATC LNA desensitization can be reduced or eliminated, it can use significant special engineering and attention and the effort may not be economically viable. Other embodiments, therefore, can keep pure TDD from TDD ATCs, with the exception, perhaps, of the carrier of BCCH that cannot be used for traffic, but only to broadcast through the first part of the frame, consistent with the TDD protocol. In addition, Random Access Channel (RACH) saves can be timed so that they reach the ATC during the second half of the TDD frame. In some embodiments, all TDD ATCs can be equipped to enable reconfiguration in response to a command.

It is well recognized that during data communication or other applications, the forward link can use transmissions at higher rates than the return link. For example, in web browsing with a radiotelephone, mouse clicks and / or other user selections are typically transmitted from the radiotelephone to the system. The system, however, in response to a user selection, may have to send large data files to the radiotelephone. Consequently, other embodiments of the invention can be configured to enable the use of an increased or maximum number of time slots per frame of the forwarding GSM carrier, to provide a higher lower link data rate to the radio telephones.

Thus, when a carrier frequency is configured to provide service in TDD mode, a decision can be made on how many intervals will be allocated to serve the forward link, and how many will be dedicated to the return link. Whatever the decision, it may be desirable to be adhered to by all TDD carriers used by ATC, in order to reduce or avoid the LNA desensitization problem described above. In voice communication, the partition between forward and return link intervals can be done in the middle of the frame as voice activity is typically statistically symmetrical in a bidirectional manner. Consequently, triggered by voice, the center of the frame can be where the TDD partition is taken.

To increase or maximize the routing link processing in data mode, data mode TDD carriers according to embodiments of the invention can use one or more spectrally efficient modulations and / or protocols, such as modulation and / or EDGE protocol, in the routing link intervals. The return link intervals can be based on a spectrally less efficient modulation and / or protocol such as GPRS modulation and / or protocol (GMSK). EDGE modulation / protocol and GPRS modulation / protocol are well known to those of skill in the art, and need not be described further here. Given an EDGE forwarding / GPRS return TDD carrier strategy, up to (3 84/2) = 192 kbps can be supported on the forward link, while on the return link, the radiotelephone can transmit up to (115/2 ) «64 kbps.

In other embodiments, it is also possible to allocate six slots from a frame of eight slots for the routing link and only two for the return link. In these embodiments, for voice services, given the statistically symmetrical nature of the voice, the callback vocoder may need to be comparable with quarter rate GSM, while the forward call vocoder may operate in full rate GSM, for produce six full duplex voice circuits per GSM TDD mode carrier (a 25% voice capacity penalty). Subject to this non-symmetric splitting strategy, data rates of up to (384) (6/8) = 288 kbps can be achieved on the routing link, with up to (115) (2/8) «32 kbps on the return link .

Figure 6 describes an ATC architecture according to embodiments of the invention, which can lead to automatic configuration between the two standard GSM and TDD GSM modes in command, for example, from a Network Operations Center (NOC) by a Base Station Controller (BSC). It will be understood that in these embodiments, an antenna 620 may correspond to the antenna 140a of Figures 1 and 4, and the rest of Figure 6 may correspond to the electronics system 140b of Figures 1 and 4. If a • 5 reconfiguration command for a particular carrier, or set of carriers, occurs while the carriers are active and are supporting traffic, then via the Bandwidth Signaling Associated Control Channel (FACCH), all affected radio telephones can be notified to also reconfigure and / or switch to new features. If carriers are reconfigured from TDD mode to standard mode, automatic reassignment of carriers to the appropriate standard ATCs, based, for example, on capacity demand and / or reuse pattern can be initiated by the NOC. If, on the other hand, carriers are reconfigured from standard mode to TDD mode, automatic reassignment to ATCs from

Appropriate TDDs can happen in charge of the NOC.

Still referring to Figure 6, a key 610 can remain closed when the carriers are to be demodulated in standard mode. In TDD mode, this switch 610 can be open during the first half of the frame, when the ATC is transmitting, and closed during the second half of the frame, when the ATC is receiving. Other embodiments can also be provided.

Figure 6 assumes N transceivers per ATC sector, where N can be as small as one, since a minimum of one carrier per sector is generally desired. Each transceiver is assumed to operate more than a pair of GSM carriers (when in standard mode) and can thus support up to eight full duplex voice circuits, neglecting the BCCH channel header. In addition, a pair of standard GSM carriers can support sixteen full-duplex voice circuits when in half-rate GSM mode, and up to thirty-two full-duplex voice circuits when in quarter-rate GSM mode .

When in TDD mode, the number of full duplex voice circuits can be reduced by a factor of two, assuming the same vocoder. However, in TDD mode, the voice service can be offered by: 5 half-rate GSM vocoder with almost imperceptible quality degradation, in order to maintain the invariable voice capacity. Figure 7 is a block diagram of a reconfigurable radiotelephone architecture that can communicate with the reconfigurable ATC architecture of Figure 6. In Figure 7, an antenna 720 is provided, and the rest of Figure 7 can provide embodiments of an electronics system for the radiotelephone.

It will be understood that the ability to reconfigure ATCs and radiotelephones according to embodiments of the invention can be obtained at a relatively small increase in cost. The cost can be mainly in Non-Recurring Engineering (NRE) cost to develop software.

Some recurring costs may also be incurred, however, since at least one additional RF filter and some electronically controlled keys can be used by ATC and radiotelephone. All other hardware / software can be common to GSM in standard mode and

TDD.

Referring now to Figure 8, other radiotelephone systems and methods according to embodiments of the invention will be described. In these embodiments, the modified second band of satellite band forward link frequencies includes a plurality of frequencies in the second band of satellite band forward link frequencies that are transmitted by ATCs to radio telephones at a power level, such as maximum power level, which decreases monotonically as a function of frequency (increasing). More specifically, as will be described below, in some embodiments, the second modified bandwidth link frequency band includes a subset of frequencies next to a first or second end of the bandwidth link frequency band which are transmitted by ATC to radiotelephones at a power level, such as a maximum power level, which monotonically decreases towards the first or second end of the second bandwidth of the satellite band forward link. In yet other embodiments, the first range of satellite band return link frequencies is contained in an L band of satellite frequencies above the GPS frequencies and the second range of satellite band forward link frequencies is contained in L band of satellite frequencies below GPS frequencies. The modified second band of satellite band forward link frequencies includes a subset of link band forward frequencies includes a subset of frequencies close to one end of the second band of link band forward frequencies adjacent to GPS frequencies that are transmitted by ATC to radiotelephones at a power level, such as a maximum power level, which monotonically decreases towards the end of the second range of satellite band forward link frequencies adjacent to the GPS frequencies.

Without being limited by any theory of operation, a theoretical discussion of mapping maximum ATC power levels to carrier frequencies according to embodiments of the present invention will now be described. Referring to Figure 8, let v = F (p) represent a mapping of the power domain (p) to the frequency range (v). The power (p) is the power that an ATC uses or should transmit in order to communicate confidently with a given radiotelephone. This power can depend on many factors such as the distance from the ATC radiotelephone, the blockage between the radiotelephone and the ATC, the level of multiple path fading in the channel, etc., and as a result, in general, it will change as a function of time. Consequently, the power used is generally determined in an adaptive way (iteratively) by closed-loop power control, between the radiotelephone and ATC.

The frequency (v) is the satellite carrier frequency that the ATC uses to communicate with the radiotelephone. According to embodiments of the invention, the F mapping is a monotonically decreasing function of the independent variable p. Consequently, in some embodiments, when the maximum ATC power increases, the carrier frequency that the ATC uses to establish and / or maintain the communication link decreases. Figure 8 illustrates an embodiment of a monotonically decreasing (stepped) continuous piece function. Other monotonic functions can be used, including linear and / or non-linear, constant and / or variable decreases. FACCH or Slow Associated Control Channel (SACCH) message transmission can be used in embodiments of the invention to facilitate adaptive and substantially real-time mapping.

Figure 9 describes an ideal cell according to embodiments of the invention, where, for purposes of illustration, three regions of power and three associated carrier frequencies (or sets of carrier frequencies) are being used to divide a cell. For simplicity, an ATC transmitter in the center of the idealized cell is assumed with no sectorization. In embodiments of Figure 9, the frequency (or set of frequencies) fi is taken substantially from the uppermost portion of the L-band forward link frequency set, for example from substantially close to 1559 MHz (see Figure 3). Correspondingly, the frequency (or set of frequencies) f_M it is taken substantially from the central portion of the L-band forward link frequency set (see Figure 3). In line with the above, the frequency (or set of frequencies) fo is taken from substantially the lowest portion of the L-band forward link frequencies, for example close to 1525 MHz (see Figure 3) ·

Thus, according to embodiments of Figure 9, if a radiotelephone is being served within the outermost ring of the cell, that radiotelephone is being served by fo frequency.

