WO2010075706A1

WO2010075706A1 - Method and device for implementing hybrid automatic retransmission request (harq) based on time division duplex (tdd) system

Info

Publication number: WO2010075706A1
Application number: PCT/CN2009/074109
Authority: WO
Inventors: 王军虎; 王文焕; 孙波
Original assignee: 中兴通讯股份有限公司
Priority date: 2009-01-05
Filing date: 2009-09-22
Publication date: 2010-07-08
Also published as: CN101772073A

Abstract

The present invention discloses a method and device for implementing Hybrid Automatic Retransmission Request (HARQ) based on Time Division Duplex (TDD) system, wherein the method includes: the base station determines the retransmission interval of HARQ process based on the predetermined information and service requirement, wherein the retransmission interval is integral multiple of a wireless frame's time length, and the predetermined information includes the ratio of upstream subframe number to downstream subframe in a wireless frame, the distribution of the control channels, and the processing delay of upstream/downstream. By virtue of the technical solution of the present invention, according to different HARQ processes, the retransmission interval of HARQ process is set to be integral multiple of a wireless frame's time length, and the retransmission interval is updated based on the resource configuration, the retransmission delay is processed flexibly, so the flexibility of HARQ process is increased.

Description

TECHNICAL FIELD The present invention relates to the field of communications, and in particular, to a method and an apparatus for implementing a hybrid automatic repeat request based on a time division duplex system. BACKGROUND OF THE INVENTION Hybrid Automatic Retransmission Request (HARQ) is a technology proposed to overcome the influence of wireless mobile channel time-varying and multipath fading on signal transmission by automatically retransmitting a request. (Automatic Retransmission Request, called ARQ) and Forward Error Correction (FEC) are used in combination. Moreover, HARQ technology is one of the key technologies of the Long Term Evolution (LTE) system of the 3rd Generation Partnership Project (3GPP), which enables wireless mobile communication systems. Get higher system throughput and higher system stability and stability.

The HARQ technology combines ARQ and FEC. When the sender sends a data packet, it carries the error correction and error detection bits in each data packet. The receiver receives and parses the data packet from the sender, if the data is received. If the number of error bits of the packet is within the error correction capability of the FEC, the error can be corrected by the FEC itself, and the HARQ technique is not needed. If the error is serious, that is, the error bit data of the received packet has exceeded the FEC correction. If the error is faulty, the Negative Acknowledgement (NACK) response feedback is sent to notify the sender to resend the error packet. In this way, the receiver can obtain additional signal-to-noise ratio gain by combining multiple samples received, and obtain time diversity effect, thereby improving system throughput and performance. In the Time Division Duplex-Orthogonal Frequency Division Multiplexing (TDD-OFDM) system, the uplink and downlink are time-divisionally transmitted, and the base station and the terminal need certain processing for receiving data. Time, this will increase the processing delay of the data. In addition, frame alignment and propagation will also cause a certain delay. In order to reduce the time delay inherent in the Time Division Duple (TDD) system, the TDD system usually divides the Radio Frame into several smaller sub-frames (Sub-Frame). The data ratio of the frame and the uplink subframe may be determined according to a specific implementation, where the duration of one subframe is referred to as one transmission time interval (Transmit Time lnterval, the cylinder is called TTI). For example, Figure 1 is based on A schematic diagram of a structure of a radio frame of a related art TDD-OFDMA system. In the radio frame structure shown in FIG. 1, a radio frame is divided into 8 subframes: SF0, SF1, SF2, SF3, SF4, SF5, SF6, SF7, where SF0, SF1, SF2, SF3, and SF4 are downlink (downlink, DL) subframes, and SF5, SF6, and SF7 are uplink (uplink, UL) sub-frames, that is, DL/UL The ratio of the number is 5:3. Moreover, there are two uplink and downlink switching points in one radio frame. In the radio frame shown in FIG. 1, there is a lower uplink switching point between SF4 and SF5, and between SF7 and the first subframe of the next radio frame. There is an upstream and downstream switching point. Due to the processing delay of the TDD system, after receiving the data, the base station needs to process the delay to feed back ACK (positive acknowledgement/correct answer) or NACK (negative acknowledgement/error response) information; meanwhile, the terminal receives the base station After the feedback information, it is also subject to a certain processing delay, and then transmitted or retransmitted when the transmission condition is met. Currently, in the synchronous HARQ technology, the time of retransmission is fixed for each HARQ process, but the method of fixing the retransmission time has the following disadvantages:

1) There is a fixed requirement for the processing capability of the device, and it is not possible to support terminals with different processing capabilities at the same time. For example, after the system is upgraded, there is a new requirement for the processing speed of the terminal, which limits the access of the terminal with a large processing delay due to the low processing speed.

2) The support capability that does not adapt to the characteristics of multiple services. For example, the real-time service and the non-real-time service require different retransmission delays, and the system does not allow different services to have different retransmission delays according to the characteristics of the service. 3) The conflicts that occur during data transmission cannot be handled flexibly. For example, when the system is compatible with other systems, if the uplink resources of the system are occupied by other systems, the initial data or the retransmitted data cannot be in the predetermined uplink resources. Send on. At present, an effective solution has not been proposed for the problem of limiting terminal access, inability to adapt to multi-service features, and the inability to handle transmission resource conflicts caused by fixed retransmission times in related technologies. SUMMARY OF THE INVENTION The present invention has been made in view of the problem of restricting terminal access, support capability that does not adapt to multi-service characteristics, and the inability to handle transmission resource conflicts caused by the retransmission time existing in the related art, and the main purpose of the present invention is It is to provide an implementation scheme of a hybrid automatic repeat request based on a time division duplex system to solve the above problem. According to an aspect of the present invention, a method for implementing a hybrid automatic repeat request based on a time division duplex system is provided. The method for implementing the hybrid automatic repeat request based on the time division duplex system according to the present invention includes: the base station determines the retransmission interval of the HARQ process according to the predetermined information and the service requirement, where the retransmission interval is a radio frame duration Integer multiple, the predetermined information includes: the ratio of the number of uplink subframes and downlink subframes in the radio frame, the distribution of the control channel, and the processing delay of the uplink/downlink. The predetermined information may further include: a delay of processing the data by the terminal, where the determining, by the terminal, the retransmission interval of the HARQ process of the terminal includes: setting a correspondence between a delay of processing data by the terminal and a terminal level, where each terminal The levels respectively correspond to the corresponding predetermined delay ranges; the correspondence between the terminal level and the retransmission interval is set; and the retransmission interval of the HARQ process of the terminal is determined according to the delay of processing the data by the terminal. The service requirement is the real-time requirement of the service for the retransmission interval. Further, the foregoing method further includes: in the HARQ process, the base station updates the retransmission interval. Preferably, after the base station updates the retransmission interval, the method further includes: the base station sending the updated retransmission interval to the terminal in the control channel by using one of the following modes: a broadcast mode, a multicast mode, and a unicast mode. The retransmission interval includes one of the following: a time interval between the initial transmission of the data packet by the terminal and the first retransmission of the data packet, the nth retransmission of the data packet by the terminal, and the data packet ( n+1) The time interval between retransmissions, where n is a natural number greater than or equal to 1. The one HARQ process includes: the initial transmission of the data packet by the terminal, the feedback of the data packet received by the base station, and/or the retransmission of the data packet by the terminal, and each HARQ process occupies one or more uplinks in the radio frame. Subframe. According to another aspect of the present invention, an apparatus for implementing a hybrid automatic repeat request based on a time division duplex system is provided, and the apparatus may be located at a base station side. The device for implementing the hybrid automatic repeat request based on the time division duplex system according to the embodiment of the present invention includes: a determining module, configured to determine a retransmission interval of the HARQ process according to the predetermined information, where the retransmission interval is an integer of a radio frame duration The predetermined information includes: a ratio of the number of uplink subframes to downlink subframes in the radio frame, a distribution of control channels, and an uplink/downlink processing delay; and an update module, configured to update the retransmission interval in the HARQ process. According to the above at least one technical solution of the present invention, the retransmission interval is updated by setting the retransmission interval of the HARQ process to an integer multiple of the duration of the radio frame for different HARQ processes, and comparing the resource allocation situation. In the prior art, the retransmission delay can be flexibly processed, thereby improving the flexibility of the HARQ process. The drawings are intended to provide a further understanding of the invention, and are intended to be a part of the description of the invention. In