An adaptive method for channel assignment in a cellular communication system

The technical field to which the invention belongs The method of adapting this channel allocation relates to the allocation of traffic channels in radio communication systems, especially cellular, radio local loops, and personal communication systems having a base station and a set of subscriber stations. Description of Related Technology A typical cellular remote communication system cell receives an incoming telephone terrestrial line and is broadcast on a radio frequency (RF) carrier by an antenna system in an area designated to be covered by the cell. It is configured around a cell station (often referred to as a base station) equipped with a multiplex transmitter to multiplex the incoming voice line. Each set of individual subscriber stations is equipped to receive the broadcast modulation carrier and multiplex the specific channels that carry the data that is scheduled to be received. Often, two-way conversations are supported by a full-duplex transmission scheme on each traffic channel. Therefore, in the context of full-duplex transmission schemes, labeled traffic channels will be used. An uplink traffic channel is a part of a traffic channel that carries data from a subscriber station to a cell station, and a downlink traffic channel is a part of a traffic channel that carries data from a cell station to a subscriber station. In a typical wireless communication system, the allocated RF frequency bandwidth is shared by a plurality of subscribers using various multiplex access technologies. Frequency division multiple access (FDMA) and time division multiple access (TDMA) techniques are typically used to share bandwidth allocated to multiple subscribers. FDMA subdivides the available bandwidth into multiple secondary bands. Each secondary band accommodates a carrier wave modulated by subscriber data. In TDMA, multiplex transmission of multiple subscribers is performed by time division in which each subscriber included in one connection is assigned a periodic time slot for transmitting the data as a packet. Nowadays, each subscriber is digital Code division multiple access (CDMA) is used to accommodate multiple subscribers on a single carrier (or subcarrier) to which a code waveform used to modulate a carrier is assigned to each bit of data. Has been introduced. Each active subscriber with an allocation code waveform taken from a set of orthogonal waveforms can separate (demodulate) the system into individual subscriber transmissions. Cellular communication systems are RF bandwidth allocated in systems using FDMA, TDMA, and / or CDMA methods (Roy III et al., US Pat. No. 5,515, It may include the use of recently introduced Spatial Split Multiple Access (SDMA) technology, which can increase the capacity of the subscriber system by using the antenna array of the cell station without increasing (378). .. SDMA leverages subscriber spatial distribution to increase the available system capacity. Since subscribers tend to be distributed across cell areas, each subscriber has how the cell station antenna array receives signals from the subscriber cell station antenna array and how the subscriber cell station antenna array It will have its own spatial sign that characterizes what it signals to. As a result, effective antenna gain in or near each active subscriber is optimized, i.e., a maximum lobe is created in or near each direction, and also. The cell station radiates the cell station antenna array by determining the spatial sign so that each lobe is narrow enough so that each active subscriber can be separated at the cell station for both transmission and reception. It has a potential to control the pattern. The data required to perform SDNA (called the subscriber's spatial sign) is empirically obtained from transmissions received at the cell station from each active subscriber. In the context of the present invention, non-spatial multiplexing (eg, FDMA, TDMA, and CDMA) is referred to as SDMA when used in combination with a controllable antenna array pattern controlled by using spatial signs. Please note. (In fact, spatial signs and antenna arrays can be used in non-spatial division multiplexing access system configurations to improve communication between cell stations and subscribers using spatial signal processing techniques. Labeled SDMA will also be used in the following description of the invention.) The actual system can consist of one or several combinations of CDMA, FDMA and TDMA technologies. For example, FDMA and TDMA The combination of techniques can be used in a system in which a set of secondary bands is further subdivided into time slots. When using spatial signs, one or more subscribers can be allowed to use a given packet time slot if the antenna array is an effective radiation pattern. For example, as a result of the effective radiation pattern of the first subscriber, there is a relatively low energy "zero" near the second subscriber that shares the packet time position, and the spatial sign of the second subscriber is the first. If the result is "zero" near the subscriber, simultaneous RF packet transmission will not interfere with reception at the two subscriber stations. Also, transmissions from the two subscribers to the cell station can be separated at the cell station. Under these ideal conditions, spatial signs are said to indicate "orthogonal" implementations. The concept of orthogonality also applies to FDMA and TDMA systems. All subcarrier channels are orthogonal to each other if each subcarrier in FDMA is completely separated so that the modulated data in any subcarrier