This radiotelephone, being within the most distant area of ​​the ATC, requested (presumably) maximum (or near maximum) power output from the ATC. In response to the request for maximum (or near maximum) output power, ATC uses its a priori knowledge of power to frequency mapping, such as a three-step ladder function in Figure 9. Thus, the ATC serves the radiotelephone with a low value frequency taken from the lowest portion of the set of mobile L-band routing link frequencies, for example, as close to 1525 MHz as possible. This, then, can provide additional protection for any GPS receiver unit that may be in the vicinity of the ATC.

Embodiments of Figure 9 can be considered idealized because they associate concentric ring areas with carrier frequencies (or sets of carrier frequencies) used by an ATC to serve its area. In reality, concentric ring areas will generally not be the case. For example, a radiotelephone may be close to the ATC that is serving it, but with significant blockage between the radiotelephone and the ATC due to a building. This radiotelephone, although relatively close to the ATC, can also request maximum (or near maximum) output power from the ATC. With this in mind, Figure 10 can describe a more realistic set of area contours that can be associated with the frequencies being used by the ATC to serve its territory, in accordance with embodiments of the invention. The fi frequency (or set of frequencies) can be reused in the immediately adjacent ATC cells due to the limited geographical extent associated with fi relative to the distance between cell centers. This can also be maintained for ÍmSe now referring to Figure 11, other second modified bands of satellite band forward link frequencies that can be used by ATCs according to embodiments of the present invention will now be described. In these embodiments, at least one frequency in the modified second band of satellite band forward link frequencies that are transmitted by the ATC to the radio telephones includes a frame including a plurality of intervals. In these embodiments, at least two contiguous intervals in the frame that is transmitted by the ATC to the radio telephones are left unoccupied. In other embodiments, three contiguous intervals in the frame that is transmitted by the ATC to the radio telephones are left unoccupied. In still other embodiments, at least two contiguous intervals in the frame that is transmitted by the ATC to the radiotelephones are transmitted at lower power than the remaining intervals in the frame. In still other embodiments, three contiguous intervals in the frame that are transmitted by the ATC to the radiotelephones are transmitted at lower power than the remaining intervals in the frame. In still other embodiments, the lower power intervals can be used with the first selected radiotelephones that are relatively close to the ATC and / or are experiencing relatively small signal block, and the remaining intervals are transmitted at higher power for the seconds selected from radiotelephones that are relatively far from ATC and / or are experiencing relatively high signal blockage.

Declared differently, according to some embodiments of the invention, only a portion of the TDMA framework is used.

For example, only the first four time slots (or the last four, or any contiguous four) of a full-rate GSM frame are used to support traffic. The remaining intervals are left unoccupied (empty). In these embodiments, capacity may be lost.

However, as previously described, for voice services, half-rate GSM and even a quarter-rate can be relied upon to gain back capacity, with some potential degradation in voice quality.

The ranges that are not used are preferably contiguous, such as ranges 0 to 3 or 4 to 7 (or 2 to 5, etc.). The use of non-contiguous intervals such as 0, 2, 4 and 6, for example, may be less desirable. Figure 11 illustrates four intervals (4-7) being used and four contiguous intervals (0-3) being empty in a GSM frame.

It has been found experimentally, in accordance with these embodiments of the invention, that GPS receivers can perform significantly better when the interval between clashes of interference is increased or maximized. Without being limited by any theory of operation, this effect may be due to the relationship between the repetition period of the GPS C / A code (1 ms) and the duration of the GSM salvo (about 0.577 ms). With a GSM frame occupation including alternating intervals, each GPS signal code period can experience at least one beat, while a GSM frame occupation including four to five contiguous intervals allows the GPS receiver to derive sufficient clear information, as well to rotate through error events.

According to other embodiments of the invention, the embodiments of Figures 8-10 can be combined with embodiments of Figure 11. Furthermore, according to other embodiments of the invention, if a carrier fj of Figures 9 or 10 is underused, for example Because of the relatively small footprint of the innermost region of the cell, it can be used to support additional traffic through the much larger outermost region of the cell.

So, for example, assume that only the first four 5 intervals in each frame are being used for inland traffic. In embodiments of Figures 8-10, these four intervals are taking relatively low power salts, for example on the order of 100 mW or less, and can therefore appear as unoccupied (almost) from an interference point of view. Loading the remaining four (contiguous) time slots with relatively high power clusters can have a negligible effect on a GPS receiver because the GPS receiver would continue to operate reliably based on the benign contiguous time slot occupied by the four low-power GSM clusters . Figure 12 illustrates embodiments of a frame on the carrier supporting four low power users (internal range) and four high power users (outer range). In reality, embodiments illustrated in Figure 12 may be a preferred strategy for the set of available carrier frequencies that are closest to the GPS band. These embodiments can prevent undue loss of capacity by loading carrier frequencies more completely.

The experimental finding that interference from patients with

GSM can be relatively benign for GPS receivers as long as no more than, for example, 5 intervals per 8-interval GSM frame are used contiguously, it can be very useful. It can be particularly useful since this experimental finding can be maintained even when the GSM carrier frequency is brought very close to the GPS band (as close as 1558.5 MHz) and the power level is set relatively high.

For example, with five contiguous time intervals per populated frame, the GPS receiver measured in the worst case can reach at least 30 dB of desensitization margin across the entire ATC service area, even when the ATC is radiating in 1558 , 5 MHz. With four contiguous time intervals per populated frame, an additional 10 dB desensitization margin can be earned for a total of 40 dB for the worst-case GPS receiver, even when the ATC is radiating at 1558.5 MHz.

There may still be concern about the potential loss in network capacity (especially in data mode) that can be incurred through the frequency range where the embodiments in Figure 11 are used to subpopulate the frame. In addition, while the embodiments of Figure 12 can prevent loss of capacity by fully loading the carrier, they can thus be subject to the constraint of filling the frame with both low power and high power users. In addition, if forward link carriers are limited to 5 contiguous high power intervals per frame, the maximum forward link data rate per carrier that can be achieved on a particular user may become less proportionately.

Therefore, in other embodiments, carriers that are subject to contiguous empty / low power intervals are not used for the forward link. Instead, they are used for the return link. Consequently, in some embodiments, at least part of the ATC is configured in inverse frequency mode compared to the SBC in order to allow maximum data rates over the routing link across the entire network. In the inverse frequency return connection, a radiotelephone can be limited to a maximum of 5 intervals per frame, which may be suitable for the return connection. If the five time slots available per frame, on a reverse frequency return link carrier, are assigned to one radiotelephone or to five different radiotelephones, they can be assigned contiguously in these embodiments. As described with respect to Figure 12, these five contiguous intervals can be assigned to high power users while the remaining three intervals can be used to serve low power users.

Other embodiments can be based on operating the ATC entirely in inverse frequency mode compared to the SBC. In these embodiments, an ATC transmits via the satellite return link frequencies while the radiotelephones respond through the satellite forward link frequencies. If sufficient contiguous spectrum exists to support CDMA technologies, and in particular the emerging 3G Broadband CDMA standard, the ATC routing link can be based on Broadband CDMA to increase or maximize data processing capabilities. GPS interference may not be an issue since ATCs transmit over the satellite return link in these embodiments. Instead, interference may become a concern for radiotelephones. Based, however, on embodiments of Figures 11-12, radiotelephones can be configured to transmit GSM since ATC return link rates are expected, in any case, to be lower than those of the forward link. Therefore, the ATC return link can employ GPRS-based data modes, possibly even EDGE. Thus, return link carriers that fall within a predetermined frequency range of the GPS band edge of 1559 MHz, can be underloaded, for embodiments of Figures 11 or 12, to satisfy GPS interference considerations.

Finally, other embodiments can use a partial or full inverse frequency mode and can use CDMA on both forward and return connections. In these embodiments, the ATC routing link for radiotelephones uses the frequencies of the satellite return link (1626.5 MHz to 1660.5 MHz), while the ATC resume link of the radiotelephones uses the frequencies of the routing link. satellite (1525 MHz to 1559 MHz). The ATC routing link can be based on an existing or developing CDMA technology (for example, IS-95, Broadband CDMA, etc.). The ATC network return link can also be based on an existing or under development CDMA technology as long as the radiotelephone output is activated to stop transmissions for approximately 3 ms once every T ms. In some embodiments, T will be greater than or equal to 6 ms.

