KR100855532B1 - Apparatus, system, and method for managing reverse link communication - Google Patents

Abstract

In accordance with an exemplary embodiment of the present invention, an apparatus, system, and method allow a mobile station to choose between transmitting a payload at a standard power level and transmitting a smaller payload at a boosted power level, Manage reverse link resources efficiently. Thus, the mobile station can automatically select the QoS (Quality of Service) level for the physical layer packet. Based on the reverse link transmission information received from the base station, the mobile station derives reverse link transmission guidelines that define at least the relevant payload and power levels for the standard service and the boosted service. The mobile station selects a reverse link transmit power level from a plurality of power levels including at least a standard reverse link transmit power level associated with a standard payload size and a boosted reverse link transmit power level associated with a boosted payload size, the standard payload The size is larger than the boosted payload size.

Reverse link communication, Qos level, communication link resource, mobile station, base station

Description

APPARATUS, SYSTEM, AND METHOD FOR MANAGING REVERSE LINK COMMUNICATION}

1 is a block diagram of a communication system in accordance with an exemplary embodiment of the present invention.

2 shows a table representing example reverse link transmission guidelines, in which reverse link transmission power level and payload size are represented by alphanumeric variables.

3 shows a table showing exemplary reverse link transmission guidelines established using a boost value received from a base station.

FIG. 4 shows a table showing reverse link transmission guidelines including example values, in which payload size is indicated in bits and transmit power levels are represented in traffic to pilot ratios (TPRs).

5 is a flow chart of a method of reverse link resource management performed in a mobile station in accordance with an exemplary embodiment of the present invention.

6 is a flow chart of a method of reverse link resource management performed at a base station in accordance with an exemplary embodiment of the present invention.

TECHNICAL FIELD The present invention generally relates to communication systems, and more particularly, to apparatus, systems, and methods for managing reverse link resources in a communication system.

Many wireless communication systems employ geographically distributed base stations to provide a communication cell or region so that the serving base station provides communication services to mobile stations in the area corresponding to the serving base station. In certain circumstances, reverse link signals transmitted from each mobile station to a base station interfere with other reverse link signals transmitted from other mobile stations. Because of interference and limited resources, the capacity of each base station is limited and many systems manage reverse link resources to improve the overall performance of the communication system. One method of controlling reverse link resources includes limiting the transmit energy of a mobile station. Some conventional systems include a retransmission mechanism that allows information to be correctly reconstructed and received at the base station. By limiting the transmit power level to a relatively low power level, reverse link resources are effectively utilized, while retransmissions allow accurate reconstruction of the transmitted information. Since the retransmission scheme terminates early when good channels are used, the retransmission scheme results in an increase in system capacity for time-varying channels. However, in conventional systems, retransmission causes an increase in transmission delay on the reverse link channel. Resource management techniques in conventional systems allow the mobile station to transmit reverse link signals at relatively high transmit power levels with larger payload sizes. However, for relatively smaller payloads, the mobile station is required to transmit at a lower relative power level, resulting in approximately the same average delay time for all payload sizes.

Accordingly, there is a need for an apparatus, system, and method for efficiently managing reverse link resources of a communication system based on delay considerations.

SUMMARY OF THE INVENTION The present invention is provided to solve the above problem, wherein the apparatus, system, and method select one of the mobile station transmitting the payload at the standard power level and transmitting the smaller payload at the boosted power level. It aims to efficiently manage reverse link resources by allowing them to do so.

In accordance with an exemplary embodiment of the present invention, an apparatus, system, and method are provided by allowing a mobile station to select one of transmitting a payload at a standard power level and ones transmitting a smaller payload at a boosted power level. It effectively manages reverse link resources. As a result, the mobile station can automatically select a Quality of Service (QoS) level for the individual packet based on the delay requirement of the individual packet. Based on the reverse link transmission information received from the base station, the mobile station derives reverse link transmission guidelines that define the relevant payload and power level for at least the standard service and the boosted service. The mobile station selects one reverse link transmit power level from a plurality of power levels including at least a standard reverse link transmit power level associated with a standard payload size and a boosted reverse link transmit power level associated with a boosted payload size; The standard payload size is larger than the boosted payload size.

