Preamble based uplink power control for lte

(54) Title: UPLINK POWER CONTROL (57) Summary: BASED ON PREAMBLE FOR AN LTE SYSTEM.

(30) Unionist Priority: 13/02/2008 us 12 / 030,333,

02/14/2007 US 60 / 889,931 (73) Owner (s): Qualcomm Incorporated (72) Inventor (s): Durga Prasad Malladi, Juan Montojo (74) Attorney (s): Montaury Pimenta, Machado &

Lioce S / C Ltda (86) International Order: pct US2008053922 from

02/14/2008 (87) International Publication: wo 2008 / i0i055de

21/08/2008

500

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UPLINK POWER CONTROL BASED ON LTE PREAMBLE

CROSS REFERENCE TO RELATED ORDERS

This application claims the benefit of US provisional patent application Serial No. 60/889 931, entitled METHOD AND EQUIPMENT FOR POWER CONTROL THAT USE PREAMBLE FOR POWER CONTROL, which was filed on February 14, 2007. All of the aforementioned application is hereby incorporated by reference.

BACKGROUND

I. Field

The following description refers in general to wireless communications and, more specifically, to the control of uplink power levels (UL) used by access terminals in a wireless communication system based on Long Term Evolution (LTE) .

II. Background

Wireless communication systems are widely used to provide several types of communication; for example, voice and / or data can be provided through such wireless communication systems. A typical wireless communication system, or network, can give multiple users access to one or more shared resources (such as bandwidth, transmission power,...). For example, a system can use a variety of multiple multiple access techniques, such as Frequency Division Multiplexing (FDM). Time Division Multiplexing (TDM), Code Division Multiplexing (CDM), Orthogonal Frequency Division Multiplexing (OFDM), Single Carrier Frequency Division Multiplexing (SÇ-FDM) and others. In addition, the system can conform

2/64 to specifications such as the third generation partnership project (3GPP), long term evolution 3GPP (LTE), etc.

Generally, wireless multiple access communication systems can simultaneously support communication to multiple access terminals. Each access terminal communicates with one or more base stations through transmissions on the forward and reverse links. The direct link (or downlink) refers to the communication link from the base stations to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the base stations. This communication link can be established through a single input and single output system (SISO), multiple inputs and single output (MISO), single output and multiple outputs (SIMO) or multiple inputs and multiple outputs (MIMO ).

Wireless communication systems often use one or more base stations and sectors in them that provide a coverage area. A typical sector can transmit several data streams for broadcast, multicast and / or unicast services, in which a data stream can be a data stream that may be of interest to an independent reception to an access terminal. An access terminal within the coverage area of ​​such sector can be used to receive one, more than one or all of the data streams carried by the composite stream.

Likewise, an access terminal can transmit data to the base station or to another access terminal. With many access terminals transmitting signal data in close proximity, power control is important to obtain sufficient signal-to-noise ratios (SNRs) at different data rates and bandwidths

3/64 transmission for communications via uplink. It is desirable to keep the overhead incurred in transmitting the power settings to these access terminals as low as possible while achieving the objectives mentioned above. The reduction in overhead in support of power control settings makes it difficult to guarantee an adequate reception security level in all situations and, most notably, in situations with prolonged periods of UL data inactivity.

SUMMARY

The following is a simplified summary of one or more modalities in order to obtain a basic understanding of these modalities. This summary is not an extensive panoramic view of all the modalities contemplated and is neither intended to identify key or critical elements of all modalities nor to delineate the scope of any or all modalities. Its sole purpose is to present some concepts of one or more modalities in a simplified form as an introduction to the more detailed description that is presented below.

According to one or more modalities and their corresponding disclosure, several aspects are described in connection with facilitating the use of power control preambles with aperiodic closed-loop power control techniques in a wireless communication environment. An uplink lease can be transferred via a downlink (a first uplink lease after inactivity on the uplink, for example), and a power control preamble can be sent via an uplink in response to the uplink grant. According to an example, the transmission of the power control preamble can be explicitly programmed and / or implicitly programmed. The preamble to control

4/64 power can be transmitted at a power level determined by an access terminal that uses an open loop power control mechanism. A base station can analyze the power control preamble and generate a power control command based on it to correct the power level used by the access terminal. The access terminal can then use the power control command to adjust the power level for transmitting uplink data.

According to related aspects, a method is described here that facilitates the generation of a power control preamble for use in a wireless communication environment. The method may include receiving an uplink lease from a base station, the uplink grant being a first uplink grant after the uplink is down. In addition, the method may comprise transmitting a power control preamble to the base station with a power configuration based on open loop power control. In addition, the method may include receiving a power control command from the base station, the power control command by adjusting the power setting. The method may also include transmitting data to the base station with the adjusted power setting.

Another aspect concerns wireless communication equipment. Wireless communication equipment may include a memory that holds instructions related to obtaining a uplink lease from a base station, the uplink grant being a first uplink grant after uplink inactivity, determining a level of control for transmitting the preamble control system based on an open loop assessment, send a power control preamble to the base station when

5/64 power level, receive a power control command from the base station, change the power level based on the power control command, and send an uplink data transmission to the base station at a power level that has been changed according to the power control command. In addition, wireless communication equipment may include a processor, attached to the memory, configured to execute instructions held in memory.

Yet another aspect refers to wireless communication equipment that allows the use of power control preambles in a wireless communication environment. Wireless communication equipment may include a device to obtain an uplink lease, the uplink grant being a first uplink grant for uplink inactivity. In addition, subsequent wireless communication equipment may include a device for transferring an uplink power control preamble to a selected power level as a function of an open loop power control estimate. Furthermore, wireless communication equipment may comprise a device for obtaining a power control command that changes the power level. In addition, wireless communication equipment may include a device for transmitting uplink data at the changed power level.

Yet another aspect refers to a machine-readable medium that has machine executable instructions stored in it to obtain an uplink lease, the uplink grant being a first uplink grant after the uplink is inactive; transfer a power control preamble to a selected power level as a function of a control estimate

6/64 open-loop power; obtain a power control command that changes the power level; and transmit uplink data at the changed power level.

According to another aspect, equipment in a wireless communication system can include a processor, where the processor can be configured to obtain an uplink lease from a base station, the uplink lease being a first uplink lease subsequent to downtime on the uplink. In addition, the processor can be configured to determine a power level for transmission of the power control preamble based on an open loop evaluation. The processor can also be configured to send a power control preamble to the base station at the power level. In addition, the processor can be configured to receive a power control command from the base station. The processor can also be configured to change the power level based on the power control command. In addition, the processor can be configured to send an uplink data transmission to the base station at the changed power level.

According to other aspects, a method is described here that facilitates the evaluation of power control preambles for use with power control in a wireless communication environment. The method may include transmitting an uplink lease to an access terminal. The method may also include receiving a power control preamble sent from the access terminal at a fixed power level based on open loop power control. In addition, the method may comprise generating a power control command based on an analysis of the power control preamble, the power control command correcting the power level of the

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an access terminal control level. The method may also include transmitting the power control command for access. In addition, the method can transmit data from uplink env: access to the corrected power level.

Yet another aspect refers to a flexible element communication equipment that can include a memory that holds instructions related to transferring an uplink lease, obtaining a power control preamble sent via a power uplink determined by a power mechanism open-loop, obtain a power control command that corrects the power level based on an assessment of the power control preamble, send the power control command via a downlink, and obtain an uplink data transmission sent at the corrected power level. In addition, wireless communication equipment may include a processor, attached to the memory, configured to execute instructions held in memory.

Yet another aspect refers to wireless communication equipment that allows the obtainment of power control commands based on preamble of power control for use by access terminals in a wireless communication environment. Wireless communication equipment may include a device to send an uplink lease via a downlink. In addition, wireless communication equipment may include a device for obtaining a power control preamble sent at a power level determined from an open-loop estimate. The wireless communication equipment may additionally comprise a device for sending a power control command that corrects the

8/64 power level. In addition, wireless communication equipment may include a device for obtaining an uplink data transmission at the corrected power level.

Yet another aspect refers to a machine-readable medium that has executable instructions per machine stored to send an uplink lease via a downlink; obtain a power control preamble sent at a power level determined from an open-loop estimate; send a power control command that corrects the power level; and obtain an uplink data transmission at the corrected power level.

According to another aspect, equipment in a wireless communication system can include a processor, where the processor can be configured to transmit an uplink lease to an access terminal. The method can also be configured to receive a power control preamble sent from the access terminal at a fixed power level based on open loop power control. In addition, the processor can be configured to generate a power control command based on an analysis of the power control preamble, the power control command correcting the power level of the access terminal. In addition, the processor can be configured to transmit the power control command to the access terminal. In addition, the processor can be configured to receive an uplink data transmission sent from the access terminal at the corrected power level.

In order to achieve the foregoing and related purposes, the modality or modalities comprise the following characteristics completely described and

9/64 specifically noted in the claims. The following description and the attached drawings present in detail certain illustrative aspects of the modality or modalities. These aspects, however, indicate only some of the different ways in which the principles of different modalities can be used, and the modalities described are intended to include all aspects such and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a wireless communication system according to several aspects presented here.

Figure 2 shows an exemplary system that controls the power level (s) used by the access terminal (s) in an LTE-based wireless communication environment.

Figure 3 shows an exemplary system that periodically corrects the uplink power level used by an access terminal.

Figure 4 shows an exemplary system that periodically transfers power control commands to access terminals in an LTE-based wireless communication environment.

Figure 5 shows an exemplary system that uses preamble-based power control in an LTE-based wireless communication environment.

Figure 6 shows an exemplary system that groups access terminals to send power control commands via a downlink.