does not affect the data that modulates any other subcarrier. There is. Similarly, in a TDMA system, channels are orthogonal to each other if each subscriber channel assigned packet data does not affect other active channels. Orthogonality can be broken in each of these multiple access systems. For example, interference occurring within a channel can be due to carrier frequency offsets and imperfect filters in FDMA systems, clocking errors and instability in TDMA systems, synchronization inaccuracies or RF multipaths in CDMA systems, and SDMA systems. It results from antenna pattern leakage caused by an antenna array of finite specifications. In a real system that may contain hundreds of subscriber stations, the design of the system may require complexity and cost, so perfect orthogonality between all subscriber stations may not be guaranteed. .. The basic motivation for using a cellular system is Reuse of the same RF spectrum in cell areas assigned to different positions. This principle of frequency reuse causes interference between cells, which, if not carefully controlled, severely degrades the quality of communication and ultimately limits the capacity of the system. Due to the fragile nature of orthogonality and the interference caused by cellular frequency reuse, all cellular multiplex access communication systems have the disadvantage caused by imperfect orthogonality between channels when new subscriber connections are added to the system. Need a method for channel allocation that minimizes the impact. Also, since the basic means of minimizing interference is the management of radiated power, the radiated power used at both subscriber and cell stations to minimize any interference that occurs in any practical multiplex access communication system. Is important to minimize. Also, both practical implementations need to be aware that RF transmission in one cell can create interference in other cells in the vicinity, and are perfectly orthogonal between neighboring cellular systems. Since the nature is generally unrealistic and direct real-time communication between adjacent cell stations would not be possible, a further need for a cellular system is to operate one cellular system and another in the vicinity. It is to provide a way to minimize the adverse effects of any interference that occurs in the system. Real-time communication between cells between cell stations may not exist or may not be possible, so minimize the adverse effects of intercellular interference, even without direct real-time communication between cell stations. Need to think. A specific example of an existing protocol for establishing a connection (Figure 1) between a subscriber station and a cell station in a cellular communication system is a radio approved at the Association of Radio Industries and Businesses in December 1995. The ones used in the "personal mobile phone system" described in RCRST D-28, the preliminary standard of the Association of Radio Industries and Businesses (ARIB), 2nd edition, can be mentioned. A The system described in the RIB Preliminary Standard, Second Edition, is a predetermined system for communicating by RF carrier between multiple geographically dispersed personal mobile phone stations (PSs) and cell stations (CS). A digital wireless personal communication system for servicing PSs in cells and for interfacing with standard telecommunications circuit equipment. The system consists of (a) 77 RF carriers that exceed the public system RF band at 1895-1918 MHz, separated by 300 kHz, and (b) phase shift keying that is a multiple of π / 4 radian to each symbol period. Horizontal axis phase shift keying (QPSK) modulation using, (c) TDMA-TDD (time split multiple access, time split double) RF access for 4 dual communications per RF carrier, and (d) 384 kbits / s Includes the signal transmission rate of (e) and a frame length of 5 ms, with 120 symbols per slot (including protection bits). Figure 2 shows the control sequence for setting up and establishing an incoming call from CS to PS. This incoming call connection establishment phase is a signal control channel (1) by sending a CS paging on the selected PS paging channel (PCH) that requires an incoming connection and (2) a link channel establishment request. The response of the selected PS on SCCH) and the PS request of CS by (3) selecting the traffic channel (TCH) and sending the TCH selected as the link channel (LCH) allocation to PS on SCCH. And (4) the selected PS switches to the assigned LHC to send a series of synchronized (SYNC) burst signals followed by a series of idle traffic bursts, and (5) successfully. Once the synchronization signal is detected, the CS will send a series of SYNC bursts over the LCH, followed by a series of idle traffic bursts, and then proceed to establish a connection with an incoming call to the CS, which is required. Deaf Includes responding by eliciting additional optional signals (eg, encryption and user authentication). PCH , CS is a one-way downlink channel from one point to multiple points (point-to-multipoint) that transmits the same information to all PSs in the paging area. SCCH is a bidirectional point-to-point channel that sends the information needed for a call connection between a CS and a PS. TCH is a point-to-point bidirectional channel for transmitting user (subscriber) information. The problems with the current procedure above are that the current procedure does not provide the appropriate transmitter output level settings for each connection and the effects of interference that may result from new connections to current subscribers. Do not work on. Figure 3 shows the