In an exemplary embodiment, the reverse link signal is transmitted in accordance with a hybrid automatic repeat response (HARQ) protocol. In order to use reverse link resources efficiently, the reverse link transmit power level is maintained at a level that results in multiple re-transmissions, successfully transmitting the payload of most reverse link signals. Since the retransmission scheme terminates early when a good channel is used, the retransmission scheme results in an increase in system capacity for time-varying channels. Payloads transmitted with reverse link signals transmitted at relatively higher transmit power levels experience fewer retransmissions, resulting in lower latency on average than payloads transmitted at lower transmit power levels. Experience. Selecting a specific power level for transmission of the payload affects the number of retransmissions required to achieve the desired frame error, thereby providing a mechanism to control the tradeoff between packet delay and system capacity. In a distributed system using reverse link (or uplink) transmission, the centralized scheduling entity at the base station will not be aware of the delay requirements of future reverse link packets to be transmitted from the mobile station. Based on the available reverse link resources and mobile station general reverse link transmission requirements, the base station assigns an authorized transmit power level. Depending on the authorized limitation, the mobile station chooses between transmitting a smaller payload with a lower delay and transmitting a larger payload with a higher delay. Thus, based on the QoS level of the preferred packet established between the mobile station and the base station or the QoS level of the service, the mobile station automatically selects an acceptable combination of payload size and reverse link transmission power level. In an exemplary embodiment, the reverse link transmit power level is in terms of traffic to pilot power ratio (TPR), where the power control mechanism maintains the power of the pilot signal at a desired level at the receiver for sufficient channel estimation. Are characterized, defined and managed. Thus, TPR provides a scale factor that determines the actual transmit power of the traffic channel. Those skilled in the art recognize that various different techniques may be used to define and characterize the transmit power level in some circumstances. In addition, two or more levels of service may be provided in some environments.

In an exemplary embodiment, the QoS indicator transmitted from the mobile station to the base station via the associated control channel indicates the selected QoS level of the transmission packet. Based on the QoS indicator, the base station determines the TPR used by the mobile station, resulting in improved reception performance.

One or more illustrative embodiments described herein are described in the context of a digital wireless data communication system. Use in such an environment is preferred, but other embodiments of the invention may be included in other environments or configurations. In general, the system described above may be formed using a software-controlled processor, an integrated circuit, or discrete logic. The data, instructions, instructions, information, signals, symbols, and chips that may be referenced throughout this application are preferably voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or these By the combination of. In addition, the blocks shown in each block diagram may represent hardware or may represent method steps or functions.

More specifically, various embodiments of the present invention may be included in a wireless communication system operating in accordance with code division multiple access (CDMA) techniques disclosed and described in various standards issued by the Telecommunications Industry Association (TIA) and other standards bodies. It may be. Such standards include the TIA / EIA-95 standard, the TIA / EIA-IS-2000 standard, the IMT-2000 standard, the UMTS and WCDMA standards, and all standards incorporated herein by reference. The system for communication of data is also described in detail in the " TIA / EIA / IS-856 cdma2000 high rate packet data air interface specification ", which is incorporated herein by reference. Copies of these standards may be obtained by accessing the World Wide Web, or by the TIA, Standards and Technology Department, 2500 Wilson Boulevard, Arlington, Virginia 22201, TIA, Standards and Technology Department, 2500 Wilson Boulevard, Arlington, VA 22201, United States of America) can be obtained by writing a letter. Standards generally identified as UMTS standards, incorporated herein by reference, include 3 GPP Support, 650 Route de Lucio-Sophia Antipoli, Valbonne-France (3 GPP Support Office, 650 Route des Lucioles-Sophia Antipolis, Valbonne- France).

In addition, one or more embodiments of the present invention are applicable to an orthogonal frequency division multiple access (OFDMA) system. The performance of an OFDMA system on the reverse-link is limited by the interference received from the mobile station of the neighboring cell, and the base station or centralized entity must ensure that the mobile station does not transmit at a power level greater than necessary. The base station assigns a frequency tone, also referred to as a subcarrier, and a standard payload format to be transmitted in a specific TPR on the reverse link. In the context of DFDMA, TPR refers to the ratio of power on data to power on pilot tones. In an exemplary embodiment, the mobile station transmits a standard payload format corresponding to the assigned TPR or boosted payload at a lower coding rate and / or a lower modulation order, but at a specified TPR on the assigned subcarrier. You can also choose to send the format. The boosted payload format corresponding to the standard payload format is predetermined by both the base station and the mobile station in a one-to-one correspondence. If the control channel is associated with packet transmission on the reverse-link, the mobile station may transmit a QoS indicator. For fully scheduled OFDMA systems, such as 802.16 issued by the Institute of Electrical and Electronics Engineers (IEEE), mobile stations are not assigned a traffic control channel on the reverse-link. In such a case, the base station may perform blind detection by attempting to decode both the standard and boosted payload formats, which are transmitted in the specified TPR. Cyclic redundancy check (CRC) allows the base station receiver to determine whether the decoded payload is correct.