the drawings: FIG. 1 is a schematic structural diagram of a radio frame of a TDD-OFDMA system according to the related art; FIG. 2 is a schematic diagram of a method for implementing a hybrid automatic retransmission request based on a time division duplex system according to the related art. FIG. 3 is a 3D diagram of a method for implementing a hybrid automatic repeat request based on a time division duplex system according to an embodiment of the present invention; FIG. 4 is a flowchart of a process for performing capability negotiation between a base station and a terminal according to an embodiment of the present invention. Figure 5 is a schematic view of Embodiment 1 of the method shown in Figure 3; Figure 6 is a schematic view of Embodiment 2 of the method shown in Figure 3; Figure 7 is a UL/DL according to an embodiment of the present invention. A schematic diagram of a 2:6 HARQ timing mechanism; FIG. 8 is a schematic diagram of a HARQ timing mechanism with a UL/DL of 3:5 according to an embodiment of the present invention; FIG. 9 is a UL/DL according to an embodiment of the present invention. Schematic diagram of a 4:4 HARQ timing mechanism; FIG. 10 is a schematic diagram of a HARQ timing mechanism with a UL/DL of 5:3 according to an embodiment of the present invention; FIG. 11 is a UL/DL according to an embodiment of the present invention. Schematic representation of the 6:2 HARQ timing mechanism FIG. 12 is a structural block diagram of an apparatus for implementing a hybrid automatic repeat request based on a time division duplex system according to an embodiment of the present invention. The embodiments of the present invention provide an improved synchronous retransmission mechanism. In the technical solution of the embodiment of the present invention, the base station can Determining the retransmission interval of the HARQ process of the terminal according to the configuration ratio of the uplink subframe and the downlink subframe in the radio frame, the distribution of the control channel, and the uplink and downlink processing delay, and the base station sets the retransmission interval to one radio. The integer multiple of the frame duration, the terminal performs data retransmission according to the retransmission interval. In the HARQ process, the base station may also update the retransmission interval according to the resource configuration of the radio frame. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict. The preferred embodiments of the present invention are described with reference to the accompanying drawings, and the preferred embodiments of the present invention are intended to illustrate and explain the invention. In the following embodiments, the steps illustrated in the flowchart of the drawings may be performed in a computer system such as a set of computer executable instructions, and although the logical order is illustrated in the flowchart, in some cases The steps shown or described may be performed in an order different from that herein. For ease of understanding, before the embodiment of the present invention is described, the implementation method of the uplink hybrid automatic repeat request in the related art is first described in conjunction with FIG. 2, and FIG. 2 is a hybrid based on the time division duplex system according to the related art. Flowchart of an implementation method of an automatic retransmission request. The synchronous HARQ means that the transmission (retransmission) of one HARQ process occurs at a fixed time. Since the receiving end knows the time of transmission in advance, no additional signaling overhead is required to indicate the time of retransmission. Step S201: The base station allocates, by using the control signaling on the downlink control channel, the uplink resource that sends the data to the terminal, and the terminal sends the initial data or the retransmitted data to the base station on the allocated uplink subframe resource, and starts the HARQ process. Step S202 The base station receives the initial transmission data or the retransmission data from the terminal, and sends the feedback information to the terminal in the corresponding downlink control channel. If the feedback information is a negative information (NACK), the process proceeds to step S203; if the feedback information is the confirmation information (ACK), proceeding to step S204; Step S203: The terminal receives the NACK information, and determines whether the retransmission of the data reaches the maximum number of retransmissions. If the number of retransmissions is reached, the process proceeds to step S204. Otherwise, the terminal requests the retransmission interval specified by the HARQ process to be in the corresponding uplink. The data is retransmitted on the subframe, and the process proceeds to step S201; in step S204, the terminal terminates the HARQ process. Method Embodiments According to an embodiment of the present invention, a method for implementing a hybrid automatic repeat request based on a time division duplex system is provided. 3 is a flowchart of a method for implementing a hybrid automatic repeat request based on a time division duplex system according to an embodiment of the present invention. As shown in FIG. 3, the method includes the following steps (step S302 to step S304). Step S302, the base station determines the retransmission interval of the HARQ process according to the predetermined information and the service requirement, where the retransmission interval is an integer multiple of the duration of one radio frame, and the predetermined information includes: the number of uplink subframes and downlink subframes in the radio frame Ratio, control channel distribution, uplink/downlink processing delay; wherein each HARQ process occupies one or more uplink subframes in the radio frame, and each

