RU2345508C2 - Method and device for return data transmission rate control - Google Patents

Abstract

FIELD: physics, communication.

SUBSTANCE: invention refers to communication engineering and aims at evaluation of data transmission rate for return communication line. Data bursts to be transmitted to number of communication service, while data transmission rates are evaluated for data burst transmission, relying on data burst queue position, thus making it possible to respond transmission term for each data burst. Base station detects whether available resources enable allocation in base station to transmit from mobile station at specified data transmission rate and time. Mobile station transmits at least data burst from queued data bursts to determine new data burst queue. New data burst queue is used to evaluate new data transmission rate for return communication.

EFFECT: selection of return data transmission rate in communication.

30 cl, 7 dwg

Description

Priority claim by 35 U.S.C.§35

This patent application claims the priority of provisional patent application No. 60/448269, entitled “Reverse Link Data Communication”, filed February 18, 2003, and provisional patent application No. 60/469376, entitled “Method and Apparatus for Controlling Data Rate of Reverse Link in a Communication System ”, filed May 9, 2003, the rights to which belong to the copyright holder of this patent application, and which are incorporated into this description in its entirety by reference.

FIELD OF THE INVENTION

The present invention relates generally to the field of data exchange, and more particularly to controlling the data rate of the reverse link from a mobile station to a communication system.

Disclosure of invention

In a wireless communication system, excessive and excessive user transmissions can interfere with other users in addition to reducing system performance. Excessive and excessive loading can be caused by an ineffective choice of the reverse link data rate in the communication system. Data transferred between two end users can go through several protocol layers to ensure an appropriate data flow through the system. Typically, a mobile station receives data blocks for transmission on a return line from an application. The data block is divided into several frames and transmitted over the communication line. Appropriate data delivery in at least one aspect is provided by using an error checking system in each data frame and requesting retransmission of the same data frame if an unacceptable error or an unacceptable error level is detected in the data frame. The data blocks can be of any type, for example, music data, video data, etc. Data blocks can be of different sizes, have different requirements for delivery. Such delivery requirements are often related to quality of service. Service quality can be measured by the data exchange rate, packet loss rate, which may be acceptable for a given service, compatibility in the time delay of data delivery, and a suitable maximum delay in data exchange. Very often, if the data rate selected for transmission is not appropriate, the requested packet loss parameters and communication delays cannot be achieved.

In the case of direct line data exchange, the base station very often has relevant information about the quality of the direct line with several mobile stations. For example, a base station may be able to centrally control the forward link data rate. However, in the case of a return line, the mobile station does not have transmission information from other mobile stations. Therefore, the mobile station may make a request for transmission permission at a certain data rate. After viewing the requests of each mobile station, the base station accepts or rejects the requested data rate. If the requested data rate is rejected, the mobile station may request a lower rate until the base station receives the requested data rate. A mobile station may have permission to transmit below a data rate without performing a request and receive procedure. This data rate is usually a very low data rate. Before transmitting on the reverse link, the mobile station must complete its data exchange to request a data rate. Such an exchange of service data between mobile stations and base stations may reach an unacceptable level and affect the required quality of service.

Therefore, there is a need to provide a system, method and apparatus for selecting a reverse link data rate in a communication system.

Brief Description of the Drawings

Distinctive features, objects and advantages of the present invention will become more apparent from the detailed description below, taken in conjunction with the drawings, in which like reference numerals indicate corresponding elements.

In FIG. 1 shows a communication system for transmitting and receiving data in accordance with various aspects of the present invention.

In FIG. 2 shows a receiver system for receiving data in accordance with various aspects of the present invention.

In FIG. 3 shows a transmitter system for transmitting data in accordance with various aspects of the present invention.

In FIG. 4 shows a flowchart of messages and processes for determining the data rate for data exchange on the return line.

In FIG. 5 is a message and process flow diagram illustrating resource allocation in response to a data rate request.

In FIG. 6 is a diagram illustrating graphically the calculation of the requested data rate and download speed.

In FIG. 7 is a diagram illustrating alternative coding options for a differential bit rate field with 2-bit coding.

The implementation of the invention

One or more illustrative embodiments set forth herein are described below in the context of a wireless digital data exchange system. Although use in this context is advantageous, various embodiments of the present invention may be included in various environments or configurations. Typically, the various systems discussed herein can be configured using a software-controlled processor, integrated circuits, or discrete logic. The data, instructions, commands, information, signals, symbols and microcircuits referred to in this annex are mainly represented by voltages, currents, electromagnetic, magnetic fields or particles, optical fields or particles, or a combination thereof. Additionally, the blocks shown in each flowchart may represent hardware or method steps.

More specifically, various embodiments of the present invention can be incorporated into a wireless communication system operating according to code division multiple access (CDMA) technology, which is set forth and described in various standards published by the Communications Workers Association (TIA) and other standards organizations. . Such standards include the TIA / EIA-95 standard, the TIA / EIA-IS-2000 standard, the IMT-2000 standard, the UMTS and WCDMA standard, which are incorporated herein by reference in their entireties. The data exchange system is also described in detail in the “TIA / EIA / IS-856 cdma2000 High Rate Packet Data Air Interface Specification”, incorporated herein by reference in its entirety. Copies of the standards can be obtained by contacting: http://www.3gpp2.org or by writing to TIA, Standards and Technology Department, 2500 Wilson Boulevard, Arlington, VA 22201, United States of America. Typically, the standards identified as the UMTS standard, incorporated by reference in its entirety, can be obtained by contacting 3GPP Support Office, 650 Route des Lucioles-Sophia Antipolis, Valbonne-France.

In FIG. 1 shows a general block diagram of a communication system 100 capable of operating in accordance with any standard of a code division multiple access (CDMA) communication system using various embodiments of the present invention. The communication system 100 may be designed to transmit voice, data, or both. Typically, communication system 100 includes a base station 101 that provides communication links between multiple mobile stations, such as mobile stations 102-104, and between mobile stations 102-104 and a public switched network 105. The mobile stations of FIG. 1 can be considered as data access terminals (AT), and base stations as a data access network (AN), without departing from the main scope and various advantages of the present invention. A base station may include several components, for example, a base station controller and a base station transceiver system. For simplicity, these components are not shown. The base station 101 can communicate with other base stations, for example, the base station 160. A mobile switching center (not shown) can control various aspects of the operation of the communication system 100 and the exchange of data via the backhaul 199 between the network 105 and the base stations 101 and 160.