This activation may not be needed for carriers of ATC return link at approximately 1550 MHz or below. This activation can reduce or minimize the effects of out-of-band interference (desensitization) for GPS receivers in the vicinity of an ATC. To increase the benefit for GPS, activation between all radiotelephones over an entire ATC service area can be synchronized substantially. Additional benefit for GPS can be derived from extensive activation system synchronization. ATCs can instruct all active radiotelephones for the time of activation. All ATCs can be synchronized by GPS.

Multi-Band / Multi-Mode Satellite Radiotelephone Communication Systems and Methods

Some embodiments of the present invention that have been described above can use the same satellite radio link band and satellite feeder link band for space-based communication with radio phones in all satellite cells of the satellite footprint or service area. In addition, some embodiments of the present invention that have been described above can use the same satellite radio frequency band and substantially the same air interface for terrestrial communication with radiotelephones using an auxiliary terrestrial network. Other embodiments of the present invention that will now be described can use more than one band and / or more than one air interface in several satellite cells in the satellite footprint or service area. In still other embodiments, although different bands and / or different air interfaces can be used in different satellite cells or within a satellite cell, the satellite radio frequency band and the air interface that is used for terrestrial communication between an auxiliary terrestrial network and radiotelephones within a given satellite cell, it is substantially the same as it is used for space-based communication with radiotelephones within the given satellite cell or in different satellite cells.

As used here, substantially the same band means that the bands substantially overlap, but that there may be some areas of non-overlap, for example at the ends of the band.

In addition, substantially the same air interface means that the air interfaces are similar, but need not be identical. Some changes can be made to the air interface to account for different characteristics for terrestrial and satellite environments. For example, a different vocoder rate can be used (for example, 13 kbps for GSM and 4 kbps for satellite), a different forward error correction encoding and / or a different interleaving depth can be used.

Multi-band / multi-mode satellite radiotelephone communication systems and methods according to some embodiments of the present invention can be used when a satellite footprint or service area crosses a geographical area in which two or more terrestrial radiotelephone systems (wireless network operators) are present, to add space-based communication capabilities to two or more terrestrial networks. Within a geographical area that is covered by a given terrestrial radiotelephone system, embodiments of the invention may provide additional capacity and / or extended services using the space-based component and / or the auxiliary terrestrial network, using substantially the same band and / or air interface like the terrestrial radiotelephone system. Thus, different geographic regions corresponding to different terrestrial radiotelephone communication systems and methods according to embodiments of the invention may use different bands and / or air interfaces for compatibility with terrestrial radiotelephone systems that are located within different geographic areas. There may also be other scenarios in which it may be desired for a single satellite radiotelephone communication system / method to employ different bands and / or air interfaces across the same and / or different geographic regions of it.

Figure 16 is a schematic diagram of satellite radiotelephone systems and methods according to some embodiments of the invention. As shown in Figure 16, these embodiments of satellite radiotelephone systems and methods include a 1610 space-based component, which is configured to communicate with 1620a20 1620c radioteles in a 1630 satellite footprint, which is divided into a plurality of cell satellite 1640a-1640c. It will be understood by those skilled in the art that, although three satellite cells 1640a-1640c and three radiotelephones 1620a-1620c are illustrated in Figure 16, satellite radiotelephone systems and methods according to embodiments of the present invention may employ more than three cells of satellite 1640a-1640c and can employ more than three radiotelephones 1620a-1620c.

Still referring to Figure 16, the space-based component 1610 is configured to communicate with a first radiotelephone 1620a between a first satellite cell 1640a through a first frequency band and / or a first air interface, and to communicate with a second radiotelephone 1620b in a second satellite cell 1640b through a second frequency band and / or a second air interface. In other embodiments, the first radiotelephone 1620a and the second radiotelephone 1620b can be in the same satellite cell.

Still referring to Figure 16, in some embodiments of the present invention, an auxiliary terrestrial network 1650 is configured to communicate over land with the first radiotelephone 1620a substantially through the first frequency band and / or substantially the first air interface, and to communicate overland with the second 1620b radiotelephone substantially through the second frequency band and / or substantially the second air interface. These substantially the same first frequency band and / or first interface in the first satellite cell 1640a and the portion of the auxiliary terrestrial network 1650 therein are illustrated by the vertical dashed lines covering the first satellite cell 1640a and the portion of the auxiliary terrestrial network 1650 in it. Substantially the same second frequency band and / or second air interface in satellite cell 1640b and the auxiliary terrestrial network portion 1650 therein, is illustrated by the horizontal dashed lines covering the second satellite cell 1640b and the terrestrial network portion assist 1650 in it.

It will be understood that in Figure 16, the auxiliary terrestrial network 1650 is illustrated as including a small number of auxiliary terrestrial network cells for simplicity.

However, more auxiliary terrestrial network cells may be present in some embodiments of the present invention. In addition, it will also be understood that, in some embodiments, a first portion of the auxiliary terrestrial network 1650 within the satellite cell 1640a can be operated by a first wireless network operator and a second portion of the auxiliary terrestrial network 1650 within the first cell of satellite 1640a or within the second satellite cell 1640b can be operated by a second wireless operator. Therefore, some embodiments of the invention provide systems and methods for adding space-based communication to the first and second terrestrial networks.

Referring again to Figure 16, satellite radiotelephone systems and methods according to some embodiments of the present invention also include a 1660 connection point, which is configured to communicate with the 1610 space-based component via a 1670 feeder connection The feeder link 1670 is configured to carry communication between the space-based component 1610 and the first and second radio telephones 1620a, 1620b. In some embodiments, the feeder connection 1670 includes the first air interface and the second air interface. Finally, it will also be understood that a third satellite cell 1640c, a third radiotelephone 1620c and substantially the same third frequency band and / or air interface is illustrated by dashed lines in the satellite cell 1640c. In other embodiments, the third radiotelephone 1620c is in the same cell as the first radiotelephone 1620a and / or the second radiotelephone 1620b.

Figure 17 is a schematic diagram of satellite radiotelephone systems and methods according to other embodiments of the present invention. As shown in Figure 17, a 1710 space-based component is configured to communicate with a first 1720a radiotelephone via a first frequency band and / or first air interface

1780a, also referred to in Figure 17 as Fl / Il.

As also shown in Figure 17, the space-based component 1710 is also configured to communicate with a second radiotelephone 1720b via a second frequency band and / or a second air interface 1780b, also referred to in Figure 17 as F2 / I2 .

An auxiliary terrestrial network 1750 is configured to communicate over land with the first radiotelephone 1720a substantially through the first frequency band and / or substantially through the first air interface 1790a, also designated in Figure 17 as F1 '/ I1', and for communicate overland with the second 1720b radiotelephone substantially through the second frequency band and / or substantially the second 1790b air interface, also designated in Figure 17 as F27I2 '. The auxiliary terrestrial network 1750 can be included within a single satellite cell or can be spread across multiple satellite cells.

As also shown in Figure 17, the auxiliary terrestrial network can include a first auxiliary terrestrial component 1752a, which is configured to communicate by land with the first radiotelephone 1720a substantially through the first frequency band and / or substantially the first air interface. 1790a. A second auxiliary terrestrial component 1752b is configured to communicate overland with the second radiotelephone 1720b substantially through the second frequency band and / or substantially the second air interface 1790b. As was the case in Figure 16, a large number of 1720 radiotelephones and / or auxiliary terrestrial components 1752 can be provided in some embodiments. The first and second auxiliary terrestrial components 1752a 1752b, respectively, can be part of two separate wireless networks in the same and / or different satellite cells, in some embodiments. Thus, some embodiments of Figure 17 provide systems and methods for adding space-based communication to the first and second terrestrial networks. A connection point 1760 and a feeder connection 1770 can be provided, as described with reference to Figure 16.

Some embodiments of the present invention provide satellite radiotelephone systems and / or methods that include radiotelephone connections that are operative over a plurality of bands. In some embodiments, the band-sensitive (ie, frequency-sensitive) components of the 1610, 1710 space-based component, such as the antenna power network, power amplifiers, low noise amplifiers, etc., can be designed to be broadband, so that the operating range of the space-based component can extend across a plurality of service link bands, such as L band, S band, etc. In other embodiments, separate components for each band can be provided. In still other embodiments, some common broadband components and some separate narrowband components can be provided.