Figure 7 shows exemplary transmission structures for communicating power control commands to groups of access terminals.

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Figure 8 shows an exemplary timing diagram for a periodic uplink power control procedure for LTE.

Figure 9 shows an exemplary timing diagram for an aperiodic uplink power control procedure for LTE.

Figure 10 shows an exemplary timing diagram for an LTE uplink power control procedure that leverages a power control preamble.

Figure 11 shows an exemplary methodology that facilitates the generation of a power control preamble for use with power control in a wireless communication environment based on Long Term Evolution (LTE).

Figure 12 shows an exemplary methodology that facilitates the evaluation of power control preambles for use with power control in a wireless communication environment based on Long Term Evolution (LTE).

Figure 13 shows an exemplary access terminal that facilitates the use of power control preamps with power control in an LTE-based wireless communication system.

Figure 14 shows an exemplary system that facilitates the analysis of power control preambles for use with power control in a wireless communication system based on LTE.

Figure 15 shows an exemplary wireless network environment that can be used in conjunction with the various systems and methods described here.

Figure 16 shows an exemplary system that allows obtaining power control commands with

11/64 based on power control preambles for use by access terminals in a wireless communication environment.

Figure 17 shows an exemplary system that allows the use of power control preambles in a wireless communication environment.

DETAILED DESCRIPTION

Several modalities are now described with reference to the drawings, in which the same reference numbers are used to refer to the same elements everywhere. In the following description, for the purpose of explanation, numerous specific details are presented in order to obtain a complete understanding of one or more modalities. It may be evident, however, that such mode (s) can be put into practice without these specific details. In other cases, structures and devices notoriously known in the form of a block diagram in order to facilitate the description of one or more modalities.

As used in this application, the terms component, module, system and the like are intended to refer to an entity related to a computer, or hardware, firmware, a combination of hardware and software, software or software running. For example, a component can be, but is not limited to, a process that runs on a processor, a processor, an object, an executable, a flow of execution, a program and / or a computer. By way of illustration, both an application that runs on a computing device and the computing device can be a component. One or more components can reside within a process and / or flow of execution, and a component can be located on a computer and / or distributed between two or more

12/64 computers. In addition, these components can be executed in a variety of media that can be read by a computer and have different data structures stored in them. Components can communicate via local and / or remote processes, for example, according to a signal that has one or more data packets (such as, for example, data from a component that interacts with another component in a local system, distributed system and / or over a network, such as the Internet, with other systems by means of the signal).

In addition, several modalities are described here in connection with an access terminal. An access terminal can also be called a system, subscriber unit, subscriber station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent or equipment user (UE). An access terminal can be a cell phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a wireless local loop station (WLL), a personal digital assistant (PDA), a handheld device wirelessly capable, a computing device or other processing device connected to a wireless modem. In addition, several modalities are described here in connection with a base station. A base station can be used to communicate with an access terminal or terminals and can also be referred to as an access point, Node B, eNode B (eNB) or some other terminology.

In addition, several aspects or features described here can be implemented as a method, equipment or industrial product using standard engineering and / or programming techniques. The term industrial product as used here

13/64 used is intended to cover a computer program accessible from any device, carrier or medium that can be read by computer. For example, computer-readable media may include, but are not limited to, magnetic storage devices (such as, for example, hard disk, floppy disk, magnetic strips, etc.), optical discs (such as, for example, compact disc (CD), digital versatile disc (DVD), etc.), smart cards and flash memory devices (such as, for example, EPROM, card, stick, key drive, etc.). In addition, the various storage media described herein may represent one or more devices and / or other machine-readable means for storing information. The term machine-readable means may include, but is not limited to, wireless channels and various other means capable of storing, containing and / or carrying instruction (s) and / or data.

Referring now to Figure 1, a wireless communication system 100 is shown according to the various modalities presented here. System 100 comprises a base station 102 which can include several groups of antennas. For example, one group of antennas can include antennas 104 and 106, another group can comprise antennas 108 and 110 and an additional group can include antennas 112 and 114. Two antennas are shown for each antenna group; however, more or less antennas can be used for each group. Base station 102 may additionally include a chain of transmitters and a chain of receivers, each of which may in turn comprise a series of components associated with the transmission and reception of signals (such as, for example, processors, modulators, multiplexers, demodulators) , demultiplexers, antennas, etc.), as will be understood by those skilled in the art.

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The corresponding sector of the base station 102 can communicate with one or more access terminals, such as access terminal 116 and access terminal 122; however, it should be understood that base station 102 can communicate with substantially any number of access terminals similar to access terminals 116 and 122. The access terminals 116 and 122 can be, for example, cell phones, smart phones, laptops, handheld communication devices, radio satellites, global positioning systems, PDAs and / or any other device suitable for communication through the communication system. wireless communication 100. As shown, access terminal 116 is in communication with antennas 112 and 114, where antennas 112 and 114 transmit information to access terminal 116 via a direct link 118 and receive information from access terminal 116 via a reverse link 120. As shown, access terminal 122 is in communication with antennas 104 and 106, where antennas 104 and 106 transmit information to access terminal 122 via a direct link 124 and receive information from access terminal 122 via a reverse link 126. In a frequency division duplex (FDD) system, direct link 118 may use a different frequency band than that used by reverse link 120, and direct link 124 may use a different frequency band than that used by reverse link 126, for example. example. In addition, in a time division duplex (TDD) system, forward link 118 and reverse link 120 may use a common frequency band, and forward link 124 and reverse link 126 may use a common frequency band.

Each group of antennas and / or the area in which they are assigned to communicate can be referred to as a

15/64 sector of base station 102, or as an eNB cell. For example, groups of antennas can be designed to communicate with access terminals in a sector of the areas covered by base station 102. In communication via direct links 118 and 124, the transmission antennas of base station 102 can use beams in order to improve the signal-to-noise ratio of direct links 118 and 124 to access terminals 116 and 122. In addition, while base station 102 uses beam formation to transmit to access terminals 116 and 122 scattered randomly through a related cover, access terminals in neighboring cells may be subject to less interference compared to that suffered by a base station which transmits through a single antenna to all its access terminals.

system 100 can be a system based on Long Term Evolution (LTE), for example. In such a system 100, the corresponding sectors of the base station 102 can control the uplink power levels used by the access terminals 112 and 122. Therefore, system 100 can provide uplink power control (UL) that provides compensation for loss of path and shading (shading can change time) and compensation for loss of path and the slow over variable interference in the adjacent cell time (as, for example, since system 100 can be an LTE-based system that uses frequency reuse 1). Furthermore, system 100 can attenuate large variations in the reception power obtained at base station 102 by users (since users can be multiplexed within a common band). In addition, system 100 can compensate for variations in multipath fading at speeds

16/64 low enough. For example, the channel coherence time for 3 km / h at different carrier frequencies can be as follows: a carrier frequency of 900 MHz can have a coherence time of 400 msec, a carrier frequency of 2 GHz can have a coherence time of 180 msec, and a carrier frequency of 3 GHz can have a coherence time of 120 msec. Thus, depending on the latency and frequency of adjustments, the effects of rapid fading can be corrected with low Doppler frequencies.

System 100 can use uplink power control that combines open-loop and closed-loop power control mechanisms. According to an example, open loop power control can be used by each access terminal 116, 122 to set the power levels of a first preamble to a Random Access Channel (RACH) communication. For the first preamble of a RACH, each access terminal 116, 122 may have obtained downlink communication (s) from base station 102, and the open loop mechanism may enable each access terminal 116, 122 to select a uplink transmit power level that is inversely proportional to a receive power level related to the obtained downlink communication (s). Thus, the knowledge of the downlink can be used by the access terminals 116, 122 for uplink transmissions. The open-loop mechanism can provide rapid adaptation to marked changes in radio conditions (depending on the filtering of the receiving power, for example) through instantaneous power adjustments. In addition, the open-loop mechanism can continue to function beyond RACH processing in contrast to conventional techniques often used.

The mechanism of

17/64 closed loop can be used by system 100 once the random access procedure has been successful. For example, closed loop techniques can be used when periodic uplink resources have been allocated to access terminals 116, 122 (such as, for example, periodic uplink resources can be Physical Uplink Control Channel (PUCCH) resources or Reference Sound Signal (SRS)). Furthermore, the corresponding sectors in base station 102 (and / or in a network) can control the uplink transmission power used by access terminals 116, 122 based on closed loop control.

The closed loop mechanism used by the 100 system can be periodic, aperiodic or a combination of the two. Periodic closed loop corrections can be transmitted by the corresponding sectors at base station 102 to access terminals 116, 122 periodically (such as, once every 0.5 msec, 1 msec, 2 msec, 4 msec, .. .). For example, the frequency may depend on the frequency of uplink transmissions. In addition, periodic corrections can be single-bit corrections (such as, for example, increasing / decreasing, ± 1 dB, ...) and / or multi-bit corrections (such as, for example, ± 1 dB, ± 2 dB, ± 3 dB, ± 4 dB, ...). Thus, the power control step and the frequency of corrections can determine the maximum uplink power rate that the corresponding sectors in base station 102 (and / or in the network) can control. According to another example, periodic corrections can be sent from the corresponding sectors at the base station 102 to the corresponding access terminals 116, 122, as needed. After this example, these corrections can be transmitted periodically when triggered by a network measurement (such as, for example,

18/64 example, the receiving power (RX) outside an established range, an opportunity to send control information to a given access terminal, ...). Furthermore, aperiodic corrections can be single bit and / or multiple bits (as, for example, corrections can be multiple bits since a significant part of the overhead associated with aperiodic corrections can refer to programming corrections and not the size of the corrections). According to yet another example, aperiodic corrections can be transmitted by the corresponding sector at base station 102 to access terminals 116, 122 in addition to periodic corrections in order to minimize the overhead incurred with the transmission of these power settings.