The base station 101 interacts with each mobile station that is in its coverage area through a direct line signal coming from the base station 101. The direct line signals intended for mobile stations 102-104 can be summed to generate a direct line signal 106. A straight line can carry several different channels of a straight line. Each of the mobile stations 102-104 receiving the forward link signal 106 decodes the forward link signal 106 to extract information that is intended for its user. Base station 160 can also communicate with mobile stations that are in its coverage area through a forward link signal coming from base station 160. Mobile stations 102-104 can communicate with base stations 101 and 160 through corresponding return lines. Each return line is supported by a return line signal, for example, reverse line signals 107-109 for mobile stations 102-104, respectively. Signals 107-109, although they may be for one base station, may be received by another base station.

Base stations 101 and 160 can simultaneously exchange information with a common mobile station. For example, a mobile station 102, which can communicate with both base stations 101 and 160, may be in the vicinity of base stations 101 and 160. In the case of a straight line, base station 101 transmits a direct line signal 106 and base station 160 a direct line signal 161 . In the case of a reverse link, the mobile station 102 transmits a reverse link signal 107 for both base stations 101 and 160. To transmit a data packet to the mobile station 102, one of the base stations 101 and 160 may be selected in order to transmit packet data to the mobile station 102 In the case of a return line, both base stations 101 and 160 may attempt to decode the transmission of traffic data from the mobile station 102. The data rate and power level of the forward and reverse links can be maintained in accordance with em channel between the base station and the mobile station, as described in various aspects of the present invention.

In FIG. 2 is a block diagram of a receiver 200 used to process and demodulate a received CDMA signal during operation in accordance with various aspects of the present invention. Receiver 200 may be used to decode information in the forward and reverse link signals. A receiver 200 may be used to decode information in the primary channel, the control channel, and the auxiliary channels. Received samples (Rx) may be stored in RAM 204. Received samples are generated by the radio frequency / intermediate frequency (RF / IF) system 290 and the antenna system 292. The RF / IF system 290 and the antenna system 292 may include one or more components to obtain a plurality of signals and the RF / IF processing of the received signals to exploit diversity gain. Many received signals that have passed through various propagation paths can be generated by a common source. The antenna system 292 receives the RF signals and sends the RF signals to the RF / IF system 290. The RF / IF system 290 may be any conventional RF / IF receiver. Received RF / IF signals are filtered, downconverted, and digitized to form RX samples of the main frequency band. The samples are supplied to a multiplexer (mux) 252. The output signal mux 252 is supplied to a search unit 206 and taps 208. They are connected to the control system 210. An adder 212 connects the decoder 214 to the tap elements 208. The control system 210 may be a microprocessor controlled by software, and may be located on the same integrated circuit or on a separate integrated circuit. The decoding function in decoder 214 may be performed by turbo decoding or any other suitable decoding algorithms. The signal transmitted from the source can be encoded using several levels of coding. Decoder 214 may perform a decoding function according to two or more types of codes. For example, the transmitted data may be encoded at two different layers, the outer layer and the physical layer. The physical layer may correspond to the turbo code, and the outer layer may correspond to the Reed Solomon code. Decoder 214 decodes the received samples according to such codes.

During operation, the received samples are fed to mux 252. Mux 252 feeds the samples to the search unit 206 and tap elements 208. The control unit configures the tap elements 208 to demodulate and compress the received signal at various time offsets based on the search results from the search unit 206. The demodulation results are combined and sent to decoder 214. Decoder 214 decodes the data and provides decoded data. Compression for this channel is performed by multiplying the received samples by the complex conjugation of the PN sequence and the assigned Walsh function for one timing hypothesis and digital filtering of the resulting samples, often using the integration circuit and the accumulating adder circuit (not shown). Such a technology is well known in the art. A receiver 200 can be used in the receiving part of the base stations 101 and 160 for processing received reverse link signals from the mobile stations and in the receiving part of any of the mobile stations for processing the received forward line signals.

Decoder 214 may accumulate total energy to detect a data symbol. Each data packet may carry a control field using a cyclic redundancy code (CRC). The decoder may be coupled to a control system 210 and / or other control systems to detect errors in a received data packet. If the CRC data did not pass the verification, then the received data packet was received with an error. The control system 210 and / or other control systems may send a negative acknowledgment message to the transmitter for retransmission of the data packet.

In FIG. 3 shows a block diagram of a transmitter 300 for transmitting forward and reverse link signals. Channel data for transmission is input to a modulator 301 for modulation. Modulation can be performed in accordance with any well-known modulation technology, for example QAM, PSK or BPSK. Prior to modulation, the channel data for transmission may be encoded at one or more coding layers. Channel data for transmission is generated for modulator 301. Channel data for modulation is input to modulator 301.

The data modulation rate can be selected using the selector 303 data rate and power level. The selection of the data rate may be based on feedback information received from the destination. In addition to other factors taken into account, very often the data rate is selected based on the state of the channel and in accordance with various aspects of the present invention. Channel status may change over time. The choice of data rate may also change over time.

Thus, the data rate and power level selector 303 selects the data rate in the modulator 301. The output of the modulator 301 undergoes a signal expansion procedure and is amplified in block 302 for transmission through the antenna 304. The data rate and power level selector 303 also selects the power level for the gain level of the transmitted signal. The combination of the selected data rate and power level provides the ability to correctly decode the transmitted data at the receiving point. At block 307, a pilot signal is also generated. At block 307, the pilot signal is amplified to an appropriate level. The power level of the pilot signal may correspond to the state of the channel at the receiving point. The pilot signal may be combined with the channel signal in adder 308. The combined signal may be amplified in amplifier 309 and transmitted through antenna 304. Antenna 304 may be any number of combinations, including antenna arrays and configurations with multiple inputs and multiple outputs.