In addition, other embodiments of the present invention can provide multi-mode payload capability, providing a plurality of air interfaces that can be used to provide radiotelephone communication with the 1610, 1710 space-based component and a plurality of radiotelephones 1620, 1720 in a satellite footprint through it and / or a plurality of satellite cells. The space-based component 1610, 1710 can be configured to support a plurality of air interface standards, for example having a programmable channel increment that can be responsive to ground commands. Different channel increments, for example, can be applied by the space-based components 1620, 1720 to different bands of the received feeder connection signal 1670, 1770 from a connection point 1660, 1760. These different bands of the feeder connection spectrum may remain constant or may change over time, depending on the traffic carried by each air interface pattern that can be supported by the satellite radiotelephone system.

Thus, in some embodiments, the feeder connection 1670, 1770 can be segmented into bands, such as B bands_B B₂ and B₃. In one example, Bi band can carry GSM carriers between the connection point and the space-based component, band B₂ can carry narrow band and B band CDMA carriers₃ can carry broadband CDMA carriers. It will be understood by those skilled in the art that corresponding return feeder connection bands can be provided for carriers of the space-based component 1610, 1710 to the connection point 1660, 1760. In other embodiments of the present invention, an auxiliary terrestrial network 1650 , 1750 can also be provided to communicate over land with 1620, 1720 radiotelephones in the satellite footprint. Thus, in some embodiments, the auxiliary terrestrial network 1650, 1750 may provide a larger portion of the radiotelephone communication in urban areas, while the space-based component 1610, 1710 may provide a larger portion of the radiotelephone communication in rural areas.

Figure 13 is a block diagram of satellite radiotelephone systems and / or methods that can use multiple bands and / or multiple modes according to some embodiments of the present invention. It will be understood by those skilled in the art that Figure 13 relates to GSM, and system elements that provide a GSM air interface are shown. However, other satellite radiotelephone systems and / or methods can also be provided according to embodiments of the present invention.

In particular, as shown in Figure 13, these embodiments of satellite radiotelephone communication systems and methods include a 1310 space-based component, for example a geostationary satellite, and at least one 1360 Connection Point Station System (GSS) , Network Operation Center (NOC) 1362, Mobile Switching Center (MSC) 1364, Base Station Controller (BSC) 1366 and Base Transceiver Station (BTS) 1368. The satellite radiotelephone system can be connected to the Public Switched Telephone Network (PSTN)

1772 and / or one or more 1774 Public Data Networks (PDN). In addition, to offer a General Packet Radio Service (GPRS), some 1364 MSCs can be augmented by appropriate packet switching facilities, generally referred to as Node Support GPRS Service (SGSN) and GPRS Connection Point Support Node (GGSN). The GSS Rastreamento (TT &amp; C) 1776. A plurality can also be connected to a Telemetry and Command system of radiotelephones 1320 can also be provided.

Figure 14 illustrates the frequency reuse between a space-based component and an auxiliary terrestrial network according to some embodiments of the present invention. As shown in Figure 14, relatively small auxiliary terrestrial network cells 1450 are nested within the relatively large satellite cells 1440. This may be because, even with large reflectors that can be used in the space-based component 1410, satellite cells 1440 can still be in the order of several hundred kilometers in diameter, while auxiliary terrestrial network cells can be two , three or more orders of magnitude smaller than satellite cells. In Figure 14, the terrestrial reuse of the same carrier frequency is indicated by the same symbol (□ or *).

Embodiments of the present invention as shown in Figures 13 and 14 may allow a single satellite radiotelephone system to support a plurality of auxiliary terrestrial components 1452 on an auxiliary terrestrial network 1450, with at least some of the auxiliary terrestrial components 1452 providing terrestrial connectivity over one different air interface. This may allow the relatively large 1430 satellite footprint to be used in a terrestrial market that is segmented. Thus, in some embodiments, the satellite radiotelephone system can be configured to support an auxiliary ground component based on

GSM, an auxiliary terrestrial component based on narrowband CDMA, and an auxiliary terrestrial component based on broadband CDMA, at the same time and through the same or different satellite cells. In other embodiments, a subset of auxiliary ground components may be operating in the L band, for example, while another subset of auxiliary ground components may be operating in the S band.

As already described, in some embodiments, satellite radiotelephone communication systems and methods can provide substantially the same band / same air interface service for both space-based communications with the space-based component and terrestrial communications with at least one of its auxiliary ground components. This can allow simplified radiotelephones.

In particular, Figure 15 is a block diagram of radiotelephones 1520 that can be used to communicate with a space-based component and an auxiliary terrestrial component in satellite radiotelephone systems or methods according to some embodiments of the present invention. In some embodiments, these 1520 radiotelephones can be used with satellite radiotelephone systems according to some embodiments of the present invention that include an auxiliary ground component and a space-based component that use substantially the same band and substantially the same air interface. The ability to reuse the same spectrum for space-based and terrestrial communication can facilitate low-cost, small and / or light weight radiotelephones, according to some embodiments of the present invention.

In addition, some embodiments of the present invention may put more of the burden of bonding performance with the space-based component in place of the radiotelephone, compared to earlier satellite radiotelephone systems, such as Iridium or Globalstar.

Therefore, large antennas may not need to be used on the radiotelephone. Instead, antennas that are similar to conventional cellular radiotelephone antennas can be used.

Therefore, referring to Figure 15, a single 5-frequency chain (RF) including low pass filters 1522, top and bottom converters 1524a, 1524b, Local Oscillators (LO) 1526, Low Noise Amplifier (LNA) 1528 , Power Amplifier (PA) 1532, passband filters 1534 and antenna 1536, can be used. A single 1542 baseband processor can be used, including an analog to digital (A / D) converter 1544, a digital to analog converter (D / A) 1546 and a 1548 Human Machine Interface (MMI). One interface of optional Bluetooth 1552 can be provided. An Application Specific Integrated Circuit (ASIC) 1554 may include Random Access Memory (RAM) 1556, Read-Only Memory (ROM) 1558, a microprocessor (μΡ) 1562, logic for auxiliary terrestrial communication (ATC Logic) 1564 and logic for space-based communication (Space Segment Logic or SS Logic) 1566. SS 1566 Logic can be used to accommodate single satellite requirements across and above those of cellular or PCS, such as a single satellite vocoder, a satellite forward error correction coding scheme, a single satellite interleaver, etc. However, this added port bill may not increase the cost of the ASIC 1554.

According to other embodiments of the invention, the space-based component can be sized appropriately, so that there is no need for radiotelephones to use large 1536 antennas or to have to radiate any more power when in satellite mode than when in terrestrial mode. An appropriate level of connection strength can be achieved by the spot beam gain that can be provided by a larger satellite antenna and / or other techniques. This can more than compensate for the several dB reduction in satellite link strength that can occur when removing a large satellite antenna from the radiotelephone and / or using a single antenna for terrestrial and satellite communication. Therefore, single mode and single band radiotelephones can be provided that can communicate with the space-based component and the auxiliary terrestrial network • 5 through a single band and single air interface.

Control of Aggregate Radiated Power for Multi-Band / Multi-Mode Satellite Radiotelephone Communication Systems and Methods

Multi-band / multi-mode satellite radiotelephone communication systems and methods according to other embodiments of the present invention will now be described.

In particular, referring to Figure 18, a satellite radiotelephone system includes a space-based component 1610 that is configured to communicate with a plurality of radiotelephones through a plurality of frequency bands and / or a plurality of air interfaces. . The connections using the plurality of frequency bands and / or air interfaces are denoted in Figure 18 as 1880a-1880f, although it will be understood that more or less frequency bands / air interfaces can be used. An auxiliary terrestrial network (ATN) 1850 is configured to communicate over land with the plurality of radiotelephones substantially through the plurality of frequency bands and / or substantially the plurality of air interfaces. It will be understood that, in Figure 18, five auxiliary terrestrial components (ATC) 1852a-1852f are shown, although more or less auxiliary terrestrial components can be used in the auxiliary terrestrial network 1850. A satellite connection point 1660 and a PDN / PSTN 1810 they are also provided as already described.

Still referring to Figure 18, an aggregated radiated power controller 1820 is provided, which is configured to limit an aggregated radiated power by the plurality of radiotelephones to a maximum aggregated radiated power. In some embodiments, the aggregated radiated power controller is configured to control a plurality of co-frequency radiotelephones, thus to limit the aggregated radiated power by the plurality of co-frequency radiotelephones to a maximum aggregated radiated power. As used here, co-frequency means that radiotelephones use the same carrier frequency even if they use different TDMA time slots (different TDMA channels) or use different CDMA spread codes (different CDMA channels). Therefore, compliance with irradiation requirements for the auxiliary terrestrial network 1850 can be maintained although the auxiliary terrestrial network 1850 employs a plurality of frequency bands and / or air interfaces. It will be understood that the 1820 aggregate radiated power controller can be provided as an independent component, as part of the connection point 1660, and / or as part of another component of the satellite radiotelephone and / or ATN system.