The HARQ process includes: the initial transmission of the data packet by the terminal, the feedback of the data packet received by the base station, and/or the retransmission of the data packet by the terminal, the feedback of the correct response feedback or the error response feedback, and if the feedback is the correct response feedback, the HARQ The process performs the initial transmission of the data packet by the terminal and the feedback of the data packet received by the base station. If the feedback is correct response feedback, the terminal performs initial transmission of the data packet, feedback of the base station to the received data packet, and weight of the terminal to the data packet. The retransmission interval includes one of the following: a time interval between the initial transmission of the data packet by the terminal and the first retransmission of the data packet, the nth retransmission of the data packet by the terminal, and the data packet. (n+1) The time interval between retransmissions, where n is a natural number greater than or equal to 1. It should be noted that the duration of the radio frames may be different in different communication systems. For example, in an LTE system, the duration of one radio frame is 10 ms, but the global interoperability for Microwave Access is available. In the system called the Wimax system, the duration of one radio frame is 5 ms. For different systems, the HARQ process can have different retransmission intervals. Step S304, in the HARQ process, the base station can report the configuration of the resources in the radio frame. After the retransmission interval is updated, the base station sends an updated retransmission interval to the terminal in one of the following manners in the control channel: broadcast mode, multicast mode, and unicast mode. According to the technical solution provided by the embodiment of the present invention, the retransmission interval of the HARQ process is set to an integer multiple of the duration of the radio frame for different HARQ processes, and the retransmission interval is updated according to the resource configuration. In the prior art, the retransmission delay can be flexibly handled, thereby improving the flexibility of the HARQ process. In the specific processing, the foregoing predetermined information may further include a delay length of the data processed by the terminal, and the base station determines the retransmission interval of the HARQ process of the terminal according to the delay of the data processed by the terminal, and the specific operation is: setting the terminal to process the data. Corresponding relationship between the delay and the terminal level, so that each terminal level corresponds to a corresponding predetermined delay range; setting a correspondence between the terminal level and the retransmission interval; the processing principle may be: the delay of processing data by the terminal is larger, The higher the retransmission interval of the terminal is, the smaller the delay of processing data by the terminal is. The higher the level of the terminal is, the smaller the retransmission interval corresponding to the terminal is. In this way, the base station can support users with different processing speed capabilities according to the speed or capability of the terminal to process data, and set different retransmission intervals for different terminals, thereby improving the flexibility of the HARQ process. In addition, the foregoing service requirements are mainly real-time requirements for the retransmission interval of the service, and the base station determines the retransmission interval of the HARQ process of the service according to the real-time nature of the service. For example, for a service with high real-time requirements, the base station can schedule the retransmission. For the non-real-time service, the non-real-time service is scheduled to be transmitted on the HARQ process with a long retransmission interval, that is, the higher the real-time performance of the service, the smaller the retransmission interval corresponding to the service, and conversely, the service The lower the real-time performance, the larger the retransmission interval corresponding to the service. In this way, the base station sets different retransmission intervals for different services according to the real-time nature of the service, thereby improving the flexibility of the HARQ process. FIG. 4 is a flowchart of a process for performing capability negotiation between a base station and a terminal according to an embodiment of the present invention. As shown in FIG. 4, the following processing is included (step S401 to step S404). Step S401: The base station and the terminal perform basic capability negotiation, learn the processing delay level of the terminal, and determine the HARQ process retransmission interval of the terminal according to the processing delay level of the terminal. Step S402: The base station determines the terminal according to the level of the terminal. Whether the retransmission interval of 5ms is supported, if the determination result is yes, go to step S404, otherwise, go to step S403; in step S403, the base station determines the retransmission interval of the terminal as 10ms, and the process ends; Step S404, the base station determines the retransmission interval of the terminal as 5 ms and/or 10 ms, and the process ends. A method for implementing a hybrid automatic repeat request based on a time division duplex system according to an embodiment of the present invention will be described in detail below with reference to FIG. 5 and FIG. When the terminal accesses the network, the base station processes the HARQ retransmission interval. When the terminal accesses the network, the base station performs the basic capability negotiation with the terminal to learn the processing delay level of the terminal, and determines the HARQ process of the terminal according to the processing delay level of the terminal. Retransmission interval. For example, in the frame structure shown in FIG. 1, the retransmission interval may include 5ms, 10ms, and the like. The specific processing procedure for the capability negotiation between the base station and the terminal is shown in FIG. 4, and details are not described herein again. For a terminal that supports a 5 ms retransmission delay, the base station schedules the uplink transmission data of the terminal, and the terminal transmits the initial transmission data or retransmits the data on the HARQ process with the retransmission interval of 5 ms. For the terminal supporting the 10 ms retransmission delay, The base station schedules the uplink transmission data of the terminal, and the terminal transmits the initial transmission data or retransmits the data on the HARQ process with the retransmission interval of 10 ms. In addition, for a terminal that supports a 5 ms retransmission delay, the base station may also schedule uplink transmission data of the terminal, and the terminal transmits the initial transmission data or retransmits the data on the HARQ process with the retransmission delay of 5 ms. FIG. 5 is a schematic diagram of Embodiment 1 according to the method shown in FIG. 3. As shown in FIG. 5, one superframe is composed of four 5 ms radio frames, and each radio frame includes three uplink subframes and five downlinks. The subframes, SF0, SF1, and SF2 are uplink subframes, and SF3, SF4, SF5, SF6, and SF7 are downlink subframes. The one or more uplink subframes may constitute an uplink HARQ process, for example, the HARQ processes 1, 2, 3, and 4. 1 It is assumed that the terminal 1 supports a retransmission interval of 5 ms, and the terminal 2 only supports a retransmission interval of 10 ms. As shown in FIG. 5, the base station scheduling terminal 1 performs initial transmission and retransmission of data on the HARQ process 1 and the HARQ process 2, and performs ACK/NACK feedback on the downlink control channels 2, 5, 8, and 11, and the HARQ process The retransmission interval is the length of time of one radio frame, that is, 5 ms; the base station scheduling terminal 2 performs initial transmission and retransmission of data on the HARQ process 3 or the HARQ process 4, and performs ACK on the downlink control channels 3, 6, 9, and 12. /NACK feedback, the retransmission interval of the J HARQ process is the length of time of two radio frames, that is, 10 ms. Method for updating the retransmission interval by the base station FIG. 6 is a schematic diagram of Embodiment 2 of the method according to FIG. As shown in FIG. 6, the base station schedules the terminal 1 in HARQ process 1 and HARQ according to the configuration and transmission of resources in the radio frame. The initial transmission and retransmission of the data are performed on the process 2, the interval of the first retransmission is 5 ms, and the interval of the second retransmission is 10 ms, wherein the base station notifies the terminal 1 of the change of the retransmission interval in the control channel 5. And, in the control channel 5, the base station may send the updated retransmission interval to the terminal in one of the following manners: a broadcast mode, a multicast mode, and a unicast mode, where the base station notifies the terminal that the retransmission interval changes. The message format, in this way, the base station can handle the resource conflict problem in the uplink burst service by updating the retransmission interval. Table 1