In the CDMA 2000 system, a mobile station (MS) is allowed to use several communication services at the same time. Each of these communication services may differ in quality of service (QoS). For some services, data packets may be associated with specially defined QoS parameters, such as a specific data rate or range of data rates, packet loss rate, and the maximum delay allowed for exchanging a data packet or multiple data packets. During the negotiation phase of the link service, the MS and the base station (BS) agree on a set of QoS parameters. QoS parameters can be determined for the duration of a particular communication service. Then, the BS may be required to support with high probability such consistent QoS, for example, data rate, packet loss, and maximum delay.

According to various aspects of the present invention, a method and apparatus are provided for implementing reverse link QoS in which updated information regarding queue length and maximum packet delay is available in the MS, although the resource manager assigning the agreed QoS is in the BS. The MS requests the necessary transmission speed from the BS, and does not report information on the length (number of packets not transmitted) of the queue. The MS calculates the requested data rate and the data validity period until the BS requests the data rate. The data rate request may be in the form of one or more ratios of forward link traffic channel power to pilot power (T / P). The set of available data rates may have corresponding T / P ratios. A table may be provided to reflect the correspondence between T / P and data rate. Autonomous control of the data rate by means of the MS can also be based on feedback from the BS download. The BS may be responsible for assigning speed to the MS to control download and reverse link stability. The BS is also responsible for access control. The allocation of resources in response to a request for a data rate may be shown in the diagram of the message flow and processes shown in FIG.

The real resources controlled by the BS are the ratio of the traffic channel power to the pilot power (T / P). The mapping of the data rate in T / P for a channel is an operating point that is selected based on the number of valid retransmissions and the use of hybrid ARQ. The BS may designate different types of mappings as a function of the delay requested (valid retransmissions) for each service. This optimization is useful for services with short transactions and very low latency requirements (for example, interactive games). For most services, the best choice for a BS is to choose a mapping in which the reverse link throughput is maximized. The numbers (1-8) on the left side represent the possible order of events or processes that may take place.

1. The BS controls access authorization and allows only communication services (or streams) with valid and achievable QoS requirements. After allowing a service or data packet stream, the MS is aware of the agreed QoS parameters, such as allowable data rate, packet loss rate, and maximum delay associated with the specified stream. It should be noted that due to channel changes and mobility, such QoS guarantees are sufficiently probable.

2. The MS implements a policy (upstream) that discards incoming data packets that do not meet the requirements. Thus, the MS accepts all packets for which the implementation of the policy assumes the satisfaction of the agreed QoS for allowed flows. Packets that require QoS beyond the agreed QoS, as determined, for example, by the data rate, are discarded to the MS until the output queue formation stage. The MS can also implement an external control loop mechanism for matching control parameters based on operating conditions. The BS can “verify” that the MS really matches the speed agreed with it.

3. Satisfying packets allowed in the MS are placed in the output queue. Each package has a due date based on the delivery time of the package and the maximum allowable delay for this service (or stream). Preferably, the MS can set the output queue so that the packets are stored in the order of their maximum delays, the first having the closest execution time. The MS should manage the planning of its transmission to ensure that packets will be transmitted before their expiration date.

4. The MS determines the requested data rate based on the deadlines associated with the packets in the output queue. The procedure is described more fully below. Since the data rate determined by the MS is required to provide consistent QoS, the requested data rate is not only a sign of “priority”. The MS also calculates one or more data download speeds by determining which packets in its queue can be skipped in order to enable the BS to assign speeds lower than the requested speed if the requested speed cannot be assigned by the base station due to loading, congestion of the control channel or any other reason. The download speed is determined by the MS based on the requested speed and the number of packets that can be skipped in the queue. Usually, if a packet in the queue is skipped, then the data rate requested to transmit the remaining number of packets increases. The BS converts the requested download speed and download speed to the requested T / P and T / P download, or as an alternative, the MS can directly calculate the requested T / P and T / P download.

5. The MS reports the requested T / P and T / P load or increase or decrease T / P and transmits it to the BS. The BS should try to satisfy the requirements for increasing T / P in the presence of available resources, since such resources are necessary for the MS to satisfy its QoS criterion. Several consecutive requirements for increasing T / P from the MS indicate an increase in priority, and in case of failure, this may lead to the failure of some QoS criterion.

6. The BS scheduler complements these T / P requirements in terms of reverse link resources and time. The BS also does not account for some resources with known low latency, constant bandwidth streams, such as voice calls. The BS may try to optimize such an arrangement, for example, by delaying some T / P destinations or by providing higher T / P destinations with a shorter duration. If the BS delays the assignment for the MS, subsequent requirements from the MS may require an even higher T / P to satisfy QoS for delay-sensitive packets, since with a larger delay in transmitting a data packet, the higher data rate required for the same QoS is required for transmission. Thus, the BS has limited flexibility in planning. In the presence of excess bandwidth resources, the BS may not take into account T / P reduction requirements or provide T / Ps higher than those requested.

7. The BS designates the T / P for the MS. The destination may be indicated for the MS in the form of an increase (decrease) in the current assigned data rate.

8. Based on the destination of the T / P, the MS composes the packets for transmission. The MS serves the packages based on the “first - with an earlier deadline” layout order and can modify it. For example, before the start of the transmission of any packet, the MS determines whether there is a transmission of this data packet within its execution time. Such a definition is a function of the assigned T / P and deadlines and should be calculated with the possibility of future increase. MS passes any packet for which it is probably not possible to maintain the deadline for the transmission. A package that is not successfully transferred before its expiration date is considered lost. The MS monitors the packet loss rate associated with the stream.

In such an infrastructure, the processes of steps 2, 3, and 8, respectively, allow the MS to control the QoS (speed, maximum delay and packet loss requirements) associated with its flows. The processes of steps 4 and 5 allow the MS to combine its requirements for all its flows into one T / P requirement. The BS access control process in step 1 ensures that the BS will have a sufficient amount of resources in step 6 to satisfy the requirements of all access flows from the MS with an agreed QoS. The MS determines the requested data rate to satisfy QoS. The MS combines the queues for multiple services (with consistent QoS) into a speed requirement. Moreover, usually instead of determining the requested speed and converting to the requested T / P, the MS can work directly with the requested T / P. This is a more general case, since it is easy to adapt the transmission of packets for various services with different types of T / P conversion to speed.