In some embodiments of the present invention, the 1820 aggregate radiated power controller is configured to allow control substantially across the entire ATN and / or substantially all of the radiotelephones that across the entire ATN and / or substantially all radiotelephones that are communicating with he. However, in other embodiments of the present invention, the aggregated radiated power controller 1820 is configured to limit an aggregated radiated power over a subset of the plurality of radiotelephones to a maximum aggregated radiated power. For example, in some embodiments, the plurality of frequency bands includes a first frequency band and a second frequency band, and the subset of the plurality of radiotelephones includes radiotelephones that communicate over land with the auxiliary terrestrial network substantially through the first frequency band. In some embodiments, the first frequency band includes L-band frequencies, and in some embodiments, the second frequency band includes S-band frequencies. In other embodiments, the first frequency band includes L-band frequencies that are used substantially between horizon-radio by another system and the second frequency band includes L-band frequencies that are not used substantially between radio-horizons by another system. In these embodiments, the second frequency band may additionally include frequencies of the S band.

Thus, in some embodiments, only a first subset of ATN, and / or radiotelephones communicating with it, may be subject to control of aggregate radiated power, while a second subset of ATN, and / or the radiotelephones that are communicating with it need not be subject to control of aggregate radiated power. For example, L-band frequencies that are radiated overland can potentially cause interference with another system, and may be subject to control of aggregate radiated power. In contrast, S-band frequencies and L-band frequencies that are not used substantially between radiohorizons by another system may not potentially cause interference with another system, and therefore may not be subject to control of aggregate radiated power, in accordance with embodiments of this invention.

More specifically, a Mobile Satellite System (MSS) including an ATN 1850 can provide voice and / or data services to end users through its footprint using more than one air interface protocol. It may be desirable for the system to be able to provide services to end users over various air interface protocols given the current fragmentation and potential future uncertainty in the US radio telephone communication market. Currently, the US market can be served by iDEN, GSM and cdma2000, but other emerging standards, such as WCDMA and / or OFDM / OFDMA, may be used in the future. A system architecture that lends itself to the plurality of current standards (air interface protocols) and can also accommodate future technologies (currently anticipated or not) can offer increased flexibility.

Figure 18 illustrates a potential development scenario for ATN. As shown, different and / or overlapping geographic areas, 5 can be served by ATCs 1852a-1852f, ​​which are using different air interface protocols. Satellite 1610 is capable of transporting the plurality of protocols to / from satellite connection point 1660, where different sets of transceiver units can be associated with the processing of different air interface waveforms. The radiotelephone may contain an integrated transceiver capable of communicating via the 1610 satellite or at least an ATC 1852, and potentially via another PCS / cellular band, depending, for example, on business relationships that can be established with other wireless operators. The satellite / ATN portion of the radiotelephone transceiver can use substantially the same air interface protocol to communicate via satellite 1610 or at least an ATC 1852. This approach can reduce or minimize the size, weight and / or cost of manufacturing the transceiver by increasing the level of hardware and software integration and reuse for both satellite and ATN modes.

In some embodiments of the invention, ATN can be based on a CDMA air interface protocol without producing any potential interference greater than the rules of the Federal Communication Commission allow for a GSM-based ATN. See, Report and Order and Proposed Rulemaking News, FCC 03-15, Flexibility for Delivery of Communications by Mobile Satellite Service Providers in the 2 GHz Band, the L-Band, and the 1.6 / 2.4 Bands, IB Record No. 01-185, Adopted: January 29, 2003, Released: February 10, 2003, hereinafter referred to as FCC 03-15. Thus, the technology used by ATN or any of its ATCs may be irrelevant as long as the level of aggregated co-frequency emissions is controlled so as not to exceed the limit published by the Commission for the specific GSM system considered in FCC 03-15. As such, an ATN 1850 can be developed to work with a plurality of air interface protocols simultaneously, as long as it adheres to the spectral density limit of aggregated radiated power published by the Commission (ie, -53 + 10log (1,725) dBW / Hz).

In FCC 03-15, the terrestrial reuse of 1,725 ​​allowed by the Commission, by ATN in the USA, of a GSM carrier that is also used by the MSS for satellite communication. A single GSM carrier fully charged on an ATC return link, which is being beamed from several radiotelephones (up to eight) to a base station, can launch a maximum of -53 dBW / Hz of spectral power density into space. The spectral density of maximum aggregate power that can be launched in the space of 1,725 ​​fully loaded co-channel GSM carriers is therefore -53 + 10log (1,725) «-20.64 dBW / Hz. This is based on a GSM radiotelephone peak EIRP of 0 dBW, consistent with FCC 03-15 analysis. It is this spectral density of maximum aggregate power, produced at the return link by ATN's maximum allowed wide frequency reuse in the USA, that the Commission has concluded that it can potentially raise the noise background of Inmarsat satellite receivers by up to 0.7% .

The maximum EIRP of a CDMA return connection code (user) can be -10 dBW and can be transmitted through a carrier occupying a bandwidth of 1.25 MHz in accordance, for example, with the interface standard of air from cdma2000. Thus, -10-10log (1,250,000) «-70.97 dBW / Hz of spectral power density can be launched into space by a single CDMA (user) code operating on an ATC return link. The maximum aggregate power spectral density limit -20.64 dBW / Hz allowed, as derived above, can therefore accommodate approximately 1O^[(70,97^{2θ, 64) / 1θ}] «107,894 co-channel return link CDMA codes. This result can be used to establish an equivalence relationship, for the ATN return link, between a pure GSM ATN and a pure CDMA ATN.

Thus, from the point of view of aggregate return interference power spectral density, reuse of broad frequency in the USA of 1,725 ​​of a GSM carrier by ATN can be considered equivalent to approximately 107,894 codes (users) transmitting broadly in USA on a given 1.25 MHz CDMA carrier. The number of users is generally less than or equal to the number of codes, because a user can be allocated to more than one code to improve the reliability and / or rate of transmission data. The declared equivalence is based on the peak return link EIRP of the GSM assumed to be 0 dBW, whereas a CDMA code is assumed to be -10 dBW.

A mathematical equivalence can be established between a single time interval of GSM (transmitting) active (user) transmitting to a peak EIRP of 0 dBW, and several CDMA codes (users) being active and each transmitting to a peak EIRP -10 dBW. This relationship can allow the development of an ATN that contains both GSM and CDMA technologies, and potentially fluctuating capacity between the two, and is, from the point of view of aggregate return interference power spectral density potential, equivalent to the pure GSM system that the Commission dealt with in FCC 03-15.

In particular, according to FCC 03-15, there are 1,725 ​​x 8 = 13,800 GSM time slots (users) that can be active on ATN (wide USA) on a given GSM carrier, while maintaining the potential for increased noise for Inmarsat satellite receivers at 0.7%. It has been shown above that, from the point of view of interference potential of aggregate upper link power spectral density, this is equivalent to approximately 107,894 codes (users) transmitting on a given 1.25 MHz CDMA carrier (USA wide) . Thus, an active co-frequency GSM range (user) equals approximately 107.894 / 13,800 «7.8184 active safe frequency CDMA codes (users). Thus, an equation that can be used to govern co-frequency ATN operations across the United States can be:

Ngsm + 13,800N_CDma / 107,894 = 13,800 (1)

In Equation (1), N_GSm denotes the number of active co-frequency GSM time slots (users), while Ncdma denotes the number of active co-frequency CDMA codes (users). In some embodiments, the GSM time slots of N_Gsm are at least partially co-frequency with CDMA codes of N_Çdma- Since there are 6 distinct GSM carriers that can be co-frequency with a single 1.25 MHz bandwidth CDMA carrier, the co-frequency CDMA carrier load will be emptied by the same amount of 13,800N_CDma / 107,894, the wide USA capacity of all 6 corresponding GSM carriers (co-frequency with the CDMA carrier). Based on the above, it is seen that a large US ATN network that is configured to simultaneously support both GSM and cdma2000 traffic can be compliant with the Commission's upper link interference constraint (no more than 0.7% ΔΤ / Τ impact, for example, for Inmarsat) if and only if Equation (1) is substantially satisfied. The MSS / ATN operator may agree to divide the total co-frequency traffic into such an ATN substantially in accordance with Equation (1).