Now referring to Figure 2, a system 200 is shown that controls the power level (s) used by the access terminal (s) in an LTE-based wireless communication environment. System 200 includes a sector at a base station 202 that can communicate with substantially any number of access terminals (not shown). In addition, the sector at base station 202 may include a received power monitor 204 that evaluates the power level (s) associated with the signal (s) obtained from the terminal (s) ) access. In addition, the sector at base station 202 may comprise an uplink power adjuster (UL) 206, which uses the analyzed power level (s) in order to generate command (s) to change the power levels of the access terminals.

Several physical channels (PHY) 208 can be activated for communication between the base station 202 and the access terminal (s); these physical channels 208 may include physical downlink channels and physical uplink channels. Examples of physical downlink channels include

19/64 (which assigns

Physical Downlink Control Channel (PDCCH), Shared Physical Downlink Channel (PDSCH) and Common Power Control Channel (CPCCH). The PDCCH is a layer I / layer 2 (LI / L2) DL control channel (PHY layer features for DL ​​or UL transmission) that has a capacity of about 30-60 bits and is protected by cyclic redundancy check (CRC ). The PDCCH can carry uplink leases and downlink assignments. PDSCH is a DL shared data channel; PDSCH can be a DL data channel shared between different users. The CPCCH is transmitted in the DL for UL power control of several access terminals. The corrections sent in the CPCCH can be single or multi-bit. In addition, the CPCCH can be a specific instantiation of the PDCH. Examples of physical uplink channels include Physical Uplink Control Channel (PUCCH), Shared Physical Uplink Channel (PUSCH), Audible Reference Signal (SRS) and Random Access Channel (RACH). PUCCH includes the Channel Quality Indicator (CQI) channel,

UL. PUSCH is

The SRS may be devoid of information and may allow the channel to be sounded on the UL in order to provide sampling of the channel through part of the total system bandwidth. It should be understood that the object claimed is not limited to these exemplary physical channels 208.

The received power monitor 204 and the UL 206 power adjuster can provide closed-loop power control for uplink transmissions via access terminals. Operation in the LTE system can cause transmissions at a given time through bandwidths that can be significantly less than the entire 200 system bandwidth. Each ACK channel and one UL shared data request channel.

20/64 access terminals can transmit over a small part of the entire bandwidth of the system 200 in one. Furthermore, frequency hops can be like this, the sector can find given time used by the access terminals; base station 202 difficulties in trying to assess adjustments to be made to the uplink power levels of the access terminals. Therefore, a suitable closed-loop power control mechanism provided by the received power monitor 204 and the UL 206 power adjuster constructs an estimate of the broadband reception power of transmissions possibly over several instants and possibly over multiple PHY UL channels. , allowing the appropriate correction of the effects of loss of path and shading regardless of the transmission bandwidth of the access terminal (s) at any time.

The received power monitor 204 constructs the broadband reception power estimate from the channel sampling based on the transmissions from the access terminal (s) in several ways. For example, the received power monitor 204 can use PUSCH for sampling. Following this example, the PUSCH transmission band is located in a given partition. A frequency diversity schedule can apply a pseudo-random hop pattern to the transmission band at the boundaries between partitions and possibly through retransmissions, in order to fully explore the frequency diversity. PUSCH transmissions that exploit frequency selective programming will not apply a frequency hopping pattern to the transmission data and therefore may require a long time to sample the channel at all (or most) frequencies. Furthermore,

21/64 frequency selective programming can trigger the transmission of an SRS or PUCCH. Frequency selective programming is a programming strategy that explores channel selectivity; for example, frequency selective programming attempts to confine broadcasts to the best sub-bands. This programming strategy may be relevant for low mobility access terminals. In addition, these transmissions are usually exclusive of frequency hopping techniques. Frequency diversity programming is a distinct programming strategy that uses the entire system bandwidth (such as, for example, minimum transmission bandwidth capacity module, ...) to naturally obtain frequency diversity. Transmissions associated with programming with frequency diversity can be associated with frequency jumps. Furthermore, frequency hops can include changing the transmission frequency of a waveform in a pseudo-random manner for frequency diversity from the point of view of a channel as well as interference.

According to another example, the received power monitor 204 can use the PUCCH to sample the UL channel and, therefore, construct the broadband reception power estimate. The PUCCH transmission band can be located on a given partition with boundary jumps between partitions at each transmission time interval (TTI). A busy band may depend on whether or not PUSCH is transmitted in a specific TTI. When the PUSCH is transmitted via a given TTI, the control information that would be transmitted via the PUCCH can be transmitted in the band with the rest of the data transmission (in order to retain the unique carrier property of the UL waveform, for example) through PUSCH. When

22/64 the PUSCH is not transmitted through a specific TTI, the PUCCH can be transmitted through a localized band set aside for PUCCH transmission at the edges of the system band.

According to another illustration, the SRS transmissions can be used by the received power monitor 204 to sample the channel and construct the broadband reception power estimate. The transmission bandwidth (over time) of the SRS can be substantially equal to the entire system bandwidth (or the minimum transmission bandwidth capacity of the access terminal (s)). At a given SC-FDMA symbol (a SC-FDMA symbol is a minimum transmission unit on the LTE UL, for example), the transmission can be located (covering a set of consecutive sub-carriers that bounce over time, for example example) or distributed (as, for example, covering the entire band of the system or a part of it, which may or may not skip,...). The received power monitor 204 constructs the broadband reception power estimate from the channel sampling across the entire system bandwidth. When there is no UL data, PUCCH transmissions occur at the edges of the system band. When there is UL data, a PUCCH transmission can be located in the band with the data transmission via PUSCH. In addition, PUSCH transmissions may not change the transmission frequency or may not jump at all to explore selective programming at UL frequency; however, to enable selective frequency programming, SRS transmissions can be triggered for FDD / TDD systems. Furthermore, when PUSCH uses programming with frequency diversity, the frequency jump is applied to transmissions.

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In addition, based on the channel sampling performed by the received power monitor 204, the UL 206 power adjuster can generate a command that can change the UL power level used by a specific access terminal. The command can be a single-bit correction (such as, for example, plus / minus, ± 1 dB,...) And / or a multi-bit correction (such as, for example, ± 1 dB, ± 2 dB , ± 3 dB, ± 4 dB, ...). In addition, the UL 206 power adjuster (and / or the sector at the corresponding base station 202) can transmit the generated command to the access terminal to which the command is intended.

In addition, the access terminals can each be associated with a specific state at a given time. Examples of access terminal states include LTE_OCIOSO, LTE_ATIVO and LTE_ATIVO_CPC. However, it should be understood that the object claimed is not limited to these illustrative states.

LTE_OCIOSO is an access terminal state in which the access terminal does not have a unique cell ID. While in the LTE_OCIOSO state, the access terminal may lack a connection to base station 202. In addition, the transition to the LTE_ATIVO state from LTE_OCIOSO can be carried out using the RACH.

LTE_OCIOSO is an access terminal state in which the access terminal has a unique cell ID. In addition, when in the LTE_ATIVO state, the access terminal can actively transfer data through the uplink and / or the downlink. Access terminals in this state have dedicated UL resources (such as, for example, CQI, SRS, which are transmitted periodically,...). According to an example, access terminals in the LTE_ATIVO state may use discontinuous transmission / discontinuous reception (DTX / DRX) procedures with a cycle that is not expected to

24/64 is much longer than approximately 20 msec or 40 msec. Access terminals in this state begin transmitting PUSCH either directly, in response to activity in the DL (such as, possibly, with a UL grant in the band with DL data or via the PDCCH) or by sending a UL request via Beyond In addition, users in this state can be access terminals with an active UL / DL data exchange taking place or access terminals that run a high Quality of Service (GoS) application (such as, for example, Voice over Internet Protocol (VoIP), ...).

LTE_ATIVO_CPC (Continuous Pack Connectivity) is a sub-state of LTE_ATIVO in which access terminals retain their unique cell ID, but in which dedicated UL resources have been released. The use of LTE_ATIVO_CPC allows the extension of battery life. Access terminals in this sub-state begin transmissions or in response to activity in the DL (as, for example, possibly with a UL grant in the band with DL data or through the PDCCH,... ) or by submitting a UL request via RACH. The initial transmission power can be based either on an open loop mechanism (such as, for example, response to activity in the DL) or on the last successful preamble (RACH, for example).

Referring to Figure 3, an exemplary system 300 is shown which periodically corrects the uplink power level used by an access terminal. System 300 includes base station 202, which communicates with an access terminal 302 (and / or any number of distinct access terminals (not shown). Access terminal 302 comprises a UL 304 power manager, which includes also a UL 306 power starter.

25/64 further, access terminal 302 includes a periodic transmitter UL 308. Base station 202 also includes received power monitor 204 and power adjuster UL 206; the received power monitor 204 also comprises a periodic corrector 310.

The periodic corrector 310 generates periodic power control commands (such as, for example, periodic transmission power control (TPC) commands, periodic corrections, ...) to be transferred to the access terminal 302. In addition, periodic broker 310 can transmit periodic power control commands to access terminal 302 (and / or to any (any) distinct access terminal (s)) at any periodicity (such as, for example) , 0.5 msec, 1 msec, 2 msec, 4 msec, ...); however, the possibility is considered that the UL 206 power adjuster and / or the base station 202 transmit such periodic power control commands. In addition, periodic corrector 310 can obtain a single-bit correction (such as, for example, plus / minus, ± 1 dB, ...) and / or a multi-bit correction (such as, for example, ± 1 dB, ± 2 dB, ± 3 dB, ± 4 dB,...). For example, if periodic corrections are sent from periodic corrector 310 at a higher frequency, then single-bit corrections are more likely to be used, and vice versa.