Suppose that at time t _{0, the} MS queues consist of packets P _i , {i = 1, ..., N} of size s _i , organized in order of their due date d _i . Each packet P _i is associated with a data service k (i). For the data service k, the mapping of the known data rate in T / P is defined as R _k (T / P). Then, for the assigned T / P value of T ₀ , the following equations can also be determined. At a speed of R _{k (i)} (T ₀ ), the transmission time of the packet P _i over the communication line, x _i , has the form:

x _i = s _i / R _{k (i)} (T ₀ ) (1)

Since the packages are placed in order of their deadlines, the package P _i will be completely transferred for

z _i = t ₀ + Σs _j / R _{k (j)} (T ₀ ), where the summation is performed according to [1, ..., i] (2)

That is, packets P ₁ , ..., P _i-1 with execution dates of up to d _i are transmitted before P _i . Thus, the process can determine if any packet in the output queue of the MS can skip its deadline, i.e.

z _i > d _i , for 1≤i≤N (3)

If the MS determines that any packet in its queue may miss its due date at the current speed, then it may request a higher speed to satisfy its QoS. It should be noted: this calculation of the data transfer rate uses the information about the deadlines associated with each packet in the queue of the MS. The BS cannot make such a determination of the data rate based on the number of packets not transmitted and the QoS class.

There are several ways to provide the requested T / P information in a BS. Depending on the implementation of the request channel and the frequency of transmission of requests from the MS to the BS, it may also be useful to calculate the requested duration in the MS and provide this feature in the BS. Equation 2 above also allows the MS to determine the desired duration. Essentially, at the assigned T ₀ value of the T / P ratio, the transmission of the last packet in the MS queue can be completed in time z _N. Therefore, based on the current packet queue and the assigned rate, the required duration is z _N. Equation 2 can be modified using small additional calculations. For example, if at the next moment of time t ₁ when the transfer of the packet P _{1 is completed, the} assigned T / P is changed to T ₁ , the changed times of the completion of packet transmission are expressed as:

z _i (t ₁ ) = t ₁ + Σs _j / R _{k (j)} (T ₁ ), where the summation is performed according to [2, ..., i] (4)

Such completion times can be calculated from the previous packet transfer completion time using the equation:

z _i (t ₁ ) -t ₁ = z _i (t ₀ ) -t ₀ -s ₁ / R _{k (1)} (T ₀ ) + Σs _j [1 / R _{k (j)} (T ₁ ) -1 / R _{k (j)} (T ₀ )], (5)

Then suppose that a new package P _{new of} size s _new , service k (new), and due date d _new arrives at time t ₂ . Typically, the deadline for a new package is between the (ordered) deadlines for packages k and k + 1, i.e. for some k <N, d _k ≤d _new <d _{k + 1} . Then for i≤k zi (t2) is unchanged. If the T ₁ value for T / P does not change,

z _i (t ₂ ) = z _i (t ₁ ) + s _new / R _{k (new)} (T ₁ ) for i> k (6)

Thus, the MS can calculate and update its requested T / P, the requested duration, as well as the planned packet transmission order in its queue.

To assist the BS in speed assignments during load periods, the MS also calculates download speeds by determining which packets in its queue may be skipped. To determine the priority of packet passing MS can use many criteria:

Packages for services that are tolerant of packet skipping,

Packages for services whose current packet loss rates are less than the agreed packet loss rates,

Packets for which it is likely that the maximum delay requirement will not be met if the requested T / P is not assigned.

Based on the priority of skipping, the MS determines which packets can potentially be skipped, while satisfying acceptable QoS at various load levels. Then, the MS uses equations (1) - (3) to form a virtual queue by removing such packets from the MS queue to calculate the T / P load value. It should be noted that in all respects, the data packet and the data block may be interchangeable.

If the mapping of T / P to speed is fixed, then working with the data transfer rate is more suitable and adequate. A diagram that illustrates graphically the calculation of the requested speed and data download speed is given below. Package sizes and lead times are also shown graphically. The size of each packet (in bits) is shown as a vertical bar placed on its execution time along the time axis (in frames). The size of the vertical bar indicates the size of the packet. Any line with a positive slope at the origin corresponds to the speed (bit / s). The origin is the current time or the start time of the assignment. The requested speed has the smallest slope that satisfies all deadlines, i.e. the smallest slope at which all packets on the chart are located below the line. The MS also calculates the download speed based on the assumption that the first packet in the queue can be skipped (download level 1) and the download speed if the largest packet in the queue is skipped (download level 2).

At time t _{0, the} MS queue consists of packets P _i , {i = 1, ..., N} of size s ₀ placed in the order of their due date d _i . Then, for the assigned speed R _0, you can write the following equations. At a speed of R ₀ , the transmission time x _i of the packet P _i over the air is

x _i = s _i / R ₀ (7)

Since the packages are placed in order of their expiration date, the Pi packet transfer will end in

z _i = t ₀ + z _j + s _j / R ₀ , where the summation is performed according to [1, ..., i] (8)

That is, packets P ₁ , ..., P _i-1 with a due date of up to d _i are transmitted earlier than P _i . Thus, the process can determine whether any packet in the queue of the MS can skip its due date, i.e.

z _i > d _i , for 1≤i≤N (9)

If the MS determines that any packet in its queue may miss its deadline, then it requests a higher speed to satisfy its QoS. Such a data rate calculation uses the due date information associated with each packet in the queue. The BS cannot make such a speed determination based only on the number of packets not transmitted and the QoS class.