As discussed earlier, a fully charged GSM return link carrier (all eight time slots occupied) can generate -53 dBW / Hz of maximum EIRP density potential. This result is based on radiotelephones / GSM radio terminals having an antenna gain of, for example, 0 dBi and radiating a maximum 0 dBW EIRP across a 200 kHz carrier bandwidth (according to the assumptions of FCC in FCC 03-15).

A cdma2000 ATN radio terminal having, for example, an antenna gain of 0 dBi can be limited (by design) to a maximum of, for example, EIRP of -9 dBW while communicating using a single code. Given the 1.25 MHz carrier bandwidth of cdma2000 (lxRTT), the maximum EIRP density that can be generated by a single cdma2000 return link code can be -9 - 10log (1.25 x 10⁶) «-70 dBW / Hz. So it follows that 10^[(7° ^53)/10·¹ «50 co-frequency cdma2000 codes can generate the same spectral density potential of superior link interference power as a fully charged GSM carrier.

For W-CDMA, an ATN radio terminal having, for example, an antenna gain of 0 dBi can be limited (by design) to a maximum of, for example, EIRP of -9 dBW, while communicating using a single code. Given the 5 MHz carrier bandwidth of W-CDMA, such a radio terminal can generate an EIRP density potential of -9-10log (5 x 10⁶) '-76 dBW / Hz. So 10^[(76’^53)/10] «200 co-frequency W-CDMA codes can generate the same spectral density potential of superior link interference power as a fully charged GSM carrier.

For an ATN that can be based on all three technologies (GSM, cdma2000 and W-CDMA), the following constraint equation can be used to specify the allowed distribution of co-frequency air traffic associated with the three standards:

N / 8 + M / 50 + L / 200 = R (2), where N denotes the number of GSM time slots (channels) supported by wide ATN co-frequency by a given GSM carrier as that carrier is used and reused, M represents the number of cdma2000 co-frequency codes (channels) supported by a single cdma2000 carrier as that carrier is used and reused throughout the ATN, L identifies the number of W-CDMA co-frequency codes (channels) on a single W-CDMA carrier as that carrier is used and reused by ATN, and R denotes the ATN frequency reuse based on pure GSM authorized by the FCC.

In some embodiments, the N GSM time slots, the M cdma2000 codes and the L W-CDMA codes are at least partially co-frequency. Note that the above equation can provide a constraint that can be imposed on operational safe-frequency carriers (all three types of carrier, GSM, cdma2000 and W-CDMA whose broad ATN traffic is divided according to the previous equation can be co- operating frequency). In addition, for an ATN development based on pure GSM, the previous equation reduces to N = 8R (M = L = 0), which confirms that the total number of time intervals (channels) that can be supported by an ATN broad range of single GSM carrier equals eight times the reuse of authorized frequency.

Since there are 6 GSM carriers that can fit within the bandwidth occupied by a single cdma2000 carrier, the global load (M) of a cdma2000 carrier can empty, by the same amount of M / 50, the global capacity of all 6 corresponding GSM carriers (co-frequency with cdma2000 carrier). Similarly, since there are 25 GSM carriers that can exist within the bandwidth occupied by a single W-CDMA carrier, the global load (L) of a W-CDMA carrier can be depleted by the same amount of L / 200 , the global capacity of all 25 carriers of

Corresponding GSM (co-frequency with the W-CDMA carrier). For similar reasons, since there are 4 cdma2000 carriers that can be accommodated (co-frequency) across the frequency band occupied by a W-CDMA carrier, the global load of a WCDMA carrier can be depleted by the same amount of L / 4, the global capacity of all 4 corresponding cdma2000 carriers (co-frequency with the W-CDMA carrier).

Equations (1) and (2) can be generalized as follows:

X

S Ni / Fi = MARP (3), where N, is the number of active co-frequency users using a given frequency band and / or air interface i;

Fi is a corresponding equivalence factor (which can be less than, greater than or equal to 1) for the given frequency band / air interface i; and

MARP is a measure of the maximum aggregated radiated power spectral density that is allowed.

It will be understood that in FCC 03-15, the Spectral Density of Irradiated Aggregate Power (PSD) that can be launched in the USA wide by radio terminals communicating with an ATN cannot exceed -53 + 10 log (1,725) «-20, 6 dBW / Hz. In reaching this conclusion, the FCC assumed that ATN will be based on GSM technology and that GSM radio terminals will be able to launch towards a safe frequency satellite system (eg Inmarsat) a maximum EIRP (upper link) ) of 0 dBW per carrier. The FCC's conclusion is also based on the assumption that only 50% of ATN is within the United States.

The broad US radiated aggregate PSD may be higher if more than 50% of the ATN is allowed to be within the U.S. For example, based on the development of 80% of the total ATN within the US, the aggregate broad US allowed PSD can grow to -53 + 10log (2,760) «-18.6 dBW / Hz. In FCC 03-15, the Commission concluded that the aggregate average signal attenuation that is relevant to the upper link interference is 242.7 dB. This number takes into account the attenuation / suppression of the interference signals due to (a) propagation of free space (188.7 dB), (b) satellite antenna discrimination of co-frequency system in the direction of the ATN (25 dB ), (c) outdoor blocking (3.1 dB), (d) closed-loop power control implemented by ATN (20 dB), (e) using a lower rate vocoder (3.5 dB) , (f) voice activity (1 10 dB), and (g) polarization discrimination provided by the coffequency satellite system (1.4 dB). (See FCC 03-15, Appendix C2, Table 2.1.1. C, page 206). Suppression of interference signal due to power control (20 dB) includes 2 dB due to narrowing range and 18 dB due to structural attenuation. Based on the Commission's conclusions / assumptions, as specified in FCC 03-15, and assuming the development of up to 80% of the ATN within the USA, the aggregate average PSD potential at the entrance to a co-frequency satellite antenna may be limited a -18.6 - 242.7 = -261.3 dBW / Hz.

As described above, aggregate radiated power control systems and methods according to some embodiments of the present invention, can be configured to limit an aggregated radiated power by a plurality of radiotelephones to maximum aggregate radiated power. In embodiments that were described above, it was assumed that ATN has the same amount of structural attenuation margin and / or return link margin for all auxiliary terrestrial components, which use a given frequency band and / or carrier frequency and / or air interface. The calculations that were described above were made under this assumption. However, this may not always be the case. Instead, according to other embodiments of the present invention, several ATCs in the ATN can provide different structural attenuation and / or return boundary margins. In fact, according to other embodiments of the present invention, the connection margins can be increased on several ATCs, to allow larger numbers of radio terminals to communicate over land without exceeding a maximum aggregate radiated power. Two illustrative examples will be provided. In a first example, a plurality of cdma2000 radio terminals communicate with the ATN infrastructure that provides 18 dB of structural attenuation margin. In a second example, not all ATN infrastructure provides 18 dB of structural attenuation margin.

Thus, in the first example, all cdma2000 ATC radio terminals communicate with the infrastructure that provides 18 dB of structural attenuation margin. For a satellite, a cdma2000 ATN radio terminal can radiate, for example, a maximum EIRP (spatially averaged) of -13 dBW per communication channel (ie by code; the EIRP consumed by the pilot channel is neglected because of simplicity). Consequently, the PSD potential of the radio terminal, per communication channel, can be -74 dBW / Hz (at the antenna output of the radio terminal) and -74 - 242.7 = -316.7 dBW / Hz at the antenna input. of the satellite. The number of such radio terminals (communication channels) that operate co-frequency in order to generate the allowed PSD potential of -261.3 dBW / Hz, at the entrance of a satellite antenna, is 10^{C (316.7}'^261,3)/10] = 346,736. In some embodiments, up to seven (7) carriers of cdma2000 can be developed at ATN. Thus, the total air capacity of a US-based ATN can be 346,736 x 7 = 2,427,152 simultaneous communication channels.