control procedure for establishing an uplink connection initiated by the PS requesting the establishment of a connection with the CS. The stages are (1) PS sends a link channel establishment request on the signal control channel (SCCH), and (2) CS selects the traffic channel (TCH) and is selected as the link channel (LCH) allocation. The stage of responding to the PS request by sending the TCH to the PS via SCCH, and (3) switching to the LCH to which the PS is assigned, followed by a series of idle traffic bursts followed by a series of synchronized (SYNC) burst signals. When the transmission stage and (4) successfully detect the synchronization signal, the CS sends a series of SYNC bursts over the LCH, followed by a series of idle traffic bursts, and then the connection with the incoming call to the CS. Includes the steps of proceeding to establishment and responding by eliciting additional optional signals (eg, encoding and user authentication) that may be required. Similar to the procedure for establishing a downlink connection, the procedure for establishing an uplink connection has the same drawbacks: how to establish the transmitter output level required for proper communication and the current procedure. It has the drawback of lacking a way to assess the impact of interference created by establishing new connections to the user. The control procedures used to establish a connection with a single PS are common Use regular and individually assigned time slots. Figure 4 shows the time slot allocation used for transmission and reception in the TDMA-TDD system. The time structure of each TDD carrier is organized into 5ms frames, each divided into 8 segments. Each segment supports a one-way audio channel of 32kbits / s (excluding overhead). Figure 4 shows an example of activity in a common 5ms frame when two PSs (PS (1) and PS (2), assigned to slots 2 and 4, respectively) are communicating with CS. is there. Normally, the first four slots are allocated for transmission by CS and therefore for reception of the PS to which the transmission is directed. The last 4 slots are used for CS reception and PS transmission. The slot marker I represents an idle slot. The slot indicator T (.) Represents a transmission between the slots and the indicator R (.) ) Represents reception. Therefore, the frame of indicator (a) represents the activity of CS, that is, in slots 2 and 4, CS sends to PS (1) and PS (2), respectively, and in slots 6 and 8, CS sends PS, respectively. I'm listening to (1) and PS (2). In PS (1), slot 2 is used to receive the corresponding CS slot transmission and slot 6 is used to transmit to the CS slot. Similarly, frame (c) represents the receiving and transmitting activity of PS (2). Therefore, each frame can handle up to four bidirectional communications between the CS and the four PSs. Outline of the Invention The present invention directs a method for making a connection in a cellular system using multiplex transmission technology in order to make effective use of the available bandwidth specified by law. The method is part of a new protocol or an addition to an existing protocol for establishing a connection between a cell station and a subscriber station. In addition to existing protocols, this method is fully compatible with the standard protocols used in cellular systems and is completely invisible to all users of current cellular systems. The method for establishing an incoming call connection from CS to the selected PS in the cellular system in response to a connection request from an external communication network connected to CS is as follows: (1) CS is a downlink connection. Paging on the paging channel (PCH) of the selected PS, and (2) the selected PS responding to the signal control channel (SCCH) by sending a link channel establishment request. (3) The CS responds to the PS request by selecting the traffic channel (TCH) as the temporary link channel (LCH) and transmitting the temporary LCH allocation to the PS via SCCH, and (4) the selected PS. Switches to the assigned LCH, repeatedly sends a synchronized (SYNC) burst signal using a given initial output level for the initial transmission of the SYNC burst, and repeats until the SYNC burst is successfully received from the CS. Upon receiving a SYNC burst), the CS calculates the required PS transmit output based on the time delay between the transmission of the CS's tentative link channel allocation and the successful reception of the appropriate quality PS's SYNC burst. The CS then responds by sending a series of idle traffic bursts followed by a SYNC burst on the LCH, using the PS transmit output calculated as a guide for the CS transmission output required for proper communication with the PS. It includes the steps of initiating a connection with an incoming call to CS after calling all required additional optional protocols (eg encryption and user authorization). With this method, the appropriate PS transmission output level required for communication with CS is established. As the subscriber output level is increased little by little, the subscriber output level corresponding to the CS reception of the aptitude SYNC burst can be close to the minimum desired PS transmit output required for the connection. Sending a known test pattern (eg PHS idle traffic burst) will promptly warn other users of the same frequency, time, code or spatial channel of the cellular system that a new connection has been established. Become. Pauses after known test patterns can be used to assess for unacceptable levels of interference in connections within a cell and to perform the required handoffs. Early warning will warn