1 is a block diagram of a communication system 100 in accordance with an exemplary embodiment of the present invention. In an exemplary embodiment, the communication system 100 may operate in accordance with any wireless communication system standard and may be for communication of sound, data, or both. Exemplary communication system 100 exchanges data and controls information through communication links 106-116 between a plurality of mobile stations 118-122 with a wired network 126, including a public switched telephone and data network. May include base stations 102-104. As discussed in more detail below, mobile stations 118-122 and base stations 102 and 104 include any number of components that facilitate operation within communication system 100.

In some situations, base station 102 may be in communication with another base station 104. Base stations 102-104 and various control nodes (not shown) control various aspects of operation of communication system 100 with respect to backhaul 124 between wired network 126 and base stations 102 and 104. In an exemplary embodiment, the backhaul 124 includes equipment and infrastructure that facilitates the exchange of data and other information between the wired network 126 and the base stations 102 and 104 and includes at least one base station controller (BSC); 128).

Each base station 102 and 104 communicates with mobile stations 118-122 within the coverage area of a particular base station via forward link signals 106-108 and reverse link signals 110-116. The forward link signals targeted for the mobile stations 118-120 are accumulated to form the forward link signal 106. In the example situation shown in FIG. 1, one base station 102 communicates with mobile stations 118-122 using one forward link signal 106, and the other base station 104 has another forward link signal 108. Communicates with mobile station 122 using " The forward link may carry a number of different forward link channels, such as control channels. The control channel may be shared between the mobile stations 118-122 receiving the control information. Mobile stations 118-122 communicate with base stations 102-104 using the corresponding reverse link signals 110, 112, and 114 transmitted from mobile stations 118-122 to base stations 102-104. The reverse link signal 114 that is targeted for one base station 104 may be received and decoded at another base station 102. Since mobile stations 118-122 may move from one location to another, and channel conditions may change, mobile stations 118-122 maintain an active set of base stations that may be used for communication in accordance with known techniques.

As described herein, mobile station 118 may include any combination of hardware, software, and firmware that performs functions at mobile stations 118-122, and in an exemplary embodiment, transceiver 136, Controller 138, and memory 140. The functions and operations of the mobile station block shown in FIG. 1 may be implemented in any number of devices, circuits, or software. Two or more functional blocks may be integrated into a single device, and the functions described as being performed in any single device or block may be implemented in some devices. For example, any receiving or transmitting process may be performed by the controller 138.

Mobile station 118 includes a radio transceiver 136 that is configured to communicate with base stations 102-104 in accordance with the protocol of a particular communication system 100. In this example embodiment the transceiver 136 includes a transmitter and a receiver. Radio frequency signals are exchanged through one or more antennas 142. The radio transceiver 138 modulates, amplifies, and transmits the reverse link signal on the reverse link, and receives and demodulates the forward link signal 106 transmitted by the base station 102 on the forward link.

The controller 138 facilitates the overall functionality of the mobile station 118 as well as any processor, microprocessor, computer, microcomputer or combination of processors suitable for performing the control and computational functions of the mobile station 118 described herein. to be. The software code running on the controller 138 executes the steps of the method to process the signal and perform the reverse link management function of the exemplary embodiment.

Memory 140 is any memory suitable for storing values, parameters, software code, and other information in accordance with known techniques. For example, memory 140 may be implemented within an integrated circuit (IC).

Base station 102 may include any combination of hardware, software, and firmware that performs functions for base stations 102-104. The functions and operations of the blocks shown in FIG. 1 may be implemented in any number of devices, circuits, or software. Two or more functional blocks may be integrated into a single device, and the functions described as being performed in any single device or block may be implemented in some devices. For example, some receiving processes may be performed by the controller 132.

The base station includes a radio transceiver 130 that is configured to communicate with mobile stations 118-122 in accordance with the protocol of a particular communication system 100. The transceiver 130 includes a receiver and a transmitter. Radio frequency signals are exchanged via antenna 144, which may include sectors in some circumstances. The radio transceiver 130 modulates, amplifies, and transmits a signal on the forward link, and receives and demodulates a reverse link signal transmitted by the mobile stations 118 through 120 on the reverse link.