The method for determining, by the base station, the retransmission interval of the HARQ process according to the configuration of the uplink/downlink subframe and the control channel, includes 32 subframes, SF0 to SF31, in a superframe, and sequentially labels each uplink HARQ process, and each The downlink control channels are labeled; the correspondence between the uplink HARQ process, the control channel for transmitting feedback information, and the retransmission interval is established. The HARQ process represents the label of the uplink HARQ process, and one uplink HARQ process may include one subframe or multiple consecutive subframes; the control channel refers to the control channel of the ACK/NACK fed back by the base station, the label of the HARQ process, and the control channel. The labels are sequentially numbered within the superframe range. 7 to FIG. 11 describe the HARQ timing mechanism in the case of different uplink-downlink ratios, and different correspondences are established for different HARQ timing mechanisms, which will be specifically described below. FIG. 7 is a schematic diagram of a HARQ timing mechanism with a UL/DL of 2:6 according to an embodiment of the present invention. As shown in FIG. 7, a radio frame is divided into 8 subframes: SF0, SF1, SF2, SF3, SF4. SF5, SF6, and SF7, where SF0 and SF1 are uplink subframes (UL), and SF2, SF3, SF4, SF5, SF6, and SF7 are downlink subframes (DL), that is, the ratio of the number of UL/DLs is 2: 6. In addition, there is an uplink and downlink switching point between SF1 and SF2, and an uplink and downlink switching point exists between SF7 and the first subframe of the next radio frame, and the uplink and downlink processing delays are assumed to be two subframes. length. According to the schematic diagram of the HARQ timing mechanism shown in FIG. 7, Table 2 is based on ΗΑΤί Γ» shown in FIG. The corresponding relationship between the timing mechanisms is as shown in the following Table 2. The HARQ process with the HARQ process number 1 corresponds to the control channel number of 2, the retransmission interval is 5 ms, and the HARQ process number 2 HARQ process retransmission interval is 5 ms. The feedback information of the HARQ process is transmitted on the control channel with the control channel number 2, that is, different HARQ processes correspond to the same retransmission interval, and the feedback information is transmitted on the same control channel. Table 2