neighboring cells that new connections in neighboring cells need to reassign channels if there is an unacceptable level of interference. A similar method is used when one PS wants to establish an outgoing connection through CS. This process is already started by PS sending a link channel establishment request on SCCH, as in step (2) above, except that step (1) is not used. Same as outlined. In this method, the entire method is compatible with and does not interfere with standard protocols such as those used in personal mobile phone systems. Deviate from the scope and spirit of the invention It will be appreciated that various modifications to the above description of the present invention can be made without this. For example, the logical control channels PCH and SCCH may be the same physical channel. The particular method described above relates to a PHS system for more clearly stating the application of the present invention using a particular cellular system. It will be apparent to those skilled in the art that various changes can be made by looking at the drawings and detailed description below.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a relationship between a personal station (PS) and a cell station (CS) in a personal mobile phone system. Figure 2 shows how to establish an incoming call connection from CS to PS in a personal mobile phone system. Figure 3 shows how to establish an outgoing call connection from PS to CS in a personal mobile phone system. Figure 4 shows slot allocation for TDD frames. Figure 5 shows the bit allocation pattern for synchronization bursts. FIG. 6 shows a flow diagram of how to adapt to channel allocation. Figure 7 shows the format of GSM traffic channel packets. Detailed Description of the Invention Taking the personal mobile phone system described above as an example, a method for channel allocation in a cellular system will be described. As will be appreciated by those skilled in the art, the described method is also suitable for other similar communication systems and can be applied without departing from the spirit and scope of the present invention. It is limited to those shown in the scope. As already mentioned, it is desirable to increase the system capacity when needed without adversely affecting existing communication system protocols. Ideally, the changes required for the system protocol do not require changes recognizable to the subscribers of the original system and are perfect for the original system to be extended with minimal impact on the cell station. Must be transparent and appendible to. In general, in order to reduce interference between stations that use one common frequency band, it is desirable that the minimum output required for RF connection be used, and it is also a government policy, so one PS. Whatever protocol is used to establish a connection between and CS, it should be fundamental to establish and use an acceptable low transmit output when establishing and using an RF connection. To meet this requirement, a set of experimental PS transmission output levels will be introduced by PS in stages (4) and (3) of FIGS. 2 and 3, respectively. Send SYNC burst at these stages If the initial output level used by the PS to trust is set to a safe and low level that is generally considered insufficient for CS acceptable quality reception, then the SYNC burst response (stage in Figure 2). The absence of (5) and step (4) in Fig. 3 indicates to the PS that the SYNC burst transmission output level is too low. The PS can then increase the output level each time no SYNC is received from the CS and retransmit the SYNC burst. When the SYNC transmitted by the CS is finally received, the PS knows that the transmitter output level used last was sufficient. In addition, by standardizing the initial PS transmit output level used to transmit SYNC bursts and the increment used for each retransmission (eg + 3 dB), the CS will have + 3 dB output additions. , Link channel allocation (stage (3) in Fig. 2, stage (2) in Fig. 3) and the elapsed time between the time when the SYNC burst transmitted by PS is received, so it is necessary. PS transmitter output level will be known. Due to the assumed interrelationship of transmit and receive propagation paths in a time-divided dual (TDD) system, the CS is the smallest transmitter used by the CS to communicate with the PS using the PS transmitter output level. The output level (ie, taking into account the difference in receiver sensitivity between PS and CS) can be determined. For non-TDD systems, differences in transmission and reception propagation paths could be explained by performing on-air measurements and calibrations. FIG. 5 shows the slot structure of a synchronization burst as specified by RCRSTD-28 for uplink (PS to CS) or downlink (CS to PS) synchronization. 