The controller 132 facilitates the overall functionality of the base station 102 as well as any processor, microprocessor, computer, microcomputer, or processor suitable for performing the control and computational functions of the base station 102 described herein. It is a combination. Software code running on the controller 132 processes the signals and executes the steps of the method of performing the reverse link management function of the exemplary embodiment.

Memory 134 is any memory suitable for storing values, parameters, software code, and other information in accordance with known techniques. For example, the memory 134 may be implemented within an integrated circuit (IC).

Base stations 102-104 transmit control commands to mobile stations 118-122 via forward link signals 106 and 108. The control command may include any number of parameters, values, bits, or other information depending on the particular communication standard used in the communication system 100. In this exemplary embodiment, the control command includes a reverse link control parameter that provides information suitable for determining the reverse link power level (applied TPR) applied to the mobile station 118. Examples of reverse link control parameters include a rate control command and a payload assignment message. The applied reverse link power level (Applied TPR) is the maximum reverse link power allowed by the base station 102 and reverse link transmission for other reverse link transmissions from other mobile stations 120 and 122 to the base station 102. Provides a mechanism to control the interference. In addition to an authorized reverse link power level, such as an authorized traffic to pilot power ratio (authorized TPR), the base station 102 includes information that allows the mobile station 118 to maintain reverse link transmission guidelines. Convey other reverse link transmission information, such as transmission parameters. Any few techniques may be used to convey the reverse link transmission parameters. For example, a presentation of reverse link transmission parameters may be transmitted to mobile station 118. Examples of communication systems that can support such a mechanism include fully scheduled CDMA or OFDMA communication systems. For example, in some circumstances, such as a rate controlled CDMA system, only limited information may be transmitted, such as an indication of a change in reverse link transmission parameters. In addition, the reverse link transmission indicator received at the mobile station 118 may identify a set of parameters stored in the memory 140.

The reverse link transmission guidelines may be maintained using any of several techniques, but in an exemplary embodiment the mobile station 118 associates the traffic to pilot power ratios (TPRs) with the reverse link payload, thereby providing memory 140 Keep the variable value of. As described in more detail below with reference to FIGS. 2-4, the reverse link transmission guidelines relate to power levels such as TPR values for at least two quality of service (QoS) levels. In an exemplary embodiment, the plurality of standard TPR values correspond to payload sizes for standard transmissions, and the plurality of boosted TPR values correspond to payload sizes for boosted transmissions. The boosted TPR value is generally higher than the standard TPR value for the corresponding payload size. Based on the reverse link signal and the payload size of the applied TPR, the mobile station 108 selects either a standard TPR or a boosted TPR for transmitting the reverse link signal. Various criteria may be used to select the TPR, but the mobile station 118 selects the TPR according to the most compatible delay and payload size combination. For example, mobile station 118 may select a standard TPR where the particular payload is a relatively large FTP file and a higher delay can be tolerated. Mobile station 118, on the other hand, may select a boosted TPR in which the payload is short and a lower delay is desired. Low latency is often desirable in real time applications such as video applications.

When selecting the reverse link transmit power level, the mobile station 118 identifies the highest standard power level and the highest boosted power level that meets the requirements of the authorized reverse link transmit power level (AUTH_PWR), and the current page. Consider the load size and latency preferences to estimate the corresponding payload size. In an exemplary embodiment, the highest standard TPR and the highest boosted TPR are associated with the payload and correspond to the TPR used by the mobile station 118 for the quality of service required when transmitting the payload. Thus, the highest standard power level is identified as the standard power level (standard TPR), which corresponds to a payload format that is less than the applied power level. The highest boosted power level is identified as the boosted power level (boost TPR) corresponding to the payload format, which is less than or equal to the sum of the standard power level (standard TPR) and the margin factor (q). The margin factor provides a margin above the highest standard TPR that allows the mobile station 118 to transmit the reverse link signal in boosted mode. Thus, margin provides a mechanism to reduce the effect of quantization when a limited number of payload formats are defined by communication system 100. The selection of the boosted TPR after the standard TPR determination allows the system 100 to maintain a reference point for updating the authorized TPR. Thus, in a communication system using a rate determination process, an algorithm for selecting a standard payload is retained, and the mobile station 118 can transmit the payload at a boosted power level after the rate determination process identifies the standard payload. . In some circumstances, the highest boosted power level is directly identified as the boosted power level corresponding to the payload less than the maximum applied power level.