In the second example, not all radio terminals are communicating with the infrastructure that provides 18 dB of structural attenuation margin. For example, let X, Y and Z denote potential percentages (%) of the broad US of ATN cdma2000 radio terminals that may be communicating co-frequently with the ATN infrastructure that is providing A, B and C dB, respectively, of structural attenuation margin. Like this:

X + Y + Z = 100 (4)

Letting L, M and N denote the number of potential radio terminals that may be communicating with class A, B and C infrastructure, respectively, we can write:

X = 100L / (L + Μ + N), Y = 100M / (L + M + N), Z = 100N / (L + Μ + N). (5) Subject to the three ATN infrastructure classes / categories (as defined above) that may be serving the ATN radio terminals, the aggregate power spectral density potential (in Watts / Hz) at an antenna input satellite can be:

psd = [Εξ + Μζ + Νς] σ² Watts / Hz (6)

In Equation (6), the amount 101og (c²) can, for example, be specified as -74 dBW / Hz, and ξ, ζ, and ς can denote average aggregate attenuation factors (power domain) associated with the three classes of radio terminals that can be served by the three classes infrastructure, respectively. So, we can write:

lOlogfé) = - (188.7 + 25 + 3.1 + (A + 2) + 3.5 + 1 + 1.4) = - (224.7 + A) dB (7) 101og (Ç) = - (188.7 + 25 + 3.1 + (B + 2) + 3.5 + 1 + 1.4) = - (224.7 + B) dB (8) and 101og (ç) = - (188, 7 + 25 + 3.1 + (C + 2) + 3.5 + 1 + 1.4) = - (224.7 + C) dB (9)

Using Equation (5):

N = L [(100-X) (100-Y) -XY] / 100X, and M = 100YL / [(100-Y) (100-Z) - YZ] (10)

Substituting Equations (7) to (10) in Equation (6) and taking the logarithm, the average PSD potential in a victim satellite can be expressed as:

PSD = 101og (psd) = 101og (a²) + 101og (L) + 101og (10 '^{(22,47 +} °’^1A) + 10-(²²’^{47 +} °’^1B) x 100Y / [(100-Y) (100-Z) - YZ] + io⁽²²’^{47 + o&gt; 1C)} χ [(100-X) (100-Y) - XY] / 100X) (11) or,

-261.3 = -74 + 101og (L) + 101og (10-⁽²²’^{47 +} °’^1A) + ιο-⁽²²’^{47 + θ}’^1θ) χ 100Y / [(100-Y) (100-Z) - YZ] + ίο - (²²&gt;^{47 + 0}’^lc) x [(100-Χ) (100-Υ) - ΧΥ] / 100Χ) (12)

Solving for L:

L = 10 -18.73 -logO (13)

In Equation 13, the second term of the logO exponent is defined by Equation (12). I mean:

logO = log (10 '^{(22.47 + 0.1A)} + ιο-⁽²²’^{47 + θ}’^1Β) χ 100Y / [(100-Y) (100-Z) - YZ] + io (²²&gt;^{47 + ()}&gt;^lc) χ [(100-X) (100-Y) - XY] / 100X) (14)

Once L is found from Equation (13), N and M can be evaluated using Equations (5) as follows:

N = L [(100-X) (100-Y) -XY] / 100X, and M = Y (L + N) / (100-Y) (15)

The following table provides illustrative numerical results:

Table

<td>(%) / A (dB)</td><td>Y (%) / B (dB)</td><td>Z (%) / C (dB)</td><td>L</td><td>M</td><td>N</td><td>L + M + N</td><td>(L + M + N) x7</td>

<td> 100/18</td><td> 0/18</td><td> 0/18</td><td> 346,736</td><td> 0</td><td> 0</td><td> 346,736</td><td> 2,427,152</td>

<td> 60/22</td><td> 30/12</td><td> 10/6</td><td> 68,859</td><td> 34,439</td><td> 11,499</td><td> 114,797</td><td> 803,579</td>

<td> 30/18</td><td> 60/12</td><td> 10/6</td><td> 24,349</td><td> 48,685</td><td> 8,108</td><td> 81,142</td><td> 567,994</td>

Therefore, the second example that was described above can provide additional embodiments of Equation (3), where Nj denotes several co-frequency channels that are operative subject to a common structural attenuation margin (i-th) for a given band frequency and / or carrier frequency and / or air interface, F_; denotes a corresponding equivalence factor, which may be less than, greater than or equal to 1, for the common structural attenuation margin (i-th) for the given frequency band / carrier frequency / air interface, and MARP is a measure of the maximum aggregate radiated power, that is, the maximum aggregated radiated power spectral density (PSD).

In some embodiments of the invention, an ATN can be configured to maintain a list of infrastructure components (that is, base stations and / or base station groupings), and to associate with each infrastructure component a measure of Margin of Infrastructure. Structural Attenuation (SAM). Based on the procedure for registering radio terminals, and / or other means, ATN can also be configured to be aware of the infrastructure component with which each active radio terminal (in the air) is communicating. Thus, the ATN can be configured to associate a SAM with each active radio terminal and can thus be configured to evaluate the quantity Ei (psd) i, where psd denotes a spectral power density on a satellite and where the addition can be performed through a set of active radio terminals (in the air) that are operating in co-frequency at ATN (ie, they are sharing in whole or in part a band of ATN and / or sub-band of frequencies). In some embodiments of the invention, the quantity (psd) i can be evaluated for the i-th co-frequency radio terminal as:

(psd) i = 10^{[log (pi / Bwi) + log (ai)]} (16), where the amount 10logfo) can denote a measure of the maximum EIRP in the direction of a satellite that can be generated by the i th active radio terminal (in the air) (for example, -4 dBW for GSM, -13 dBW for cdma2000e / or W-CDMA), BWj can denote a measure of the bandwidth occupied by the carrier being radiated by the i-th active radio terminal (for example, 200 kHz for GSM, 1.25 MHz for cdma2000 and 5 MHz for W-CDMA), and 10log (ctj) can denote an aggregate signal attenuation measure that may exist between the i-th radio terminal and a satellite.

The amount 10log (ctj) can additionally be expressed as 10log (cti) = - (L + SAMj) dB, where L is defined as a measure of aggregate signal attenuation potential including, for example, (a) free space propagation (ie 188.7 dB), (b) co-frequency satellite antenna discrimination (ie, 25 dB), (c) outdoor blocking (ie, 3.1 dB), (d) control of ATN power due to narrowing range (ie, 2 dB), (e) low rate vocoder effect (ie, 3.5 dB), (f) effect of voice activity (ie, 1 dB), and (g) polarization discrimination provided by a co-frequency satellite antenna (ie, 1.4 dB). (See FCC 03-15, Appendix C2, Table 2.1.1.C; page 206). SAM, can denote a measure of structural attenuation margin provided by the infrastructure component (ie, a base station and / or a group of base stations) with which the ith active co-frequency radio terminal is communicating . Typical values ​​for SAMj can be, for example, 22 dB, 18 dB, 12 dB and 6 dB, for dense urban, urban, suburban, and rural infrastructure components, respectively.

Accordingly, in some embodiments of the present invention, the aggregated radiated power controller is configured to control a plurality of co-frequency radio terminals, thus to limit the aggregated radiated power by the plurality of radio terminals to a maximum aggregated radiated power. according:

X

S (psd) i = MARP (17) where (psd) i is a measure of the spectral density of power radiated on a satellite and MARP is a measure of maximum allowed aggregate radiated power. In some embodiments, psd is determined according to (psd) i = io^[1°^{s (pi / BWl) + 1}°^leaves)], where 101og (pi) denotes a measure of maximum radiated power by the i-th radio terminal in one direction of a satellite, BWj denotes a bandwidth occupied by a carrier that is radiated by the i-th radio terminal and 10log (oti) denotes a measure of signal attenuation (in dB) between the i-th radio terminal and the satellite.

ATN can evaluate the amount Ei (psd) i, and / or another measure of it, as needed, and can, in response to the value of Ei (psd) i, and / or the value of the other measure, approaching, being equal a, or having exceeded a threshold value, control the auxiliary terrestrial network and / or one or more of the radio terminals to limit the aggregate radiated power to a maximum aggregate radiated power.

Many techniques can be used to limit the aggregate radiated power. For example, in some embodiments, one or more co-frequency radio terminals can be commanded to 1) use a lower rate vocoder, and / or 2) reduce the transmission rate, and / or 3) use other available ATN or non-ATN resources that may not be co-frequency with those resources that are relevant to the Ej amount (psd) (ie, a frequency that did not exceed the maximum aggregate radiated power) and / or another measure thereof. Thus, in some embodiments, the aggregated radiated power controller is configured to control the plurality of radio terminals by reducing a vocoder rate of at least one of the radio terminals, and / or reducing an information transmission rate of at least one the radio terminals, and / or controlling at least one of the radio terminals to communicate using a frequency that does not exceed the maximum aggregate radiated power, thus to limit an aggregated radiated power by the plurality of co-frequency radiotelephones to the maximum aggregated radiated power.