The UL 394 power manager controls the uplink power level used by access terminal 302 for transmissions on the uplink. The UL 304 power manager can receive periodic power control commands from base station 202 and change the uplink power level used for transmission based on the obtained commands. According to another illustration, the UL 306 power initiator can establish a

26/64 a preamble immediately send can initial uplink transmit power. The UL 306 power initiator can use an open loop mechanism to determine the initial uplink transmission power based on downlink activity, for example. In addition or alternatively, the UL 306 power initiator can assign the initial uplink power level to a power level associated with a previous success (such as, for example, previous, ...) (RACH, for example).

The UL 308 periodic transmitter periodic transmissions to base station 202 via the uplink. For example, the periodic transmitter UL 308 can operate while access terminal 302 is in the LTE_ACTIVE state. Furthermore, the periodic transmissions transferred by the UL 308 periodic transmitter can be a set of SRS transmissions; however, it should be understood that the claimed object is not thus limited, since any type of uplink transmission can be used (such as, for example, periodic CQI transmissions, periodic PUCCH transmissions, ...). Thus, the UL 308 periodic transmitter can send SRS transmissions through the uplink in order to sound the channel through the entire bandwidth of the system, since the SRS transmissions can therefore be, at the same time as enabling selective in uplink frequency, the audible signal can be used to compute closed loop corrections for UL power control. Transmissions sent by the UL 308 periodic transmitter can be received and / or used by the received power monitor 204 from base station 202 in connection with channel sampling. In addition, the UL 206 power adjuster and / or the sounder corrector; the programation

27/64 periodic 310 can generate commands that correspond to such sampling.

According to an illustration, the periodicity of the UL transmissions sent by the periodic transmitter UL 308 from the access terminal 302 can be connected with the command transmission cycle TPC DL used by the periodic broker 310 to the access terminal 302; therefore, access terminals with different UL transmission intervals can be sent TPC DL commands with different transmission cycles. In addition, the frequency of UL transmissions can be correlated with the number of bits allocated for power adjustments in the access terminals obtained by the periodic broker 310 used for a specific access terminal (such as, for example, the access terminal 302, For example, a mapping between the number of bits allocated for correction of uplink power control and a periodic transmission rate of uplink (such as, for example, transmission rate of SRS, transmission rate of PUCCH, ...). Following this example, a 200 Hz uplink periodic transmission rate can be mapped to 1 bit, a 100 Hz rate can be mapped to 1 bit, a 50 Hz rate can be mapped to 2 bits, a rate 25 Hz can be mapped to 2 bits and a rate of 0 Hz can be mapped to x&gt; 2 bits. According to the aforementioned example, the number of bits allocated for power settings at the access terminal becomes greater as the periodic transmission rate of the uplink decreases. At the limit for a periodic uplink transmission rate of 0 Hz (as, for example, no transmission from SRS, PUCCH,...), The power setting can be x&gt; 2 bits, which may be the case for transmissions open-loop with closed-loop adjustments on a stand as needed.

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The periodic broker 319 can send corrections on a periodic basis to substantially all users in the LTE_ACTIVE state associated with base station 202. According to an example, the users to whom the periodic broker 310 sends commands can be grouped based, for example , on GoS requirements, DRX / DTX cycle and offset, and so on. The transmission of power control commands to the user group can be done by the periodic broker 310 in a specific instantiation of the PDCCH, which can be denoted as CPCCH or TPC-PDCCH. According to another illustration, the periodic broker 319 can use signaling within the range for a group of users, in which the group size can be greater than or equal to 1. The overhead associated with the periodic correction can be based on the number of bits that the correction requires and the related control (if any) necessary to transmit the information to the relevant access terminals.

For the transfer of transmission power control (TPC) commands through the PDCCH by the periodic corrector 310, a payload of 32 bits and a CRC of bits can be used. For example, single-bit TPC commands can be used in a 1 msec interval for a PDCCH instant. Thus, 320 users in the LTE_ATIVO state can be supported at 100 Hz using a single PDCCH in each TTI, assuming that the FDD is used. Therefore, single bit corrections can be obtained every 10 msec, which can provide 100 dB corrections. According to another example, 16 two-bit TPC commands can be used in a 1 msec interval. Thus, 320 users in the LTE_ATIVO state can be supported at 50 Hz using a single PDCCH in each TTI, assuming that the FDD is used.

Therefore

29/64 two-bit corrections every 20 msec provide 100 dB corrections.

Now referring to Figure 4, a system 400 is shown that periodically transfers power control commands to access terminals in a wireless communication environment based on LTE. System 400 includes base station 202, which communicates with access terminal 302 (and / or any number of different access terminals (not shown). The base station 202 includes the received power monitor 204 and the UL 206 power adjuster, which also comprises an aperiodic corrector 402. In addition, access terminal 302 includes a UL 304 power manager, which also includes a receiver of aperiodic 404 commands.

Aperiodic corrector 402 can generate a power control command directed to access terminal 302 on a basis as needed. For example, the aperiodic corrector 402 can transmit aperiodically when triggered by a measurement (such as, for example, the measurement of a recognized condition using data from the received power monitor 204, such as, for example, the received power being outside a range). established margin,...). Aperiodic broker 402 can determine that the uplink power level of access terminal 302 deviates from a target at a specific time; thus, aperiodic corrector 402 can send a command to adjust this power level in response. In addition, aperiodic corrector 402 can obtain a single bit correction (such as, for example, plus / minus ± 1 dB,...) And / or a multiple bit correction (such as, for example, ± 1 dB, ± 2 dB, ± 3 dB, ± 4 dB, ...).

The receiver of aperiodic commands 404 can obtain corrections sent by aperiodic corrector 402 (and / or the

30/64 UL 206 power adjuster and / or the corresponding sector in base station 202 in general). For example, the aperiodic command receiver 404 can decipher that a specific correction sent by the corresponding sector at base station 202 is destined for access terminal 302. Furthermore, based on the corrections obtained, the aperiodic command receiver 404 and / or the UL 304 power manager can change the uplink power level used by the 302 access terminal.

The aperiodic corrections of the uplink power levels used by the access terminal 302 and obtained by the aperiodic corrector 402 can be based on triggering. Thus, aperiodic corrections may be associated with greater overhead compared to periodic corrections due to the unicast nature of aperiodic corrections. In addition, according to an example in which aperiodic corrections of several are used can be mapped into one (and in this case, for example, the power correction can be transmitted as part of the DL assignment or UL uplink concession) or a pair PDCCH / PDSCH (and in this case, for example, the power correction can be transmitted by itself or within the band with another data transmission).

Referring to Figure 5, a system 500 is shown that uses preamble-based power control in an LTE-based wireless communication environment. System 500 includes a sector at base station 202 that communicates with an access terminal 302 (and / or any number of distinct access terminals (not shown). As described above, the corresponding sector at base station 202 may include the received power monitor 204 and the power adjuster UL 206, which may also comprise bits, these instantiation corrections from the PDCCH

31/64 the aperiodic corrector 402, and the access terminal 302 may include the UL 304 power manager, which may also comprise the periodic command receiver 404. Although not shown, the possibility is considered that the UL 206 power adjuster includes periodic corrector 310 of Figure 3 in addition to or instead of aperiodic corrector 402, and / access terminal 302 may include a periodic control receiver in addition to or instead of the aperiodic command receiver 404; thus, the possibility that the object claimed is not limited to the following example, which uses the aperiodic corrector 402 and the receiver of aperiodic commands 404, is considered.

In addition, the UL 304 power manager can also include a preamble generator 502, which transmits a power control preamble, via the uplink, to the corresponding sector on base station 202 before transmitting uplink data (such as, for example, before PUSCH / PUCCH transmission), ...).

In addition, the UL 206 power adjuster can evaluate a preamble evaluator 504, which analyzes the received power control preamble in order to correct the power settings used by access terminal 302, and send a power control command, downlink, to access terminal 302. However, the possibility is considered that the preamble generator 502 is included in the access terminal 302, although separate from the UL 304 power manager and / or that the preamble evaluator 504 is included in the corresponding sector at base station 202 , but separate from the UL 206 power adjuster.

Uplink power control can achieve significant variance in the SNR with bursty transmissions. To mitigate such variance, the transmission of

32/64 preambles can allow power control commands to be provided to access terminal 302 prior to uplink data transmission, where uplink data transmission can be initiated or resumed immediately following a transmitted UL grant through the PDCCH. Upon receiving the UL grant, the UL 304 power manager can use open loop power control to set the initial power level for sending an uplink transmission. By using the preamble generator 502, the transient effect associated with open loop power control can be mitigated when sensitive information is to be sent to the uplink via PUCCH or PUSCH.

The preamble generator 502 can transmit a power control preamble via the uplink. The power control preamble can be a one-time SRS transmission. Such transmission of the power control preamble can be programmed by the corresponding sector at base station 202 (and / or on a network) explicitly or implicitly. The power control preamble sent by the preamble generator 502 allows an uplink transmission to span the channel quickly, covering part or all of the system bandwidth (such as, for example, the minimum bandwidth capacity module). access terminal transmission,...). According to an example, two or four hops per TTI can be obtained with the power control preamble. In addition, the power control preamble can allow the first PUCCH or PUSCH transmission after an UL concession received after UL inactivity to be effectively controlled in power by the closed loop.