8 is a schematic diagram of a HARQ timing mechanism with a UL/DL of 3:5 according to an embodiment of the present invention. As shown in FIG. 8, ^) a radio frame is divided into 8 subframes: SF0, SF1, SF2, SF3 SF4, SF5, SF6, SF7, where SF0, SF1, SF2, SF3, and SF4 are uplink (UL) subframes, and SF5, SF6, and SF7 are downlink (DL) subframes, that is, the ratio of the number of UL/DLs is 3: 5. Moreover, there is an uplink and downlink switching point between SF2 and SF3, and there is a lower uplink switching point between the SF7 and the first subframe of the next radio frame. According to the schematic diagram of the HARQ timing mechanism shown in FIG. 8, Table 3 is based on the correspondence relationship of the HARQ timing mechanism shown in FIG. 8. As shown in Table 3 below, the retransmission interval corresponding to the HARQ process with the HARQ process number 1 is 5 ms, and The feedback information of the HARQ process is transmitted on the control channel whose control channel numbers are 2, 5, 8, and 11 respectively; the retransmission interval of the HARQ process with the HARQ process number 2 is 5 ms, and the feedback information of the HARQ process is under control. The channel numbers are respectively transmitted on the control channels of 2, 5, 8, and 11, that is, different HARQ processes correspond to the same retransmission interval, and the feedback information is transmitted on the same control channel. The retransmission interval corresponding to the HARQ process with the HARQ process number 3 is 10 ms, and the feedback information of the HARQ process is transmitted on the control channel with the control channel numbers 3 and 9, respectively; the HARQ process with the HARQ process number 4 is retransmitted. The interval is 10 ms, and the feedback information of the HARQ process is transmitted on the control channel whose control channel numbers are 6, 12 respectively, that is, different HARQ processes correspond to the same retransmission interval, but the feedback information is transmitted on different control channels. table 3