There are several ways to provide information about the requested speed in the BS. Depending on the implementation of the request channel and the frequency of transmission of requests from the MS to the BS, it may also be useful to calculate the requested duration in the MS and provide this feature in the BS. Equation 2 above also allows the MS to determine the requested duration. In fact, at the assigned speed R _{0, the} last packet in the MS queue can complete its transmission at time z _N. Equation (2) can be modified using very small additional calculations. For example, if at the next time t ₁ at the end of the transmission of the packet P _{1 the} assigned speed has changed to R ₁ , the changed times of the completion of the transmission of the packet are expressed as:

z _i (t ₁ ) = t ₁ + Σs _j / R ₁ (T ₁ ), where the summation is performed according to [2, ..., i] (10)

Such completion times may be calculated from previous completion times using the equation:

z _i (t ₁ ) -t ₁ = [(z _i (t ₀ ) -t ₀ ) R ₀ -s ₁ ] / R ₁ (11)

Further, suppose that a new package P _{new of} size s _new and with a due date d _new arrived at time t ₂ . Typically, the deadline for a new package can be between the (ordered) deadlines for packages k and k + 1, i.e. for some k <N, d _k ≤d _new <d _{k + 1} . Moreover, for i≤kz _i (t ₂ ) is unchanged. If the speed R ₁ does not change,

z _i (t ₂ ) = z _i (t ₁ ) + s _new / R ₁ for i> k (12)

Thus, the MS can calculate and update the required speeds, the required duration, as well as the planned order of transmission of packets in the queue.

As shown above, by estimating the maximum delay of all packets in the MS buffer, the MS can determine the requested speed or T / P. Alternatively, if the MS evaluates only the first packet in its buffer, that is, the packet with the shortest delay execution time, and uses the T / P (or speed) calculations described above, the result is equivalent to the presence of feedback on the maximum delay in the BS. In this case, the calculated T / P (or speed) value represents the shortest lead time and equivalently the highest priority. An example of a two-bit coding of the delay execution time for the reverse link channel is shown in the following paragraphs and can be used.

Reverse link requests can be sent to the BS either through a message or using a continuous low speed rate control channel. The following schemes may be taken into account and used:

- Use of a return line message to provide information on the queue length or the number of packets not transmitted in the BS. To support QoS, a QoS field may be added to such a request message.

- A continuous channel request T / P or speed, in which the MS periodically puts a bit indicating a request for a higher speed. This does not provide the BS with any indication of QoS.

BS managed resources include a ratio of traffic channel power to pilot power (T / P). Typically, a higher T / P ratio is mapped to a higher data rate. The system may use several mapping schemes between the T / P ratio and the corresponding data rate. Typically, the MS always chooses to display the data rate in T / P so as to maximize reverse link throughput. For some services (such as interactive games) with short transactions and very low latency requirements, it may be necessary to work with fewer retransmissions and higher T / P. Thus, if the data packet at the beginning of the queue in the MS has a very short execution time (for example, less than 40 ms), the MS can choose a special speed display in T / P suitable for services with low latencies. There is the possibility of applying the scheme either using speed and displaying it in T / P, or directly calculating the requested T / P.

In order to allow the BS resource manager to determine the priorities of appointments during loading periods, in addition to the requested T / P, the MS also indicates one or more T / P values of the BS load. The BS is trying to accurately assign the requested T / P to all MSs. If the requested resources exceed the available resources, the BS changes the requested T / P for one MS at a time (in some order determined by the BS) with a lower T / P assigned with load level 1, until the general purpose for all mobile stations will not match available resources. If necessary, the BS can go to T / P associated with level 2 of the load. The sign of the requested T / P or data rate and T / P download or download speed may be transmitted via a short control message, a continuous message, or a combination thereof.

In the request message to the BS, the requested T / P and its duration may be provided based on the calculations performed in the MS. Such a request message may not include feedback on the number of unsent packets and QoS for the BS. The BS cannot calculate the requested T / P and its duration based on the number of packets not transmitted and the QoS class. To control QoS (speed, packet loss, maximum delay), periodic messages that request T / P and its duration are preferred for periodic feedback on the number of packets not transmitted and the QoS class. In response, the BS assigns the T / P and duration to the MS through an authorization message. MS continues to change its (local) speed and calculate the duration. A modified request is triggered whenever there is either a significant change in the requested T / P, or the requested duration is significantly greater than the assigned duration. A permit with the assignment of a zero T / P may indicate the expiration of the permit for the MS.

Once T / P is enabled for the MS, a low-speed continuous reverse link request channel can be used to reduce the exchange of overhead information when transmitting request messages. The MS supports the Current Grant variable based on the resolution from the BS. Alternatively, there is the possibility that the resolution is implicit, i.e. any MS is allowed to autonomously set its Current Grant variable to the global (initial) value of Current Grant and, thus, eliminate the need for any messages.

As shown in FIG. 7, based on calculations of the requested rate, the MS continuously sends requests to increase, decrease, or keep its Current Grant unchanged. The T / P increase request also indicates whether an increase is necessary to meet T / P at various load levels. The message may include a differential rate request field with 2-bit encoding. The MS indicates the level of its Current Grant with respect to the requested speed and download speeds, for example, if the Current Grant is between the requested T / P and T / P level 1 load, then the MS request contains the bit code “10”. Alternatively, a differential bit rate field with 2-bit coding may be included, which contains only load level 1 and a new level that prevents buffer underfill for delay-sensitive traffic.

Optionally, a threshold value D _{0 of} leading long-term resolution may also be determined. If the calculated MS required duration exceeds D ₀ , then this may indicate a request for long-term permission. This is useful because it allows the BS to perform forecasting and thus better control the allocation of its resources and planning decisions. For the scheduler, high-speed requests are “priority” requests, while long-term resolution requests indicate the number of packets not transmitted.

Alternatively, two bits may be used at the beginning of the queue to represent the maximum delay (or priority level) of a packet. For example:

Priority level Maximum header delay of the next packet 3 less than x 2 more than X but less than 3X one more than 3X but less than 9X 0 more than 9X (i.e. better option)

X is a system parameter, the value of which may be fixed for a given BS or may be fixed depending on the set of services for a given MS.

The MS transmits the T / P value using the Current Grant on the return line. The BS determines the value of the Current Grant variable in the MS from the current transmission. The BS can determine this value by measuring the ratio of the power of the traffic channel to the power of the pilot signal in the transmission of the MS or by the speed used by the MS to transmit, and then displaying it in T / P.