224 bit persistent burst is R- (4bits) any 4 bit patternSS- (2bits) fixed field 10PR- (62bits) a fixed periodic preamble for both uplink and down link including. Those skilled in the art will appreciate that the synchronization signal may differ from each unique implementation of the cellular system and will depend on the form of multiplex access technology used. For example, in TDMA systems, synchronization bursts are used to determine the optimal interval for sampling incoming data, and in FDMA systems, synchronization signals are used to determine one of the subcarrier frequency offsets. , In SDMA systems, it is used to determine the spatial sign of PS required by the synchronization signal. In all cases, the purpose is to establish the parameters of multiplex transmission and signal prediction necessary to establish the highest quality connectivity. Minimizing the amount of radiated power used to form the connection is an important factor in managing interference. Interference can occur between neighboring cellular systems due to the use of common channels, or within cellular systems due to the inability to maintain perfect orthogonality between channel allocations. However, since it is difficult to guarantee the orthogonality of the new channel allocation, the connection protocol provides a practical way to minimize the potential for unacceptable levels of intra-cell interference and also manage inter-cell interference. There is a need. The basic means of managing intra-cell and inter-cell interference is to use adaptive procedures to minimize radiation output, as described above. Modeling the system is another means of providing a way to predict the outcome of a given channel allocation by calculating the impact of adding new connections on current cellular connections. The model needs to consider the appropriate radiation power, channel characteristics, and current connections that include all of the channel allocations, and predict the level of interference that would naturally be expected with the addition of new connection channels. If the system model shows that the total interference level will be below the threshold, the channel will be tentatively assigned to the new connection and empirically determine if the tentative connection will cause unacceptable interference to the existing connection. , By both CS and PS A test is sent. After the test transmission, pauses are provided at predetermined intervals to give the cellular system the opportunity to recover from unacceptable interference. If an unacceptable interference state does not occur, the temporary connection state is released and the connection is established. If not, CS must determine another behavior. The alternative forms part of the CS interference management protocol needed to manage interference from any cause. The protocol is new to reallocate temporary LCH to other channels, reallocate current connections to achieve better distribution of channel allocation, or channel capacity is unavailable at that time. It may include options such as advising the PS requesting the connection. FIG. 6 is a flow chart summarizing preferred practices 500 for adapting channels. This method is ARIB standard, version 2, RCR Designed to be compatible with the connection protocols for personal mobile phone systems described in STD-28 so that no modifications need to be made to these standards other than a simple addition that provides downward compatibility. Has been done. With Figure 6, when Method 500 for adaptive channel allocation begins, step 501 checks to see if CS is the source of the connection request, and if so, proceeds to step 502 and CS is selected by PCH. Page the PS with PCH, and then move to stage 503. In step 503, the selected PS sends a Link Channel Establishment Request (LCR) message to CS via SCCH in response to its paging. In stage 505, CS selects the best candidate Link Channel (LCH) from the available traffic channels and sends the selection over SCCH as a tentative allocation LCH. At the time of this connection, the selected PS bursts SYNC with a tentative LCH at stage 511, at a given low output level, close to the lowest possible output level, where reception quality is expected to be acceptable for CS. To send. At step 513, the selected PS checks to see if a SYNC burst is being returned from the CS indicating that the PS is using sufficient output to establish a quality reception that the CS can accept. If not, PS increases the transmitter output level at step 512 (usually + 3dB) and returns to step 511. Several 3 dB output increases ensure that the output level established in step 512 will be within the minimum 3 dB output required for quality reception. The smaller the increase in output, the closer the established output level is to the desired minimum output level (eg, a + 1 dB increase ensures that the established output level is within 26% of the minimum value). Can be done. Meanwhile, at stage 506, CS hears the PS SYNC burst transmission on the tentative LCH and enters a weight loop containing test stage 507 until the SYNC burst is received with acceptable quality. After receiving the SYNC burst, the stage On floor 508, CS calculates the CS transmit output level based on the elapsed time between the LCH allocation of CS at stage 505 and the reception of an acceptable quality SYNC burst at stage 507. (Since the transmission of PS SYNC burst is repeated at a predetermined interval (usually -5ms), the output required for the PS transmitter can be calculated, and m is the number of output increases, P.₀Is the specified initial PS transmitter output, and the output required for an increase of + 3 dB is 2.