FIG. 2 shows a table representing exemplary reverse link transmission guidelines 200 in which reverse link transmission power levels and payload sizes are represented by alphanumeric variables. Reverse link transmission guidelines 200 define the relationship between allowable transmit power levels 204 and 208 and a plurality of payload sizes 202 and 206 for at least two QoS (Quality of Service) classes. As described below, the reverse link transmission guidelines 200 are in terms of traffic to pilot ratios (TPRs) for standard service and boosted service for some reverse link transmission power levels 204, 208 of the exemplary embodiment. Transmit power levels 204 and 208 are defined. "Payload" refers to a certain number of bits of information, coded and modulated according to some known format, and transmitted on a traffic channel, such as a packet data channel (PDCH). The payload may be defined by any combination of payload, code rate, modulation order, or parameters indicating multiple bits of the CRC. However, any number of transmit power levels 204 and 208 and payload sizes 202 and 206 may be defined as any of several formats, ratios, and units, depending on the implementation of the particular communication system 100. May be The table of FIG. 2 includes a set of standard payload sizes 202 and a set of boosted payload sizes 206. In an exemplary embodiment, a single set of payload sizes is associated with a set of standard power levels 204 and a set of boosted power levels 208, with each payload size associated with a standard power level and a boosted power level. do. In an exemplary embodiment, each standard power level value is less than the corresponding boosted power level value for the same payload size. Although the exemplary reverse link transmission guidelines 200 are shown as a table, the guidelines 200 may be implemented and implemented in any of several ways, and the relationship between the various values need not necessarily be maintained as an array in memory. none.

As mentioned above, the mobile station 118 maintains an authorized reverse link transmission power level (AUTH_PWR) that may be transmitted, modulated, updated, or otherwise established by the base station 102. The mobile station 118 is below the authorized reverse link transmission power level and meets the requirements defined by the reverse link transmission guidelines 200 and the reverse link transmission powers 204 and 208 for the payload sizes 202 and 206. Is applied to transmit the reverse link signal at any power level. In a system using orthogonal reverse link transmission, the reverse link signal utilizes the subcarrier assigned to the mobile station in the OFDMA system and the assigned code space as the associated data rate.

Those skilled in the art will recognize various suitable techniques for conveying reverse link transmission information to the mobile station 118 based on the teachings herein and known techniques. As discussed above, the base station 102 transmits control information over the forward link that includes reverse link transmission information suitable for maintaining reverse link transmission guidelines 200. In addition to the values stored at the mobile station 118, any combination of indicators, adjustment indicators, and transmitted values may be used to generate the reverse link transmission guidelines 200. For example, whenever guideline 200 changes or occurs, values indicative of reverse link transmission parameters are transmitted directly from base station 102 to mobile station 118. In some circumstances, only changed values may be transmitted. In other situations, the information transmitted from the base station 102 may only include a difference value in order to relate the boosted power level to the standard power level for the same payload size. In an exemplary embodiment, the single set of payload sizes 202 and 206 are fixed and not adjusted by the information transmitted by the base station. In addition, the reverse link transmission guidelines 200 are defined by an initial value prior to the application of the reverse link transmission parameters received from the base station.

One example technique for establishing reverse link transmission guidelines 200 is to establish a set of payload sizes and standard power levels in accordance with known techniques and to boost transmit power levels (boosted from reverse link parameters received from base station 102). 205). 3 shows a table representing exemplary reverse link transmission guidelines 200 established using a boost value, D, received from base station 102. The boost value, D, indicates the difference between the standard transmit power level 204 and the boosted transmit power level 208 for the corresponding payload size 302. For example, looking at the variables in the third column of the table of FIG. 3, the power level S3 corresponds to the payload size P3. The boosted power level 208 for payload size P3 is equal to the sum of S3 and D (S3 + D). In addition to the reverse link parameters required to establish the guidelines 200, the base station 102 transmits other reverse link transmission information that allows the mobile station 118 to determine an appropriate transmit power level for the reverse link signal. Examples of additional reverse link information include a power margin q indicating a margin above the highest standard power level below the authorized power level that the mobile station 118 can transmit in boosted mode. In this embodiment q and D are constant, but in some circumstances the values of q and D vary between various payload sizes.