The BS resource manager uses the current T / P used by this MS, together with the information in the T / P request for a fair distribution of T / P among the MS. For example, depending on the load level, a BS can satisfy only load level 1 requests for all MSs. The BS can then assign a T / P increase for the MS whose request indicates 00 or 01, with a higher priority for MS requests indicating 00. The BS can assign a T / P decrease for the MS whose request indicates 11 or 10. The BS can also use an additional criterion for controlling the distribution of load among MS.

The work of the BS resource manager can be explained by the following example. Consider the case of three MS:

MS 1: Ec_Pilot [1], Current Grant [1], request = 10

MS 2: Ec_Pilot [2], Current Grant [2], request = 01

MS 3: Ec_Pilot [3], Current Grant [3], request = 01

MS 4: Ec_Pilot [4], Current Grant [4], request = 11

MS 5: Ec_Pilot [5], Current Grant [5], request = 00

MS 6: Ec_Pilot [6], Current Grant [6], request = 10

In the above example, all MSs except MS 4 require a higher T / P than the Current Grant to satisfy the requested T / P. MS 4 may be assigned a reduction in its Current Grant. The purpose of the increase may or may not be proposed by another MS depending on the results of additional calculations. The BS resource manager is able to calculate the use of current resources based on the Ec_pilot signal and Current Grant for each MS, as follows.

Resource Use = ΣЕс_Pilot [i] * [Current Grant [i] +1] (13)

BS allows an increase (upward correction) or a decrease (downward correction) relative to the Current Grant. The increase or decrease is a factor for the Current Grant, the value of which Adjust [i] is set as (1 + a) or (1-a), respectively. Once assigned, the modified resource use can be calculated as

Resource Use = ΣЕс_Pilot [i] * [Adjust [i] * Current Grant [i] +1] (14)

The resource manager algorithm may perform the following steps. It ends with the stage where they find the set of adjustment values Adjust [i], in which the use of the changed resources is below the threshold value T _{max of} maximum resource use.

Step 1. Assign a decrease for MS 4 and an increase for all other MS. Adjust [4] = 1-a, Adjust [i] = 1 + a, for i = 1,2,3,5,6. With this purpose, an attempt is made to move all the MSs to satisfy their requested T / Ps. Determine the modified use of resources. If the modified resource use is below the maximum threshold value T _max , such an assignment is allowed and it can be performed. If the resource use exceeds T _max , go to step 2.

Stage 2. There is no possibility of moving all MS in the direction of the requested T / P. More specifically, the process moves all of the MSs in the T / P direction of load level 1. This means that in addition to MS 4, a downward adjustment can be made for MS1 and MS6. That is, Adjust [i] = 1-a for i = 1,4,6 and Adjust [i] = 1 + a for i = 2,3,5. Again, it is determined whether or not the assignment of the changed resources is permissible, i.e. whether there is an excess of the general allowable resource allocation If this is not valid, go to step 3.

Stage 3. There is no possibility of moving all MS in the direction of T / P level 1 load. More specifically, the process moves all of the MSs in the T / P direction of load level 2. This means that all MS, except MS 5, can be assigned a downward adjustment. That is, Adjust [i] = 1-a for i = 1,2,3,4,6 and Adjust [5] = 1 + a. Again, it is determined whether or not the assignment of the changed resources is permissible, i.e. whether there is an excess of the general allowable allocation of resources. If this is not valid, proceed to step 4.

Step 4. The T / R BS adjustment algorithm is not able to determine the purpose that meets the requirements. An explicit message may be required to complete the transfer from one of the MSs. The BS chooses which resolution should be completed based on various criteria, including: “fairness” and the size of the current appointment in the MS.

To indicate corrections in the Current Grant, a continuous low-speed reverse link enable channel may be applied to the MS. The MS modifies its Current Grant variable based on the current permissions (and adjustments) it receives from the BS. Since permits are distributed continuously in the MS, there is no need to specify a long-term permission in the MS. The request for long-term permission (if used) only allows the BS to perform forecasting and thus conduct better planning of decisions.

Encoding in a continuous low-speed reverse link enable channel may be performed as follows:

+1, if the mobile station has received instructions for increasing T / P by a given amount, and may also depend on T / P;

-1 if the mobile station has received instructions to reduce T / P by a given amount, and may also depend on T / P;

0 if the mobile station has received instructions to keep the T / P unchanged.

If the BS does not decode the continuous request channel reliably (for example, a reverse pilot channel (R-PICH) is received with low power and the symbols of the continuous request channel are deleted), the BS sets the forward enable channel symbol to 0. Otherwise, if the continuous request channel reliably decoded, the BS sets the symbol of the forward resolution channel, respectively.

Although the BS resource manager determines the load level based on MS requests, and instead of requiring a continuous permission channel for each MS, with some loss of flexibility, it is possible to use a continuous common resolution channel that only indicates the current calculated load level in the BS (for example, encoded as one of three levels shown above). Based on such an indication, the MS can autonomously adjust its data transfer rate, following the same logic. For example, if the total BS resolution indicates load level 1, the MS requesting 10 should decrease its T / P until the MS requesting 01 can increase its T / P for the next transmission. Moreover, despite the decrease in the volume of overhead data in a straight line, a continuous common resolution channel eliminates the BS’s ability to distinguish between competing MSs, based on additional criteria. There is also the possibility of eliminating the continuous channel of the request and the transition to the autonomous operation of the MS. The indication of loading from the BS is based on current measurements of the use of MS resources, and not on requests from the MS. Thus, a closed control loop in the MS is absent. In this case, the BS is not able to distinguish between MSs for which the QoS requirement is satisfied, and MSs for which the QoS requirement is not satisfied, and therefore is not able to use the principle of “fair distribution”.

Essentially, signaling errors in the continuous request and enable channel are not fatal. It is understood that information distortion in the continuous forward resolution channel is a command to keep the Current Grant unchanged. Thanks to the closed-loop control mechanism with a low delay, any alarm error can be quickly corrected by subsequent requests and permissions. In particular, the local variable Current Grant in the MS becomes known in the BS at each frame transmission on the return line and allows the two sides of the closed control loop to maintain the same state.

It is possible to perform a reverse link QoS control operation only using request and grant messages. However, for tight QoS management, i.e. To control QoS of services with pulsating delivery traffic, variable speeds and strict restrictions on delays, it is necessary to use a continuous channel of requests and permissions. It should be noted that a continuous channel of requests can be used without a continuous channel of permissions.