^m-1P₀Will be. ) At step 510, the CS sends a SYNC burst using the output level calculated in step 508. At stage 514, upon receiving a CS SYNC burst, the selected PS and CS perform a series of idle traffic bursts consisting of 50% duty cycle on-off bursts, typically at a rate of 200 bursts per second. Send continuously for 10 burst intervals. (One PHS idle traffic burst signal is used to indicate that a given channel does not carry any user data.) After transmitting the idle traffic burst, at stage 515, resulting from the test signal transmission at stage 514. A pause of a predetermined time (usually 50 ms) is introduced to cause the system to report any unacceptable interference. If inter-cell interference occurs (stage 516) and communication between cell stations is available (stage 520), nearby CS will stage to report all unacceptable interference to CS using a new call. You can use poses at 515. Without CS communication between cells (step 520), nearby cells experiencing unacceptable interference at step 521 to minimize the "cost" of the resulting interference at step 521. , Call the prescribed procedure from the interference management protocol. At stage 517, CS uses a new call to check for unacceptable interference with any of the existing connections (including any neighboring cells with which it is communicating), otherwise CS at stage 518. , Treat the temporarily assigned LCH as a new connection. Otherwise, at step 518, CS calls a predetermined procedure from the interference management protocol to minimize the "cost" of the resulting interference. As is well known in the prior art, interference management protocols can include a number of coordination procedures such as channel reallocation and / or handoffs to other neighboring CSs. A 50% duty cycle idle traffic burst is a given test to signal that a new connection has been established. Alternatively, other signals used as examples of test signals but using different sequences of idle channel traffic bursts with no interspersed signal intervals may be used. An idle traffic burst indicates that user data is not carried on a given channel, but a given sequence of idle traffic bursts with no interspersed signal intervals can also be designed to carry additional non-user data information. For example, a test signal with a particular sequence pattern may be selected to inform all stations that the message attempting to establish a connection is an urgent (eg "911" call) message and should be given top priority. You can also. This allows any cellular station that experiences an unacceptable level of interference to call the interference protocol suitable for the highest priority message. Multiple priority message levels can also be created by defining a well-defined set of sequence patterns for scattered idle traffic bursts and no-signal intervals. It should be understood that certain characteristics of the PHS system are used for the purpose of clearly explaining the method shown in Figure 6. However, as already mentioned, the methods described can also be applied to other cellular systems, the applicability of which will be apparent to those skilled in the art. This method is widely used as described in "GSM System for Mobile Communications" co-authored by Mourley, M and Poutet, M, published by the author in 1992, Palais F-91120, Louise Brunoy Street, 49, France. Cellular communication system It can be applied to cellular systems such as GSM (Global System for Mobile Communication). For example, GSM includes bidirectional data and a traffic channel (TCH) packet configuration for incoming signaling, as shown in FIG. This configuration can be used to send interference test signals for the same purpose as idle traffic bursts in PHS, i.e., new connections are being established. It can be used as an early warning, to determine if the connection causes unacceptable interference. The THC cycle in Figure 7 consists of 26 bursts over a 120 ms period, organized into two consecutive 24 data bursts D at positions 0-11 and 13-24. Burst X at position 12 is assigned for low speed associated control channel (SACCH) bidirectional signaling, and burst O at position 25 is a blank burst where no transmission occurs. Signaling within the GSM connection can be tuned in two ways: using the SACCH connected to the burst of user data, or when no user data is being transmitted, predetermined during the initial setup of the call. It is a method of using one or more whole cycles to signal on one of the channels. The GSM receiver can distinguish between the two modes by reading the binary information transmitted on the TCH called the "steering" flag (quoted by Mourley et al., P. 190). Therefore, either the SACCH burst or the full GSM TCH cycle (Figure 7), functionally the idle traffic burst test signal of the PHS, during the initial setup of the call as described earlier and in step 514 of Figure 6. Can be used for bidirectional transmission of test signals equivalent to. The steps to determine and pause the transmitter output level are independent of the communication protocol, so the entire method can be added to GSM's cellular system without changing the existing protocol. .. Although the method described for adapting channels has been described exclusively for specific cellular communication systems for clarity of explanation, those skilled in the art deviate from the spirit and scope of the invention. Without notice, it is clear that it can be applied to other similar communication systems such as wireless local area networks (LANs), and the present invention is limited solely by what is presented in the claims below. .. Either of the TCH cycles (Fig. 7) can be used for bidirectional transmission of the test signal, which is functionally equivalent to the idle traffic burst test signal of PHS. The steps to determine and pause the transmitter output level are independent of the communication protocol, so the entire method can be added to GSM's cellular system without changing the existing protocol. .. Although the method described for adapting channels has been described exclusively for specific cellular communication systems for clarity of explanation, those skilled in the art deviate from the spirit and scope of the invention. Without notice, it is clear that it can be applied to other similar communication systems such as wireless local area networks (LANs), and the present invention is limited solely by what is presented in the claims below. ..