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According to an example, when access terminal 302 obtains a UL grant while in LTE_ATIVO_CPC (because of data activity in the downlink, for example), the power of an initial transmission to be sent via the uplink, as determined by UL 304 power manager can be based on open loop power control (without using closed loop mechanisms, for example). The initial open-loop configuration may have noise and therefore may be less than optimal for transmission power. However, since the transmission power of the first uplink transmission from access terminal 302 can be corrected, the security of uplink transmissions can be considerably improved.

To solve the preceding problem, the preamble generator 502 sends a power control preamble that precedes the transmission of information from the access terminal 302 to the corresponding sector on the base station 202 (the information can be transmitted on the PUSCH and / or PUCCH , for example). The power control preamble can be communicated at a power level obtained according to open loop power control mechanisms. The preamble evaluator 504 can obtain and review the power control preamble in order to quickly correct the power settings of the access terminal 302, as evidenced by the power control preamble. For example, the preamble evaluator 504 can generate and transmit a power control command (transmission power control command (TPC), for example) to adjust the power level used by the UL 304 power manager of the access terminal 302. The power control command can be a single-bit correction and / or a multi-bit correction. Then the

34/64 UL 304 power manager can implement the power control command obtained from the corresponding sector at base station 202. In addition, access terminal 302 can then send uplink transmissions (PUSCH and / or PUCCH transmissions, for example) at the corrected open loop power level set by the UL 304 power manager in response to receiving the power control command.

The transmission of the power control preamble to the preamble generator 502 can be programmed explicitly or implicitly by the corresponding sector at base station 202 (and / or by a programmer (not shown) at base station 202). According to an example, explicit programming provides the preamble generator 502 with an explicit indication to send the power control preamble via the uplink. After this example, a UL grant (first UL grant, for example) sent from base station 202 (via the PDCCH, for example) can provide programming related data to transmit the power control preamble via the uplink.

Therefore, the UL grant can make the preamble generator 502 sound the channel effectively (such as, for example, two or four hops spanning the system bandwidth in a given TTI, with the power sent through the uplink). Upon receipt of the uplink transmission by the corresponding sector at base station 202 and analysis by the preamble evaluator 504, a power correction is computed and sent to the PDCCH together with a new UL grant (second UL grant, for example) for the transmission of the PUCCH / PUSCH (which has the power corrected, for example).

35/64 LTE_ATIVO_CPC status, recognize a priori

As another example, the implicit programming of the power control preamble can be used. Based on the fact that the access terminal 302 is in the preamble sub generator 502 it is possible that a power control preamble will be sent before regular data transmission (via PUSCH / PUCCH), for example). Therefore, the corresponding sector at base station 202 does not need to send two UL concessions (as is the case with explicit programming of the power control preamble, for example). Instead, an explicitly flagged UL grant can be applied to a next hybrid automatic repeat request (HARQ) cycle, and the modulation and coding (MCS) scheme and / or features for the power control preamble can be predefined and known by both the access terminal 302 and the corresponding sector at base station 202 (as, for example, retained in the memory of access terminal 302 and / or in the corresponding sector at base station 202). Thus, when using implicit programming, the preamble generator 502 can transfer the power control preamble into the predetermined resources rather than explicitly programmed (as is explicit programming, for example).

After the power control preamble is used to correct the UL power configuration, physical access uplink resources can be reallocated to the access terminal 302 (for example, base station 202) and therefore returned to the LTE_ACTIVE state . While in LTE_ATIVO, subsequent transmissions can be based on corrections generated and sent by the aperiodic broker 402 to the access terminal 302 and implemented by the receiver of the

with case resources for the

36/64 of aperiodic 404 commands (and / or by the UL 304 power manager), as described here.

Now referring to Figure 6, a system 600 is shown that groups access terminals to send power control commands through a downlink. System 600 includes the corresponding sector at base station 202 that communicates with an access terminal 1 602, an access terminal 2 604,. . ., and an access terminal N 606, where N can be any integer. Each access terminal 602-606 can also include a respective UL power manager (such as, for example, access terminal 1 602 includes a UL 1 608 power manager, access terminal 2 604 includes a UL 2 power manager 610, ..., access terminal N 606 includes a UL N 612 power manager). In addition, the corresponding sector at base station 202 may comprise a received power monitor 204, the UL 206 power adjuster and a cluster of access terminals (ATs) 614, which combines a subset of access terminals 602-606 in a group to transmit power control commands via the downlink.

AT grouper 614 can group access terminals 602-606 as a function of several factors. For example, AT group 614 can assign one or more access terminals 602-606 to a group based on a one-phase DRX cycle. According to another example, AT group 614 can allocate an access terminal or terminals 602-606 to groups based on periodic uplink transmission rates (such as SRS transmission rate, PUCCH transmission rate ,. ) used by access terminals 602-606. By combining subsets of 602-606 access terminals into separate groups, the transmission of control commands

37/64 power via the UL 206 power adjuster on the DL via the PDCCH (or CPCCH, TPC-PDCCH) can be performed more effectively (for example, by sending power control commands to various terminals of access grouped together in a common message). Ά example title, the AT group 614 forms groups for use with periodic uplink power control; however, the object claimed is not so limited.

According to an example, the access terminal 1 602 can use a transmission rate of 200 Hz for transmission of the SRS, the access terminal 2 604 can use a transmission rate of 50 Hz for transmission of the SRS and the access terminal N 606 can use a transmission rate of 100 Hz for transmission of the SRS. The AT group 614 can recognize these respective transmission rates (as, for example, using signals obtained by means of the received power monitor 204, ...). Thereafter, the ATs grouper 614 may assign access terminal 1 602 and access terminal N 606 to a group A (along with any other access terminal (s) that use fees 100 Hz or 200 Hz transmission range). ATs grouper 614 may also allocate access terminal 2 604 (and any (any) distinct access terminal (s) that use 25 Hz or 50 Hz transmission rates) to a group B. It should be understood however, that the object claimed is not limited to the aforementioned example. In addition, AT group 614 can assign group IDs to each of the groups (for use in the PDCCH or CPCCH). When assigning access terminals 602-606 to respective groups, the commands sent by the UL 206 power adjuster can use downlink features that correspond to

38/64 a specific group associated with a desired recipient access terminal. For example, AT group 614 and UL 206 power adjuster can work together to send TPC commands to multiple access terminals 602-606 on each PDCCH transmission. Furthermore, each UL 608-612 power manager can recognize transmission (s) to be listened to in order for the PDCCH to obtain appropriate TPC command (s) directed to it (such as example, based on corresponding group IDs, ...).

With reference to transmission structures

Figure 7 shows examples for communicating power control commands to groups of access terminals. For example, transmission structures can be used in PDCCH transmissions. Two exemplary transmission structures are shown (the transmission structure 700 and the transmission structure 702, for example); however, the possibility that the object claimed is not limited to these examples is considered. Transmission frames 700 and 702 can reduce overhead by grouping power control commands for multiple users on each transmission of the PDCCH. As shown, transmission structure 700 groups power control commands for users in group A when a first PDCCH transmission and power control commands for users in group B when a second PDCCH transmission. In addition, both the first and the second transmission of the PDCCH include a cyclic redundancy check (CRC). In addition, the 702 transmission structure combines power control commands for users in groups A and B when using a common PDCCH transmission. As an example, for the transmission structure 702 control commands

39/64 power for users in group A can be included in a first segment of the common transmission of the PDCCH, and power control commands for users in group B can be included in a second segment of the common transmission of the PDCCH.

Referring to Figure 8, an exemplary timing diagram 800 is shown for a periodic uplink power control procedure for LTE. In 802, power control procedures for an access terminal in the LTE_ACTIVE state are shown. In this state, the access terminal sends periodic SRS transmissions to a base station, and the base station responds to periodic SRS transmissions with periodic TPC commands. As shown in the example shown, the transmission power of the access terminal is corrected by a single TPC bit transmitted periodically in the downlink. It should be noted that periodic transmissions from SRS can be replaced by periodic transmissions from CQI, and the like. The transmissions

<td>transmissions</td><td>periodic</td><td>of</td><td>PUCCH</td>

<td>transmissions</td><td>periodic</td><td>of</td><td>CQI</td>

<td>periodic</td><td>PUCCH can</td><td>to be</td><td>any less</td>

<td colspan="2">audible view of the channel, a</td><td>turn</td><td>what are you</td>

not cover the entire system band; however, such transmissions can be triggered for closed loop corrections based on UL measurements at the base station.

In 804, a period of inactivity is shown for the access terminal. After the period of inactivity (predetermined or use of a limit period, for example), the access terminal transitions to the LTE_ATIVO_CPC sub-state. In this sub-state, UL PHY resources are deallocated from the access terminal; therefore, it may not be possible to use closed loop power control when UL transmissions are resumed.

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In 806, the access terminal resumes uplink transmissions. RACH is used to resume uplink transmissions using an open-loop estimate. According to an example, the open loop estimate can be modified according to a last transmission power with some negligible factor if considered beneficial. In response to the RACH sent by the access terminal, the base station can transmit an in-band power setting to the access terminal (such as an x-bit power setting, where x can be substantially any integer) .

In 808, the identity of the access terminal can be verified using the RACH procedure. In addition, reallocation of UL PHY resources can be performed (along with the SRS configuration, for example) at 808.