Many different techniques can also be used to determine which radio terminal and / or which portion of the auxiliary terrestrial network to control to reduce the aggregate radiated power, according to various embodiments of the present invention. Thus, in some embodiments, at least one radio terminal is selected and controlled as described above, in order to reduce the aggregate radiated power. In other embodiments, at least one radio terminal which is subject to a low structural attenuation margin, and in some embodiments a lower one, and which is therefore radiating at a relatively high level, can be controlled according to any of the embodiments described above.

In addition, in other embodiments, a radio terminal can be selected based on the frequency band and / or carrier frequency and / or air interface it is using, so that if a given frequency band and / or carrier frequency and / or air interface exceeds a desired maximum aggregate radiated power, one or more radio terminals that are using that frequency band and / or carrier frequency and / or air interface can be controlled. Therefore, in some embodiments, the aggregated radiated power controller is configured to control a plurality of radio terminals, controlling at least one radio terminal that is communicating with ATN over a frequency band and / or carrier frequency and / or air interface that has exceeded a maximum aggregate radiated power for that frequency band and / or carrier frequency and / or air interface, thus to limit the aggregate radiated power by the plurality of radio terminals for the frequency band and / or carrier frequency and / or air interface to a maximum aggregate radiated power for the frequency band and / or carrier frequency and / or interface air. A priori, quotas of radiated power for a given frequency band and / or carrier frequency and / or air interface can be observed by this means.

In yet other embodiments of the invention, the aggregated radiated power controller is configured to control the auxiliary terrestrial network itself, that is, the terrestrial infrastructure, thereby reducing the power radiated by at least one radio terminal. In particular, in some embodiments, the aggregated radiated power controller is configured to combine in diversity signals that are received from at least one radio terminal by at least two auxiliary ground components and / or by an auxiliary ground component and at least one system auxiliary antenna, thereby reducing the power radiated by at least one radio terminal. The connection margin and / or structural attenuation margin of ATN infrastructure components can be increased by this means.

More specifically, according to the Commission's analysis of the potential for interference for co-channel satellite systems by ATN, the structural attenuation margin provided by an ATN infrastructure component on return links can be increased or maximized. Increasing or maximizing this parameter can have a direct impact on the frequency reuse and / or the number of communication channels allowed by ATN. For a given maximum EIRP of an ATN radio terminal, the available margin for an infrastructure component on a return link can be increased according to some embodiments of the invention, increasing the number of receiving antenna elements in the ATN towers of the infrastructure component and / or configuring at least some of the receiving antenna elements to operate in multiple spatially orthogonal dimensions. This approach can produce an infrastructure component capable of providing Φ dB of structural attenuation margin in routing connections and Ψ dB of structural attenuation margin in return connections, where Ψ&gt; Φ. At the limit when Ψ -&gt; oo, the radio terminal EIRP approaches zero and thus makes the potential for interference for a frequency satellite receiver. As such, the reuse of frequency and / or the number of co-frequency communication channels allowed by ATN can be increased.

Figure 19 is a schematic diagram of systems and methods according to embodiments of the present invention, in which the aggregate radiated power controller of Figure 18 is configured to control an auxiliary terrestrial network of Figure 19 to combine in diversity signals that are received from at least at least one radio terminal for at least two auxiliary ground components and / or an auxiliary ground component and at least one auxiliary antenna system, hereby to reduce the radiated power through at least one radio terminal. In addition, in accordance with other embodiments of the present invention, embodiments of Figure 19 can be used to increase the connection margin in a satellite radio terminal system that includes an ATN, independent of an aggregated radiated power controller.

Referring now to Figure 19, an auxiliary terrestrial network 1850 includes a plurality of auxiliary terrestrial components, shown in Figure 19 as first and second auxiliary terrestrial components 1900a, 1900b, each of which communicates with at least one radio terminal 1930 through of an area that defines a respective cell 1920a, 1920b.

Still referring to Figure 19, a tower of the first ATC 1900a is configured with one or more transmit antennas and / or one or more receive antennas. As stated earlier, at least some elements including the transmitter and / or receiver antennas of the infrastructure component can be operative in more than one spatial dimension. In addition, a tower of the second ATC 1900b can be configured with one or more transmitting antennas and / or one or more receiving antennas with at least some of the antenna elements operative in more than one spatial dimension. The first ATC 1900a and the second ATC 1900b, including the illustrative infrastructure component of Figure 19, may be adjacent to ATCs. Each ATC in a set of ATCs, which may include an infrastructure component, can have an associated cell 1920a, 1920b, which defines a cell edge within which the ATC is configured to serve at least one 1930 radio terminal. A radio terminal that can be close to the cell boundaries / edges of at least two adjacent ATCs, as illustrated in Figure 19, can be served simultaneously by at least two adjacent ATCs 1900a, 1900b.

Therefore, an infrastructure component including at least two adjacent ATCs, as illustrated in Figure 19, can be configured to use one or more antenna elements per ATC to receive and process transmissions from the radio terminal, which can increase the return link strength and / or return link margin available. For example, as shown in Figure 19, a base station processor 1930 from the second base station 1900b can be configured to continue transmissions that are received at the second base station 1900b from the radio terminal 1930 to a diversity receiver 1902 at the first base station

1900a via a wired and / or wireless terrestrial connection 1940. The diversity receiver can also be located, at least in part, outside the first base station 1900a. The diversity receiver 1902 can be used to combine the signals that are received at the second base station 1900b and the signals that are received at the base station 1900a from radio terminal 1930, thereby increasing the strength of the return link and / or the available return link margin. As such, the available return linkage margin and / or structural attenuation margin provided by the infrastructure component can be increased, facilitating, by closed-loop power control of the radio terminal by the infrastructure component, a reduction in power output from the radio terminal, thereby reducing the potential for interference to a co-frequency system such as a co-frequency satellite system.

To further increase or increase the available return link margin and / or return link structural attenuation margin that can be provided by an infrastructure component, in accordance with other embodiments of the present invention, at least one antenna system additional auxiliary 1910a-1910d can be arranged in the area / space between the cell border and the base station tower of at least one ATC including the infrastructure component. Figure 19 illustrates an infrastructure component configuration including two auxiliary antenna systems per ATC of the infrastructure component. However, more or less auxiliary antenna systems 1910a-191 Od can be used.

Still referring to Figure 19, a diversity receiver 1902 can be configured to accept and process signals derived from the antenna systems of the first ATC 1900a, auxiliary antenna system 1910a, auxiliary antenna system 1910b, and a 1930 base station processor associated with the second ATC 1900b. Signals derived from the auxiliary antenna systems 1910a and / or 1910b and / or the ATC tower antenna system 1900a can be sent to the diversity receiver 1902 over physical connections and / or wirelessly. Similarly, signals derived from auxiliary antenna systems 1910c and / or 191 Od and / or the ATC tower antenna system 1900b can be sent to the base station processor 1930 over physical connections and / or wirelessly.

The 1930 base station processor may also include a diversity receiver. The 1902 diversity receiver and / or 1930 base station processor can be configured to combine signals according to any conventional optimal and / or sub-optimal performance index such as, for example, maximum ratio combination. Auxiliary antenna systems 1910a-l910d can be configured to receive and / or transmit to / from 1930 radio terminals. Embodiments where auxiliary antenna systems are configured to transmit to radio terminals can increase the available routing link margin and / or the routing link structural attenuation margin of the infrastructure component.

Therefore, a first auxiliary terrestrial component for a satellite radio terminal system according to some embodiments of the present invention includes a subsystem, such as a base station tower 1900a, which is configured to communicate over land with a plurality of 1930 radio terminals substantially across the same frequency bands and / or air interfaces when the radio terminals communicate with a space-based component. A diversity receiver, such as the diversity receiver 1902, is configured to combine in diversity the signals from a 1930 radiotelephone that are received by the first auxiliary ground component 1900a and / or by at least a second auxiliary ground component 1900b, and / or by a 1910 auxiliary antenna system.

The auxiliary antenna system may be located in the first cell 1920a, such as auxiliary antenna systems 1910a, 1910b, or may be included outside the cell, such as auxiliary antenna systems 1910c, 19lOd. These embodiments can also be used to increase the bonding margin, independent of control by an aggregated radiated power controller.

In conclusion, an auxiliary terrestrial network can communicate over land with a plurality of radio terminals through a plurality of frequency bands and / or a plurality of air interfaces, while the aggregate radiated power and / or power spectral density , through any predetermined frequency band, can be limited to a predefined maximum.

In the drawings and specification, embodiments of the invention have been exposed and, although specific terms are used, they are used in a generic and descriptive sense only and not for purposes of limitation, the extent of the invention being published in the following claims.

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