Other methods of generating boosted power level 208 may include other parameters that provide a proper relationship between payload size and power levels 204 and 208. For example, in some situations, the reverse link parameters may include a payload reduction value, R, indicating a decrease in payload size from the standard payload size to the boosted payload size corresponding to the particular power level. .

Any some techniques may be used to establish and maintain reverse link transmission guidelines 200. Two exemplary techniques are provided directly below. In the first exemplary technique, mobile station 118 maintains a variable, AUTH_PWR, indicating a reverse link transmission power level applied by base station 102. Base station 102 may establish and change AUTH_PWR by any combination of grant message and rate control transmission. Based on AUTH_PWR, mobile station 118 uses guidelines 200 to determine the payload format applied for the standard mode. A suitable method of determining the payload format includes determining the largest payload corresponding to a standard power level that is less than or equal to AUTH_PWR. For example, if AUTH_PWR is greater than S3 but less than S4 (S3 <AUTH_PWR <S4), mobile station 118 identifies P3 as the maximum allowable standard payload size.

Two examples of selecting a boosted payload size are described directly below. In a first example, the mobile station 118 calculates the boosted power level and the corresponding payload size based on the payload size P3, the boost parameter D, and the standard power level S3 corresponding to the margin q. A suitable method of determining the boosted payload format includes determining the largest payload corresponding to the boosted power level that is less than or equal to S3 + q. For example, if S3 + q is greater than the boosted power level S2 + D but less than S3 + D (S2 + D <S3 + q <S3 + D), then the mobile station selects P2 as the maximum allowable boosted payload size. Identifies as.

In the second technique, the highest boosted payload format is determined directly from AUTH_PWR. If S2 + D <AUTH_PWR <S3 + D, then P2 is selected as the maximum allowable boosted payload size. Mobile station 118 selects a boosted power level or a standard power level based on the delay requirements and payload of the reverse link signal. The first technique implements the second in a scenario where the mobile station chooses to transmit in boosted mode but transmits a payload size P1 lower than the maximum allowable boosted payload size P2 due to other constraints such as power and data constraints. Preferred over form. In the first technique, there is a one-to-one mapping between the selected standard payload format and the boosted payload format. If the mobile station 118 chooses to transmit to P1 instead of P2 when it is boosted, the base station 102 derives the corresponding standard payload format and updates AUTH_PWR based on the standard payload power level. can do. In the second technique, different boosted payload formats (eg, P2 and P3) may be selected, while the same standard payload format P3 may be selected for different values of AUTH_PWR. The variable AUTH_PWR used by mobile station 118 may not be known to base station 102. In this situation, transmitting either P2 or P3 in the boosted mode will result in greater ambiguity at the base station 102 when determining the AUTH_PWR of the mobile station 118.

In a second technique, the mobile station 118 establishes a transmission guideline 200 and corresponds to the largest payload size corresponding to the maximum standard power level equal to or less than AUTH_PWR, and the maximum payload corresponding to the maximum boosted power level equal to or less than AUTH_PWR. Determine the size. Based on the delay requirements and the payload of the reverse link signal, the mobile station 118 selects one of the maximum boosted power level and the maximum standard power level. In a second technique, a margin factor q may be added to AUTH_PWR to determine the maximum boosted power level (ie, the maximum boosted power level <AUTH_PWR + q).

4 shows guidelines 200 including exemplary values, where payload size 302 is represented by information bits, and transmit power levels 204 and 208 are represented as traffic to pilot ratios (TPRs). The city of the table. Two examples are discussed with reference to FIG. 4, which shows two example techniques that use reverse link transmission guidelines to determine a suitable power level and payload size combination for a reverse link signal.

In the example of the first technique, AUTH_PWR is equal to 12,2 dB, D is equal to 2 dB, and q is equal to 0.5 dB. Thus, the payload corresponding to the maximum standard TPR is 1560 bits because the corresponding 10.1 dB standard TPR is less than 12.2 dB applied TPR but larger than the next highest 12.6 standard TPR. Adding 0.5 dB to the highest standard TPR yields 10.6. Thus, the largest boosted TPR is 9.3 dB, which is the sum of 7.3 dB and 2.0 dB. Mobile station 118 selects one of transmitting 792 bits of payload at 9.3 dB in boosted mode and transmitting 1560 bits of payload at 10.1 dB.