3 3 , 9 10ms

4, 12 10ms FIG. 9 is a schematic diagram of a HARQ timing mechanism with a UL/DL of 4:4 according to an embodiment of the present invention. As shown in FIG. 9, a radio frame is divided into 8 subframes: SF0, SF1. SF2, SF3, SF4, SF5, SF6, SF7, where SF0, SF1, SF2, and SF3 are uplink subframes (UL), and SF4, SF5, SF6, and SF7 are downlink subframes (DL), that is, the number of UL/DLs The ratio is 4: 4. Moreover, there is an uplink and downlink switching point between SF3 and SF4, and there is a lower uplink switching point between SF7 and the first subframe of the next radio frame. According to the schematic diagram of the HARQ timing mechanism shown in FIG. 9, Table 4 is based on the corresponding relationship of the HARQ timing mechanism shown in FIG. 9. As shown in Table 4 below, the retransmission interval corresponding to the HARQ process with HARQ process numbers 1 and 2 is 10 ms, and the feedback information of the two processes is transmitted on the control channel whose control channel numbers are 2 and 6 respectively; the retransmission interval corresponding to the HARQ process with the HARQ process numbers 3 and 4 is 10 ms, and the two processes are The feedback information is transmitted on the control channel with the control channel numbers 3 and 7, respectively; the retransmission interval corresponding to the HARQ process with the HARQ process numbers 5 and 6 is 10 ms, and the feedback information of the two processes is in the control channel sequence number. The transmission channels are respectively transmitted on the control channels of 4 and 8. The retransmission interval corresponding to the HARQ processes with HARQ process numbers 7 and 8 is 10 ms, and the feedback information of the two processes is 5, (1) Transmission on the control channel. Wherein, (1) represents the first control channel of the next radio frame adjacent to the radio frame, and USCCH in Table 4 refers to a Unicast Service Control Channel. Table 4

10 is a schematic diagram of a HARQ timing mechanism with a UL/DL of 5:3 according to an embodiment of the present invention, As shown in FIG. 10, a radio frame is divided into 8 subframes: SF0, SF1, SF2, SF3, SF4, SF5, SF6, SF7, where SF0, SF1, SF2, SF3, and SF4 are uplink subframes (UL ), SF5, SF6, and SF7 are downlink subframes (DL), that is, the ratio of the number of UL/DLs is 5:3. Moreover, there are two uplink and downlink switching points in one radio frame, one uplink and downlink switching point exists between SF4 and SF5, and one lower uplink switching point exists between SF7 and the first subframe of the next radio frame. According to the schematic diagram of the HARQ timing mechanism shown in FIG. 10, Table 5 is based on the correspondence relationship of the HARQ timing mechanism shown in FIG. 10, as shown in Table 5 below, the retransmission interval corresponding to the HARQ process with HARQ process numbers 1, 2, and 3. 5 ms, and the feedback information of the three processes is transmitted on the control channel whose control channel numbers are 1, 3, 5, and 7, respectively; the retransmission interval corresponding to the HARQ process with the HARQ process numbers 4 and 5 is 5 ms. And the feedback information of the two processes is transmitted on the control channel whose control channel numbers are 2, 4, 6, and 8, respectively. table 5