In 810, the access terminal is in the LTE_ATIVO state. Therefore, the terminal periodic transmissions from the SRS.

periodicity of periodic transmissions from SRS in 810 differ from periodicity of periodic transmissions from SRS in 802; however, the object claimed is not so limited. In response to the SRS periodic transmissions, the base station sends TPC commands that, in this case, account for 2 bits (± 1 dB, ± 2 dB, for example). In addition, although not shown, transmissions from the access terminal may continue to use open loop corrections determined from the reception power level at the access terminal. Therefore, closed-loop corrections can be exclusive and / or on top of open-loop corrections determined from changes in reception power at the access terminal.

Now with reference to Figure 9, an exemplary timing diagram 900 is shown for an access procedure resumes the As shown, the

41/64 aperiodic uplink power control for LTE. Power control procedures for an access terminal in the LTE_ACTIVE state are shown. The timing diagram may lack 900 periodic uplink transmissions. In addition, power corrections can be sent from a base station to the access terminal based on the power received through the PUSCH. The base station evaluates PUSCH transmissions to determine whether to make a power adjustment. Aperiodic power adjustments can be counted on in the event that the base station sends a message (TPC command in the UL concession, for example) to the access terminal if a power adjustment is considered necessary by the base station by evaluating a transmission specific PUSCH. When the base station determines that such a power adjustment is not needed at a specific time for a given PUSCH transmission, the base station does not need to transmit a TPC command at that time in response to the given PUSCH transmission (instead, for example , an ACK can be transmitted in response to the given PUSCH transmission,...). Furthermore, regardless of whether or not a TPC command is obtained by the access terminal at any given time, the access terminal can constantly rely on corrections based on an open-loop mechanism. In addition, corrections sent by the base station can be single-bit and / or multiple-bit corrections.

It should be understood that a similar scheme can be used with periodic UL transmissions in case corrections can be submitted to the DL on an as needed basis. Thus, the access terminal can periodically send SRS transmissions on the uplink, which can be evaluated by the base station in order to determine the power adjustments to be made. In

42/64 then, when determining that a power adjustment is required at a specific time, the base station can send a TPC command, via the downlink, to the access terminal (such as, for example, the aperiodic downlink transmission of commands control system).

The uplink power control procedures shown in Figures 8 and 9 include common aspects. Namely, the notion of ~ PSD (Delta Power Spectral Density) used in UL data transmissions can be used in both periodic and aperiodic uplink power control. ~ PSD can have a maximum transmission power that is allowed for a given user in order to minimize the impact on adjacent cells. ~ PSD can evolve over time as, for example, a function of the charge indicator of adjacent cells, channel conditions, and so on. In addition, ~ PSD can be reported to the access terminal (in-band, for example) when possible. In LTE systems, the network can choose which MCS / Max pilot data power ratio the access terminal is authorized to transmit. The initial ~ PSD, however, can be based on the MSC contained in the UL grant (for example, the relationship between the UL grant and the initial ~ PSD can be based on a formula). In addition, much of what has been said above refers to intra-cellular power control. Other mechanisms for inter-cellular power control (load control, for example) can be complementary to the mechanisms described here.

According to another example, periodic and aperiodic uplink power control procedures can work in combination. Following this example, updates may be periodic

43/64 used at the top of periodic updates. If PUSCH transmissions are programmed, they may require corresponding PDCCH transmissions with the UL grant and, therefore, power control commands can be transmitted on the PDCCHs with UL grants. If the PDCCH is not available, for example, for persistent UL transmissions (for example, which do not require UL grants because PHY resources are configured by higher layers), then the power control commands can be transmitted on the TPC -PDDCHl. In addition, if PDSCH is programmed in the DL, then PUCCH power control (CQI and ACK / NAK, for example) may become more critical. In such a case, the power control commands for the PUCCH can be communicated on the PDCCHs with the DL assignments. For DL ​​transmissions without related control or for the absence of DL data activity, periodic transmissions on the TPC-DPCCH2 can be used to control the power on the PUCCH. Therefore, power control commands can be transmitted when necessary (aperiodically, for example) with the simultaneous use of available resources (such as, for example, PDCCH with UL grants for PUSCH, PDCCH with DL assignments for PUCCH, periodic TPC commands in the TPC-DCCH that may be relevant to PUCCH and PUSCH programmed persistently, ...).

Now with reference to Figure 10, an exemplary timing diagram 1000 is shown for an LTE uplink power control procedure that triggers a power control preamble. Timing diagram 1000 relies on the transmission of a power control preamble programmed from a base station (or network) either explicitly or implicitly. In 1002, a UL grant can be sent from a base station

44/64 (or network) to an access terminal. The UL grant can be transferred through transmission from the PDCCH. In 1004, the access terminal sends a power control (PC) preamble to the base station. The power control preamble can be sent at a determined power level based on an open loop power control mechanism. In 1006, the corresponding sector at the base station can correct the power configuration of the access terminal as collected from the received power control preamble. The corresponding sector at the base station can transmit a power control command (TPC, for example) to the access terminal. The power control command can be a single-bit correction and / or a multi-bit correction. When using explicit programming, the power control command can be sent by the corresponding sector at the base station together with a second UL grant for the access terminal to transmit data. According to another example, when using implicit programming, it is not necessary to send the power control command with an UL grant; instead, the UL grant sent in 1002 can be used by the access terminal to transmit data via the uplink. In 1008, the access terminal can transmit data, through the uplink, to the base station. The data can be transmitted through the access terminal with the corrected power setting (for example, the power level determined by means of open loop power control and adjusted based on the received power control command). For example, data can be sent as a PUSCH transmission and / or a PUCCH transmission. Then, although not shown, the regular closed-loop power control techniques here

45/64 described can then be implemented while the access terminal remains in the LTE_ATIVO state.

Referring to Figures 11-12, methodologies are shown regarding the use of power control preambles in conjunction with uplink power control by means of periodic, aperiodic corrections or a combination of periodic and aperiodic corrections in a communication environment without based on LTE. Although, to simplify the explanation, the methodologies are shown and described as a series of acts, it should be understood that the methodologies are not limited by the order of the acts, since some acts, according to one or more modalities, can occur in orders different from that shown and described here and / or concurrently with other acts. For example, those skilled in the art will understand that a methodology can alternatively be represented as a series of interrelated states or events, as in a state diagram. In addition, it may not be necessary for all acts shown to implement a methodology according to one or more modalities.

Referring to Figure 11, an 1100 methodology is shown that facilitates the generation of a power control preamble for use with power control in a wireless communication environment based on Long Term Evolution (LTE). In 1102, an uplink concession can be received from a corresponding sector at a base station. The uplink grant can be communicated through a Physical Downlink Control Channel (PDCCH) transmission. For example, the uplink lease can be received while an access terminal is in an LTE_ATIVO_CPC state. According to another example, the uplink grant received in 1102 can be a first uplink grant obtained after inactivity on the uplink. In

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1104, a power control preamble can be transmitted to the corresponding sector at the base station with a power configuration based on open loop power control. The power control preamble can be an uplink transmission that quickly sounds the channel through part or all of the system bandwidth (such as modulating the minimum transmission bandwidth capacity of the access terminal) . For example, the power control preamble can be a one-time transmission of the Reference Sound Signal (SRS). In another example, the power control preamble can be an aperiodic Channel Quality Indicator (CQI) report on an uplink data channel. The power control preamble can use two or four hops that span the system's bandwidth over a given transmission time interval (TTI). In addition, the power control preamble can be an uplink transmission that precedes the transmission of uplink data on a Physical Uplink Shared Channel (PUSCH) and / or a Physical Uplink Control Channel (PUCCH). Furthermore, the power configuration used in the transmission of the power control preamble can be based on an open loop power control since the closed loop power control may be unavailable to the access terminal before it is in an LTE_ACTIVE state. Furthermore, the programming of the transmission of the power control preamble can be explicit or implicit. According to an example in which explicit programming is used (transmission characteristics can be explicitly indicated, for example), the uplink grant received in 1102 can allocate resources, specify the modulation and / or the encoding to be used and so on. onwards to

47/64 transmission of the power control preamble. According to another example, in which implicit programming is used (transmission characteristics can be implicitly indicated), resources, modulation, coding, etc. predetermined can be triggered to transmit the power control preamble; like this; the access terminal can use these resources, modulation, coding, etc. predetermined to send the power control preamble through the uplink, without such information being explicitly included in the uplink concession received in 1102.

In 1106, a power control command can be received from the corresponding sector at the base station. The power control command can adjust the power setting of the access terminal used in the uplink transmission. For example, the power control command can be a single-bit correction and / or a multi-bit correction. Thus, the access terminal can modify the configured power according to the power control command. In addition, after the power control preamble is used to correct the power configuration, the physical uplink resources can be reallocated to the access terminal, and the access terminal can transition to the LTE_ACTIVE state. Furthermore, if explicit programming is used, a second uplink lease can be received together with the power control command, and the second uplink lease can be used to send the next uplink data transmission. Alternatively, if implicit programming is used, it is not necessary for the power control command to be accompanied by a second uplink concession; instead, the uplink grant received in 1102 can be used to send the

48/64 next uplink data transmission (for example, the uplink grant in such a case can be applied to the next hybrid auto-repeat request cycle (HARQ)).

In 1108, data can be transmitted to the base station with the power setting adjusted. The open loop estimate for the power setting can be modified by the correction presented as part of the power control command, and data transmission can be done in this adjusted power setting. Data transmission can be in response to the second uplink grant obtained with the power control command if explicit programming is used or to the uplink grant received in 1102 if implicit programming is used. The data transmission may be a Physical Uplink Shared Channel (PUSCH) transmission and / or a Physical Uplink Control Channel (PUCCH) transmission. According to another example, data transmission may refer to a set of periodic transmissions (for example, SRS transmissions, CQI transmissions, PUCCH transmissions, ...).