In the example of the second technique, AUTH_PWR is 12.2 dB, D is equal to 2 dB, and q is not used. After the mobile station 118 generates or otherwise establishes the reverse link transmission guidelines 200 using the parameters, the payload corresponding to the maximum standard TPR and the maximum boosted TPR is determined. Since 10.1 dB (corresponding to 1560 bits) <12.2 dB <12.6 dB (corresponding to 3096 bits), the maximum standard TPR is 10.1 with an associated payload size of 1560. Since 12.1 dB (corresponding to 1560 bits) <12.2 dB <14.6 dB (corresponding to 3096 bits), the largest boosted TPR is 10.1 dB. Thus, the payload size for the boosted mode is 1560 bits. Mobile station 118 selects one of transmitting a payload of 1560 bits at 12.2 dB in boosted mode and transmitting a payload of 1560 bits at 10.1 dB.

In order to manage reverse link resources efficiently, the base station 102 uses rate control algorithms and signaling in this exemplary embodiment. Rate control may be achieved by an acknowledgment message, a rate control indicator (RCI), or any combination of the two. An example of a suitable technique for rate control will be described below, filed on May 25, 2004, and entitled “Reverse Link Data Rate Control of Mobile Station with Reverse Link Common Rate Control in a Communication System”. (METHOD AND APPARATUS FOR CONTROLLING REVERSE LINK DATA RATE OF A MOBILE STATION IN A COMMUNICATION SYSTEM WITH REVERSE LINK COMMON RATE CONTROL). The acknowledgment message is sent to the mobile station 118 to indicate the authorized TPR, and the RCI provides information to adjust the TPR. The RCI includes RATE_DOWN, RATE_HOLD, and RATE_UP indicators. In order to facilitate rate control in this exemplary embodiment, a service indicator (QoS indicator) is sent from the mobile station 118 to the base station 102 to indicate the type of service used to transmit the payload. . A suitable mechanism for transmitting a QoS indicator in a communication system operating in accordance with the CDMA Revision D standard includes transmitting one bit indicator over a reverse packet data control channel (R-PDCCH). As is known, the R-PDCCH carries information corresponding to the packet format over the Reverse Packet Data Channel (R-PDCH). One bit indicator indicates whether the transmitted reverse link signal 110 is being transmitted with a standard service (or standard Qos) and a boosted service (or boosted QoS).

5 is a flow chart of a method of reverse link resource management performed in a mobile station 118 in accordance with an exemplary embodiment of the present invention. This method may be performed by hardware, software, and firmware, alone or in combination. The example method described with reference to FIG. 5 is performed at a mobile station 118 having a functional block that includes at least a controller 138 and a memory 134. As described above, the functional blocks identified by mobile station 118 may be implemented using any combination of components, processor, and software code, and may be implemented in a single device or distributed to several components or devices.

In step 502, the reverse link applied power level (AUTH_PWR) is established at the mobile station 118. In an exemplary embodiment, base station 102 transmits a combination of grant and rate control messages to maintain an authorized reverse link transmit power level value (AUTH_PWR). According to the rate control method, the base station 102 may periodically adjust AUTH_PWR by sending RCIs to the mobile station 118.

In step 504, the reverse link transmission information is received from the base station 102. The reverse link transmission information includes information, values, parameters, or other indicators suitable for establishing the reverse link transmission guidelines 200 at the mobile station 118. In an exemplary embodiment, the reverse link information includes at least information for establishing a standard TPR value in accordance with known techniques, as well as information allowing determination of the boosted TPR value. Examples of suitable reverse link parameters include boost value, D, margin factor, q, maximum number of sub-packets for standard transmission, maximum number of sub-packets for boosted transmission size for boosted mode transmission, and TPR. In some circumstances, other parameters may be transmitted, such as a payload reduction factor, R, indicating a reduction in the number of payload sizes required for the boosted transmission.

In step 506, reverse link transmission guidelines 200 are established based at least on a portion of the reverse link information. In an exemplary embodiment, the standard payload size is stored in memory and is associated with a boosted transmit power level value generated based on the received reverse link transmission information and the standard power level value. Suitable methods of establishing the guideline 200 include the two example techniques described above with reference to FIGS. 3 and 4. Other methods and techniques may be used in some situations.

In step 508, the mobile station selects a reverse link transmit power level from a plurality of power levels including at least a maximum boosted power level and a maximum standard transmit power level compatible with an applied reverse link transmit power level. In an exemplary embodiment, the mobile station 118 determines the delay requirement of the packet to be transmitted and estimates the payload size associated with the power level values for the standard mode and the boosted mode. Based on the QoS of the particular packet required, mobile station 118 selects one of the payload and power level combinations for the standard and boosted modes.