In the case of a consistent QoS for traffic, the MS can work as follows:

- The MS sends a request message that indicates the requested T / P (and T / P download). The request message may also contain a maximum T / P (operational reserve in the MS). The BS may indicate the T / P resolution through the message, or the resolution may be implicit (known source T / P). In the latter case, neither a request nor permission is required.

- Changes in the requested T / P are indicated in the continuous channel of the speed request with a small amount of service data. The channel must be set up and released using level 3 alarms. Since this channel represents the total speed requirement for the MS, only one such channel is needed for each MS.

- Changes for the allowed T / P are indicated by the base station in a continuous forward link resolution channel with a small amount of overhead. Alternatively, a continuous common resolution channel with a small amount of overhead data can be used, which indicates the level of load based on the received requests.

During the soft handoff operation, the reverse link resource management based on messages is carried out only by the serving BS (the BS with the highest average pilot signal strength obtained from the MS). Continuous channels of requests and permissions can be received and transmitted only by the serving BS or a reduced active set of BSs. If only the serving BS transmits the continuous permission channel, the operation of the soft handoff is not different from the case when the mobile station is not in the soft handoff state. However, if the forward fast grant channel is transmitted from more than one active set BS, the other BS may operate independently and generate different permission commands. The MS then adjusts its Current Grant variables to the minimum speed adjustments allowed by all BSs in the active set.

The amount of overhead information per MS for a continuous channel of requests and permissions is comparable with the use of messages-based channels once every several hundred ms. Thus, to bring the volume of service information into correspondence, requests and speed permissions should be sent no more than, for example, 250 ms for each MS, taking into account all the services for this MS. Continuous feedback channels may be required to control QoS services, in which the maximum delay is less than, for example, 100 ms. Even for services with pulsating delivery, where the queue size can vary significantly in tens of ms. If the maximum delay is greater than 250 ms, then QoS can be controlled through channels based on request and permission messages. Every 20-40 ms, 2-4 bits may be required in the continuous reverse rate request channel. These bits indicate the BS requested modifications at the BS set speeds and / or the need for long-term resolution.

The infrastructure for managing QoS and resources in the return line is disclosed, with packet queues distributed in the MS, and a centralized resource manager located in the BS. In such an infrastructure, the MS is responsible for managing the reverse link QoS, while the BS controls the total resources and access control for services with consistent QoS. The MS provides the requested resource (speed or T / P) with the resource manager, which is necessary to satisfy its QoS. This differs from previous approaches, in which the MS provides information about the number of packets not transmitted in the queue to the resource manager. Information about the number of unsent packets in the queue is not sufficient for the resource manager to provide guaranteed QoS. The reverse link QoS is controlled by the MS through a closed loop control of the assigned speed or T / P. QoS requirements for multiple services (or flows) are combined into a compact representation of the resource (speed or T / P). This allows you to effectively implement (low volumes of exchange of service information) closed loop control. This allows the MS to determine the requested T / P, which will allow it to satisfy the QoS requirements for all services. A simple mechanism is needed to recalculate the speed (or T / P) and duration after sending packets, delivering packets, changes in assigned speeds, or changes in line quality. Continuous channels of requests and permissions with a small amount of overhead information are consistent with the infrastructure and are suitable for managing QoS services with requirements of maximum delay not exceeding 100 ms. A process is disclosed for calculating T / P requirements for various load levels using packet pass priority. A compact encoding of a speed request channel is disclosed, which provides information to the BS resource manager for determining the level of load in the queues of packets distributed among the MSs. In addition, it allows the BS resource manager to make reasonable decisions on purpose for competing MSs. Thus, the BS resource manager distributes resources among competing MSs, including the operation of a closed speed control loop during soft handoff.

Various aspects of the present invention will become more apparent when referring to the various steps depicted in FIG. 4. In FIG. 4 shows a message flow 400 and processing steps in a BS and an MS in a communication system 100. The receiver and transmitter systems 200 and 300 shown in FIG. 2 and 3, can work when performing various steps, if they are part of the corresponding base station or mobile station in the communication system 100. At step 401, the mobile station determines data packets for transmission for several communication services. At steps 402 and 403, respectively, the mobile station determines a transmission deadline for each data packet and places the data packets in a queue for transmission according to a specific transmission deadline. At steps 405, 406 and 407, respectively, the mobile station determines the data rate for transmitting data packets based on the placement of data packets in the queue, providing the opportunity to meet the transmission deadlines for each data packet, determines the duration of a certain data rate for transmitting data packets based on the placement of data packets in the specified queue, and transmits the value of the data rate and duration from the mobile station to the base station. At step 408, the base station determines whether available resources allow the base station to perform an assignment for transmission from a mobile station with a specific data rate and duration. At 409, the base station announces the approval of a specific data rate for transmitting data packets from the mobile station. At step 410, the mobile station transmits at an approved data rate. At step 411, the base station can send a notification of the change in the load level to the mobile station, which indicates that previously available resources cannot be assigned by the base station for transmission from the mobile station at a certain data rate. In steps 412, 413 and 414, the mobile station passes at least one data packet from the data packets in the queue to determine a new queue of data packets, the new data rate being lower than the previously determined data rate, and determining a new duration for use a certain new data rate for transmitting data packets when placing data packets in a new queue. Stream 400 proceeds to step 408 to repeat the determination of granting access or denial.

Those skilled in the art will recognize that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the indicated interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether this functionality will be implemented using hardware or software depends on the particular application and design constraints imposed on the entire system. Specialists in the art can implement this functionality in various ways for each specific application, but such an implementation should not be interpreted as going beyond the scope of the present invention.

The various illustrative logical blocks, modules, circuits described in connection with the embodiments disclosed herein may be implemented or executed using a general purpose processor, digital signal processor (DSP), custom integrated circuit (ASIC), programmable gate array (FPGA) or other programmable logic device, discrete gates or transistor logic, discrete hardware components, or any combination thereof designed to perform functions, and Proposition herein. A general purpose processor may be a microprocessor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of processors, one or more microprocessors in combination with a DSP core, or any other similar configuration.