In addition, a power control command can be received following data transmission at 1108. The power control command can be sent via the downlink when a trigger condition occurs. The power control command can be a single-bit command and / or a multi-bit command. In addition, the power control command can be obtained through a Physical Downlink Control Channel (PDCCH) or a PDCCH / PDSCH (Shared Physical Downlink Channel) pair. In addition, the power control command can be received as an independent transmission or within the band with other data transmitted from a sector

49/64 on a base station. The power setting used for data transmission in 1108 can then be changed based on the power control command. In addition, when a power control command is not obtained, it is not necessary to make such changes to the power configuration. According to another example, whether or not the power control command is received and used to adjust the power setting, open loop power control mechanisms can be used to change the power setting. As another example, data can be transmitted in the uplink to the power setting changed by any type of power control command, such as, for example, periodic and / or aperiodic.

Now referring to Figure 12, a 1200 methodology is shown that facilitates the evaluation of power control preambles for use with power control in a wireless communication environment based on Long Term Evolution (LTE). In 1202, an uplink lease can be transmitted to an access terminal. The uplink grant can be sent while the access terminal is in an LTE_ATIVO_CPC state. Furthermore, the uplink grant can be sent through a PDCCH. According to an example, the uplink grant can explicitly program the transfer of a power control preamble from the access terminal (the transmission characteristics can be explicitly indicated, for example); thus, after this example, the access terminal can assign resources, modulation, coding and the like to be used in the transmission of the power control preamble. As another example, resource, modulation, coding, etc. can be used by the

50/64 access for transmission of the power control preamble (such as, for example, implicit programming, transmission characteristics can be implicitly indicated,...), And the uplink grant sent in 1202 is applicable to a data transmission uplink message sent by the access terminal associated with a next hybrid automatic repeat request (HARQ) cycle.

In 1204, a power control preamble can be received. The power control preamble can be sent from the access terminal to a fixed power level based on open loop power control. In addition, the power level used by the access terminal to transfer the power control preamble can be retrieved from the received power control preamble. The power control preamble can be an uplink transmission that quickly sounds the channel through part or all of the system bandwidth (such as modulating the minimum transmission bandwidth capacity of the access terminal) . For example, the power control preamble can use two or four hops that span the system's bandwidth over a given transmission time interval (TTI). For example, the power control preamble can be a one-time transmission of the Reference Sound Signal (SRS). As another example, the power control preamble can be an aperiodic Channel Quality Indicator (CQI) report on an uplink data channel.

In 1206, the power control command can be generated based on an analysis of the power control preamble, in which the power control command can correct the power level of the access terminal. As an example, the power control command

51/64 can be a single bit correction and / or a multiple bit correction in the power level used by the access terminal. In 1208, the power control command can be transmitted to the access terminal. When explicit programming is used, a second uplink lease can be transmitted together with the power control command, and the second uplink lease can be used to send the next uplink data transmission. Alternatively, when implicit programming is used, it is not necessary for the power control command to be accompanied by a second uplink concession; instead, the uplink lease sent in 1202 can be used by the access terminal to send the next uplink data transmission. In addition, after the power control preamble is used to correct the power level, the physical uplink resources can be reallocated to the access terminal, and the access terminal can transition to the LTE_ACTIVE state. In 1210, an uplink data transmission sent from the access terminal at the corrected power level can be received. The data transmission may be a Physical Uplink Shared Channel (PUSCH) transmission and / or a Physical Uplink Control Channel (PUCCH) transmission. According to another example, the data transmission may refer to a set of periodic transmissions (for example, SRS transmissions, CQI transmissions, PUCCH transmissions, ...).

When receiving the uplink data transmission in 1210, it is possible to determine if the power level used by the access terminal will be adjusted when sending the uplink data transmission. According to an example, the power level can be compared to a target and, if the difference exceeds a limit, then a

52/64 adjustment can be triggered; otherwise, if the difference is less than the limit, then it is not necessary to make the adjustment at that time. In addition, a degree of adjustment in the power level of the access terminal can be determined. When it is determined that the power level must be adjusted, an aperiodic power control command can be transmitted to the access terminal in order to change the power level when triggered by a measurement (eg power level measurement) received that is outside an established margin,...). Thus, the aperiodic power control command can be sent on an as-needed basis. The aperiodic power control command can be a single bit correction such as, for example, increasing / decreasing, ± 1 dB,. ..) and / or a multi-bit correction (such as ± 1 dB, ± 2 dB, ± 3 dB, ± 4 dB,...). In addition, the aperiodic power control command can be mapped to an instantiation of a Physical Downlink Control Channel (PDCCH) or a PDCCH / PDSCH (Physical Downlink Shared Channel) pair. Furthermore, the aperiodic power control command can be transmitted independently or within the band with other data transmissions. In addition, for example, the aperiodic power control command can be sent via a unicast transmission.

It should be understood that, according to one or more aspects described here, inferences can be made regarding the use of power control preambles with aperiodic power control. As used here, the term infer or inference generally refers to the process of reasoning about or inferring states of the system, environment and / or user from a set of observations captured through events and / or data. An inference can be used to identify

53/64 one for a specific context or action, or it can generate probability distribution across states, for example. The inference can be probabilistic - that is, the computation of a distribution of probabilities through states of interest based on the consideration of data and events. An inference can also refer to techniques used to compose higher level events from a set of events and / or data. Such inference results in the construction of new events or actions from a set of observed events and / or stored event data, whether or not the events are correlated in close temporal proximity, and whether the events and data originate from one or more event and data sources.

According to an example, one or more of the methods presented above may include making inferences regarding whether to use explicit programming and / or implicit programming of preamble uplink power control transmissions. By way of another example, it can be related to the identification used for uplink transmission of a power control preamble. It should be understood that the preceding examples are of an illustrative nature and are not intended to limit the number of inferences that can be made or the way in which such inferences can be made in conjunction with the various modalities and / or methods described herein.

an inference of resources to be made

Figure 13 shows a 1300 access terminal that facilitates the use of power control preamps with power control in an LTE-based wireless communication system. Access terminal 1300 comprises a receiver 1302, which receives a signal from, for example, a receiving antenna (not shown) and performs typical actions

54/64 (for example, filter, amplify, perform downward conversion, etc.) on the received signal and digitize the conditioned signal in order to obtain samples. The receiver 102 can be an MMSE receiver, for example, and can comprise a demodulator 1304, which can demodulate received symbols and send them to a processor 1306 for channel estimation. The processor 1306 can be a processor dedicated to analyzing information received by the receiver 1302 and / or generating information for transmission by a transmitter 1316, a processor that controls one or more components of the access terminal 1300, and / or a processor that both analyzes the information received by receiver 1302, generates information for transmission by transmitter 1316 when controlling one or more components of access terminal 1300.

The access terminal 1300 can additionally comprise a memory 1308, which is operationally coupled to the processor 1306 and which can store data to be transmitted, data received, identifier (s) assigned to the access terminal 1300, information related to power control commands obtained and any other appropriate information to select whether to implement the power control commands. Memory 1308 can additionally store protocols and / or algorithms associated with the generation of power control preamps for sending via an uplink and / or estimating power levels for transmission based on open loop mechanisms.

It should be understood that the data storage (memory 1308, for example) described herein can be a volatile memory or a non-volatile memory, or it can include both a volatile and a non-volatile memory. As an example and not a limitation, non-volatile memory can include read-only memory (ROM), programmable ROM

55/64 (PROM), electrically programmable ROM (EPROM), electrically erasable PROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM), which acts as an external cache memory. As an example and not a limitation, RAM is obtainable in many forms, such as synchronous RAM, dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM) , Synchronization Link DRAM and Direct Rambus RAM (DRRAM). The memory 1308 of the present systems and methods is intended to comprise, without being limited to, these and any other suitable types of memory.

Receiver 1302 is also operationally coupled to a UL 1310 power manager that controls the power level used by access terminal 1300 for transmission via an uplink. The 1310 power manager can set the uplink power level to transmit data, control signals, and so on, through any type of uplink channel. The 1310 power manager can use open loop mechanisms to select the uplink power level. In addition, the power control commands obtained by the 1302 receiver can be used by the UL 1310 power manager to adjust the uplink power level. In addition, the UL 1310 power manager and / or receiver 1302 can be coupled to a preamble generator 1312 that generates power control preambles for sending via the uplink at a specific power level (determined by the UL 1310 power manager based on the open loop mechanism, for example). The power control preambles generated by the 1312 preamble generator can be sent to quickly sound the uplink channel with an uplink transmission

56/64 that covers the bandwidth of a wireless communication environment. In addition, power control commands can be received from a base station in response to the power control preambles, and power control commands can be used by the UL 1310 power manager to adjust the open loop estimate used in power control preambles. The access terminal 1300 further comprises a modulator 1314 and a transmitter 1316, which transmits the signal to, for example, a base station, another access terminal, etc. While shown to be separate from processor 1306, it should be understood that the UL 1310 power manager, preamble manager 1312 and / or modulator 1314 may be part of processor 1306 or multiple processors (not shown).