6 is a flow chart of a method of reverse link resource management performed at base station 102 in accordance with an exemplary embodiment of the present invention. This method may be performed by hardware, software, and firmware, alone or in combination. The example method described with reference to FIG. 6 is performed at a base station 102 having a functional block comprising at least a controller 132, a transceiver 130, and a memory 134. As noted above, the functional blocks identified at base station 102 may be implemented using any combination of components, processor, and software code, and may be implemented in a single device or distributed to several components or devices.

In step 602, the base station delivers the reverse link transmit power level applied to the mobile station 118. The base station sends any number of grant messages and rate control indicators (RCIs) to maintain the appropriate value of AUTH_PWR, as maintained at base station 118.

In step 604, the base station transmits reverse link transmission information that establishes reverse link transmission guidelines 200 at the mobile station 118. Reverse link transmission guidelines 200 allow mobile station 118 to select a reverse link transmission power level without requiring additional authorization from base station 102. As mentioned above, the mobile station selects one of a boosted power level and a standard power level.

Thus, in this example embodiment, the mobile station 118 can choose between transmitting the payload at the standard power level and transmitting the smaller payload at the boosted power level. The base station 102 establishes reverse link transmission guidelines by transmitting reverse link information to the mobile station 118. Using the guidelines 200, the applied power reverse link power level, and the QoS requirements of the reverse link packet, the mobile station 118 does not require authorization from the base station 102, and the appropriate power level for the reverse link packet; Select a payload size combination. Thus, the reverse link level and payload are managed to efficiently allocate reverse link resources.

Clearly, other embodiments and variations of the present invention will be apparent to those skilled in the art in view of the description of the division. The above description is illustrative only and not restrictive. The invention is not limited to the following claims, including all such embodiments and modifications, when viewed with reference to the foregoing detailed description and the accompanying drawings. Therefore, the scope of the present invention is not to be determined by the foregoing detailed description, but rather by the appended claims and their equivalents.

As described above, according to the apparatus, system, and method according to the present invention, by allowing a mobile station to select one of transmitting a payload at a standard power level and transmitting a smaller payload at a boosted power level. Therefore, it is possible to efficiently manage reverse link resources.

Claims (9)

A method of managing communication link resources from a mobile station to a base station in a communication system, comprising: Selecting a payload size of a data packet for transmission over the communication link; Receiving a boost transmit power value from a base station for transmitting the data packet over the communication link, the boost transmit power value indicating an amount of power level difference between a boosted power level and a standard power level; Selecting one of the boosted power level or the standard power level based on a delay requirement of the data packet transmission; And transmit the data from the mobile station to the base station over the communication link at the payload size and the selected power level. The method of claim 1, Correlating the selected power level with a traffic to pilot power ratio such that the boosted power level is a boosted traffic to pilot power ratio and the standard power level is a standard traffic to pilot power ratio. Resource management method. The method of claim 1, And wherein said delay requirement of said data packet transmission is in accordance with a hybrid automatic repeat response protocol. The method of claim 1, Transmitting the boost transmit power value from the base station. The method of claim 1, Receiving at the base station the data packet transmitted from the mobile station over the communication link at the payload size and the selected power level. An apparatus for managing communication link resources from a mobile station to a base station in a communication system, comprising: A controller for selecting a payload size of a data packet for transmission over the communication link; A transceiver for receiving from the base station a boost transmit power value for the transmission of the data packet over the communication link indicating an amount of power level difference between a boosted power level and a standard power level; A controller for selecting either the boosted power level or the standard power level based on a delay requirement of the data packet transmission; And a transceiver for transmitting the data from the mobile station to the base station via the communication link at the payload size and the selected power level. The method of claim 6, The controller further includes associating the selected power level with a traffic to pilot power ratio such that the boosted power level is a boosted traffic to pilot power ratio and the standard power level is a standard traffic to pilot power ratio. And a communication link resource management device. The method of claim 6, And wherein the controller is further configured to cause the delay requirement of the data packet transmission to comply with a hybrid automatic repeat response protocol. The method of claim 6, Transmit the boost transmit power value, And a controller and a transceiver in the base station configured to receive the transmitted data packet from the mobile station over the communication link at the payload size and the selected power level.

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