The steps of a method or algorithm set forth in connection with the embodiments disclosed herein may be implemented directly in hardware, in the form of software modules executed by a processor, or a combination thereof. The software modules may be located in RAM, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other type of storage medium known in the art. An exemplary storage medium is coupled to the processor in such a way that said processor can read information and write information to the storage medium. Alternatively, the storage medium may be integrated into the processor. The processor and the storage medium may be part of the ASIC. ASIC may be part of a user terminal. Alternatively, the processor and the storage medium may form part of the user terminal as discrete components.

The previous description of the disclosed embodiments of the present invention is presented to enable any person skilled in the art to use the present invention. Various modifications to these embodiments of the present invention will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit and scope of the present invention. Thus, the present invention is not limited to the embodiments described herein, but should correspond to the broadest scope consistent with the principles and new features disclosed in the present description.

Claims (30)

1. In a communication system, a method for determining a data rate of a reverse link from a mobile station to a base station, comprising
determining data packets for transmission from the mobile station for several communication services;
determination of the expiration date of each of these data packets;
placing data packets in a queue for transmission according to the specified defined transmission deadlines;
determining the data transfer rate for transmitting data packets based on the placement of these data packets in the specified queue, providing the opportunity to meet the transmission deadlines for each specified data packet. 2. The method according to claim 1, further comprising transmitting said data rate from said mobile station to said base station. 3. The method according to claim 1, further comprising determining a time interval for using said specific data rate for transmitting data packets based on placing said data packets in said queue. 4. The method according to claim 3, further comprising transmitting said specified time interval from said mobile station to said base station. 5. The method according to claim 1, further comprising determining whether available resources allow an assignment to be made at a specified base station for transmission from a specified mobile station with a specified data rate. 6. The method according to claim 5, further containing an indication of a change in the load level of the indicated mobile station, if the specified definition of available resources does not allow the assignment at the indicated base station to be transmitted from the indicated mobile station with the specified transmission rate. 7. The method according to claim 6, further comprising skipping at least a data packet of said data packets in said queue to determine a new queue of data packets; determining a new data rate for transmitting said new data packet queue, said new data rate being lower than said data rate. 8. The method according to claim 7, further comprising determining a new time interval for using the specified specific new data rate for transmitting data packets based on the placement of said data packets in said new queue. 9. In a communication system, a method for determining a data rate of a reverse link from a mobile station to a base station, comprising
determining data packets for transmission from the mobile station for several communication services;
determination of the deadline for the transfer of each of these data packets;
placing data packets in several types of queue configurations for transmission according to the specified defined transmission deadlines;
determination of several data rates for the transmission of data packets based on several types of possible queue configurations. 10. The method according to claim 9, in which the specified number of determined data rates includes the requested data rate and at least one speed level of the data load. 11. The method according to claim 9, further comprising transmitting a specified number of data rates from said mobile station to said base station. 12. The method according to claim 9, further comprising determining a time interval for using each of a certain number of data rates for transmitting data packets based on the placement of said data packets in a specified queue. 13. The method according to item 12, further comprising transmitting the specified specific time interval from the specified mobile station to the specified base station. 14. The method according to claim 9, further comprising determining whether the available resources allow the assignment at the indicated base station to be transmitted from the indicated mobile station with at least one of the specified number of data rates. 15. The method according to 14, further containing an indication of the specified mobile station, if the specified definition of available resources allows you to assign in the specified base station for transmission from the specified mobile station, at least one of the specified data rates. 16. In a communication system, a device for determining a data rate of a reverse link from a mobile station to a base station, comprising
means for determining data packets for transmission from a mobile station for multiple communication services;
means for determining a transmission deadline for each of said data packets;
means for placing data packets in a queue for transmission according to the specified specific transmission deadlines;
means for determining a data rate for transmitting data packets based on the placement of said data packets in a specified queue, providing the ability to meet transmission deadlines for each specified data packet. 17. The device according to clause 16, further comprising means for transmitting said data rate from said mobile station to said base station. 18. The device according to clause 16, further comprising means for determining a time interval for using said specific data rate for transmitting data packets based on placing said data packets in said queue. 19. The device according to p. 18, additionally containing means for transmitting the specified specific time interval from the specified mobile station to the specified base station. 20. The device according to clause 16, additionally containing means for determining whether available resources allow you to assign in the specified base station for transmission from the specified mobile station with a specified data rate. 21. The device according to claim 20, further comprising means for indicating a change in the load level in the indicated mobile station, if the indicated determination of available resources does not allow the assignment in the indicated base station to be transmitted from the indicated mobile station with the specified transmission rate. 22. The device according to item 21, further containing
means for passing at least a data packet from said data packets in said queue to determine a new queue of data packets;
means for determining a new data rate for transmitting said new data packet queue, said new data rate being lower than said data rate. 23. The device according to item 22, further comprising means for determining a new time interval for using said specific new data rate for transmitting data packets based on placing said data packets in said new queue. 24. In a communication system, a device for determining a data rate of a reverse link from a mobile station to a base station, comprising
means for determining data packets for transmission from a mobile station for multiple communication services;
means for determining a transmission deadline for each of said data packets;
means for placing data packets in several types of queue configurations for transmission according to the specified specific transmission deadlines;
means for determining multiple data rates for transmitting data packets based on several types of possible queue configurations. 25. The device according to paragraph 24, in which the specified number of certain data rates includes the requested data rate and at least one speed level of the data load. 26. The device according to paragraph 24, further comprising means for transmitting a specified number of data rates from said mobile station to said base station. 27. The device according to paragraph 24, further comprising means for determining a time interval for using each of a certain number of data rates for transmitting data packets based on the placement of said data packets in a specified queue. 28. The device according to item 27, further comprising means for transmitting the specified specific time interval from the specified mobile station to the specified base station. 29. The device according to paragraph 24, further containing a means for determining whether available resources allow you to assign in the specified base station for transmission from the specified mobile station with at least one of the specified number of data rates. 30. The device according to clause 29, further containing a means for indicating the specified mobile station, if the specified definition of available resources allows you to assign in the specified base station for transmission from the specified mobile station, at least one of the specified data rates.

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