Figure 14 shows a 1400 system that facilitates the analysis of power control preambles for use with power control in an LTE-based wireless communication system. The system 1400 comprises a sector in a base station 1402 (for example, access point, eNB, ...) with a receiver 1410, which receives signal (s) from one or more access terminals 1404 through a series of antennas receiver 1406, and a transmitter 1422, which transmits to the access terminal or terminals 1404 via a transmitting antenna 1408. The receiver 1410 can receive information from the receiving antennas 1406 and is operationally a demodulator 1412, which demodulates the received information. Demodulated symbols are analyzed by a processor 1414, which can be similar to the processor described above with reference to Figure 13, and which is coupled to a memory 1416, which stores information related to access terminal identifiers (such as, for example, IDsDeMAC ,...), data to be

57/64 transmitted to or received from access terminal (s) 1404 (or from a separate base station (not shown) (such as power control command (s), uplink concession (s),. .) and / or any other appropriate information related to the execution of the various actions and functions presented here. Processor 1414 is also coupled to a received power monitor 1418, which evaluates the uplink power levels used by access terminal (s) 1404 based on the signals obtained at base station 1402. For example, the received power 1418 can analyze the uplink power level from a PUSCH transmission. According to another example, the received power monitor 1418 can evaluate the uplink power level from a periodic uplink transmission.

The received power monitor 1418 can be operationally coupled to a preamble evaluator 1420, which analyzes a power control preamble obtained by the base station 1402 of the access terminal (s) 1404. The preamble evaluator 1420 also corrects the power level used by an access terminal from which the power control preamble originates. Thus, the preamble evaluator 1420 generates power control commands to be sent to adjust the power level of the access terminal. The preamble evaluator 1420 can furthermore be operationally coupled to a modulator 1422. Modulator 1422 can multiplex power control commands for transmission by a transmitter 1426 through antenna 1408 to access terminal (s) 1404. Although shown as separate from processor 1414, it should be understood that the received power monitor 1418, the preamble evaluator 1420 and / or

58/64 modulator 1422 can be part of processor 1414 or multiple processors (not shown).

Figure 15 shows an exemplary wireless communication system 1500. Wireless communication system 1500 shows a sector on a base station 1510 and an access terminal 1550 for the sake of brevity. However, it should be understood that system 1500 may include more than one base station and / or more than one access terminal, in which additional base stations and / or access terminals may be substantially similar or different from the base station 1510 and the terminal access 1550 copies described below. It should also be understood that the base station 1510 and / or the access terminal 1550 can use the systems (Figures 1-6, 13-15 and 16-17) and / or methods (Figures 11-12) described here to facilitate wireless communication between them.

At the base station 1510, traffic data for various data streams is supplied from a data source 1512 to a transmission data processor (TX) 1514. According to an example, each data stream can be transmitted via a respective antenna. The TX 1514 data processor formats, encodes and merges the traffic data stream based on a specific coding scheme for that data stream, in order to obtain encrypted data.

The encoded data for each data stream can be multiplexed with pilot data using orthogonal frequency division (OFDM) multiplexing techniques. In addition or alternatively, the pilot symbols can be multiplexed by frequency division (FDM), multiplexed by time division (TDM) or multiplexed by code division (CDM). Pilot data is a known data standard that is

59/64 processed in a known manner and can be used in the access terminal 1150 in order to estimate the response to the channel. Pilot and multiplexed encoded data for each data stream can be modulated (mapped in symbols, for example) based on a specific modulation scheme (such as, for example, binary phase shift switching (BPSK), shift switching phase by quadrature (QPSK), M phase shift switching (M-PSK), amplitude modulation by M quadrature (M-QAM), etc.) selected for this data stream, in order to generate modulation symbols . The data rate, encoding and modulation for each data stream can be determined by instructions executed or provided by the 1530 processor.

The modulation symbols for the data streams can be sent to a MIMO TX 1520 processor, which can also process the modulation symbols (for OFDM, for example). The MIMO TX 1520 processor then sends N_T modulation symbol currents to N_T transmitters (TMTR) 1522a to 1522t. In several modalities, the MIMO TX 1520 processor applies beamforming weights to the symbols of the data streams and to the antenna from which the symbol is being transmitted.

Each transmitter 1522 receives and processes a respective chain of symbols in order to obtain one or more analog signals and also conditions (amplifies, filters and performs upward conversion, for example) the analog signals in order to obtain a modulated signal suitable for transmission through the MIMO channel. In addition, N_T Modulated signals from transmitters 1522a to 1522t are transmitted from N_T antennas 1524a to 1524t, respectively.

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At the access terminal 1550, the modulated signals transmitted are received by N_R antennas 1552a to 1552re, and the signal received from each antenna 1552 is sent to a respective receiver (RCVR) 1554a to 1554r. Each receiver 1554 conditions (filters, amplifies and performs downward conversion, for example) a respective signal, digitizes the conditioned signal to obtain samples and also processes the samples in order to obtain a corresponding received symbol stream.

An RX 1560 data processor can receive and process N_R symbol chains received from N_R1554 receivers based on a specific receiver processor technique to obtain N_T chains of symbols detected. The RX 1560 data processor can demodulate, deinterleave and decode each detected symbol stream in order to retrieve traffic data for the data stream. Processing by the RX 1560 data processor is complementary to that performed by the MIMO TX 1520 processor and the TX data processor on the base station 1510.

A 1510 processor can periodically determine which technology to use, as discussed above. In addition, the 1570 processor can formulate a reverse link message comprising a matrix index part and a classification value part.

The reverse link message can comprise different types of information regarding the communication link and / or the received data stream. The reverse link message can be processed by a TX 1538 data processor, which also receives traffic data for various data streams from a 1536 data source, modulated by a 1580 modulator, conditioned by the

61/64 transmitters 1554a to base station 1510.

At

1554r and transmitted back to base station 1510, the modulated signals from access terminal 1550 are received by antennas 1524, conditioned by receivers 1522, demodulated by a demodulator 1540 and processed by a data processor RX 1542 to extract the transmitted reverse link message access terminal 1550. In addition, processor 1530 can process the extracted message in order to determine which pre-coding matrix to use to determine the beam formation weights.

Processors 1530 and 1570 can guide (for example, control, coordinate, manage, etc.) the operation on base station 1510 and access terminal 1550, respectively. The respective processors 1530 and 1570 can be associated with memories 1532 and 1572, which store program codes and data. Processors 1530 and 1570 can also perform computations to derive frequency and pulse response estimates for the uplink and downlink, respectively.

It should be understood that the modalities described here can be implemented in hardware, software, firmware, middleware, microcode or any combination of them. For a hardware implementation, processing units can be implemented within one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), logic devices (PLDs) , programmable port arrangements on processors, microprocessors, field programmable (FPGAs), microcontrollers, electronics designed to perform described or a combination of them.

controllers, other units the functions here

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When the modalities are implemented in software, firmware, middleware or microcode, program code or code segments, they can be stored in a machine-readable medium, such as a storage component. A code segment can represent a procedure, a function, a sub-program, a program, a routine, a subroutine, a module, a software package, a class or any combination of instructions, data structures or statements of program. A code segment can be coupled to another code segment or a hardware circuit by passing and / or receiving information, data, arguments, parameters or memory contents. Information, arguments, parameters, data, etc., can be passed, sent or transmitted using any device that includes memory sharing, message passing, token passing, network transmission, etc.

For a software implementation, the techniques described here can be implemented with modules (such as, for example, procedures, functions and so on) that perform the functions described here. Software codes can be stored in memory units and executed by processors. The memory unit can be implemented inside the processor or outside the processor, in which case it can be communicatively coupled to the processor by several devices, as is known in the art.

Referring to Figure 16, a 1600 system is shown that allows obtaining power control commands based on power control preambles for use by access terminals in a wireless communication environment. For example, the 1600 system can reside, at least partially, within a sector in a

63/64 a

Beyond symbol. It should be understood that the 1600 system is represented as including function blocks, which can be function blocks that represent functions implemented by a processor, software or a combination of them (a firmware, for example). The 1600 system includes a logical grouping 1602 of electrical components that can act together. For example, logical grouping 1602 may include an electrical component for sending, uplinking via a downlink 1604.

In addition, logic cluster 1602 may include an electrical component to obtain a power control preamble sent at the power level determined from open-loop power estimate 1606. Furthermore, logical cluster 1602 may comprise an electrical component for send a power control command that corrects power level 1608. 0 logical grouping 1602 may also include an electrical component for obtaining uplink data transmission at the corrected power level 1610. In addition, system 1600 may include memory 1612, which retains instructions for performing functions associated with electrical components 1604, 1606, 1608 and

1610. Although shown to be external to memory 1612, it should be understood that one or more of the electrical components 1604, 1606, 1608 and 1610 may exist within memory 1612.

t30

Referring to Figure 17, a 1700 system is shown that allows the use of power control preambles in a wireless communication environment. The 1700 system can reside within an access terminal, for example. As shown, the 1700 system includes function blocks that can represent functions implemented by a processor, software or a combination of them (firmware, for example). The 1700 system includes a

64/64 1702 logical grouping of electrical components that can act together. Logical array 1702 may include an electrical component to obtain an uplink lease 1704. In addition, logical array 1702 may include an electrical component to obtain a power control preamble that alters the power level 1708. Logical cluster 1702 may include an electrical component to transmit uplink data at the changed power level 1710. In addition, the 1700 system may include a 1712 memory, which retains instructions for performing functions associated with electrical components 1704, 1706, 1708 and 1710. While shown as being external to 1712 memory, it should be understood that electrical components 1704, 1706, 1708 and 1710 can exist within memory 1712.

What has been described above includes examples of one or more embodiments. Of course, it is not possible to describe every conceivable combination of components or methodologies for the purpose of describing the aforementioned modalities, but those skilled in the art may recognize that many other combinations and exchanges of different modalities are possible. Therefore, the modalities described are intended to cover all changes, modifications and variations that fall within the spirit and scope of the attached claims. Furthermore, insofar as the term includes is used either in the detailed description or in the claims, it is intended to be inclusive in a way similar to the term which comprises (m) as which comprises (m) is interpreted when used as a word transition in a claim.