11 is a schematic diagram of a HARQ mechanism with a UL/DL of 6:2 according to an embodiment of the present invention. As shown in FIG. 11, a radio frame is divided into 8 subframes: SF0, SF1, SF2, SF3, SF4, SF5, SF6, SF7, where SF0, SF1, SF2, SF3, SF4, and SF5 are uplink subframes ( UL), SF6, SF7 are downlink subframes (DL), that is, the ratio of the number of UL/DL is 6:2. Moreover, there is an uplink and downlink switching point between SF5 and SF6, and there is a lower uplink switching point between the SF7 and the first subframe of the next radio frame. According to the schematic diagram of the HARQ timing mechanism shown in FIG. 11, Table 6 is based on the correspondence between the HARQ timing mechanisms shown in FIG. 11, and the retransmission interval corresponding to the HARQ process with HARQ process numbers 1 and 2 is the same as shown in the following Table 6. 10 ms, and the feedback information of the two processes is transmitted on the control channel whose control channel numbers are 1, 5 respectively; the retransmission interval of the HARQ process with the HARQ process number 3 is 5 ms, and the feedback information of the HARQ process is under control. Controls with channel numbers 1 and 5 respectively The transmission is performed on the channel; the retransmission interval corresponding to the HARQ process with the HARQ process numbers 4 and 5 is 5 ms, and the feedback information of the two processes is on the control channel with the control channel numbers 2, 4, 6, and 8, respectively. The retransmission interval corresponding to the HARQ process with the HARQ process numbers of 6, 7, and 8 is 10 ms, and the feedback information of the three processes is transmitted on the control channel whose control channel numbers are 3 and 7, respectively; The retransmission interval of the HARQ process of number 9 is 10 ms, and the feedback information of the HARQ process is transmitted on the control channel whose control channel numbers are respectively 5, (1), where (1) indicates that the radio frame is adjacent to the radio frame. The first control channel of the next radio frame. Table 6

Apparatus Embodiment According to an embodiment of the present invention, an apparatus for implementing a hybrid automatic repeat request based on a time division duplex system is provided. FIG. 12 is a structural block diagram of an apparatus for implementing a hybrid automatic repeat request based on a time division duplex system according to an embodiment of the present invention. The apparatus may be located at a base station side, as shown in FIG. 12, and includes a determining module 10 and an updating module 20. The determining module 10 is configured to determine, according to the predetermined information, a retransmission interval of the HARQ process, where the retransmission interval is an integer multiple of a radio frame duration, and the predetermined information includes: a ratio of an uplink subframe to a downlink subframe in the radio frame, Control channel distribution, uplink/downlink processing delay; update module 20, used to update the retransmission interval in the HARQ process. The HARQ process includes: the initial transmission of the data packet by the terminal, the feedback of the data packet received by the base station, and/or the retransmission of the data packet by the terminal, and the feedback of the correct response feedback or the error response feedback, such as If the feedback is the correct response feedback, the HARQ process performs the initial transmission of the data packet by the terminal and the feedback of the data packet received by the base station. If the feedback is the correct response feedback, the terminal performs the initial transmission of the data packet, and the base station receives the data packet. The feedback and the retransmission of the data packet by the terminal; the retransmission interval includes one of the following: a time interval between the initial transmission of the data packet by the terminal and the first retransmission of the data packet, and the terminal performing the nth data packet The time interval between the second retransmission and the (n+1)th retransmission of the data packet, where n is a natural number greater than or equal to 1. According to the foregoing apparatus of the embodiment of the present invention, the retransmission interval of the HARQ process is set to an integer multiple of the duration of a radio frame for different HARQ processes, and the retransmission interval is updated according to the resource configuration. There is a technology that can flexibly handle retransmission delays, thereby increasing the flexibility of the HARQ process. In summary, the implementation of the hybrid automatic repeat request based on the time division duplex system provided by the embodiment of the present invention sets the retransmission interval of the HARQ process to an integer of a radio frame duration for different HARQ processes. In addition, according to the resource configuration, the retransmission interval is updated. Compared with the prior art, the retransmission delay can be flexibly processed, thereby improving the flexibility of the HARQ process. In addition, the system supports users with different processing speed capabilities, and sets different feedback delays for their processing speed capabilities. Different service characteristics can be used to implement different services with different retransmission delays; Problem; Support for multiple TTI scheduling. This scheme can be applied to time division duplex systems, for example, TDD-OFDM systems. Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general-purpose computing device, which can be concentrated on a single computing device or distributed over a network composed of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device, such that they may be stored in the storage device by the computing device, or they may be separately fabricated into individual integrated circuit modules, or they may be Multiple modules or steps are made into a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A method for implementing a hybrid automatic repeat request based on a time division duplex system, comprising:

The base station determines the retransmission interval of the HARQ process according to the predetermined information and the service requirement, where the retransmission interval is an integer multiple of a radio frame duration, and the predetermined information includes: an uplink subframe and a downlink subframe in the radio frame. The ratio of the number, the distribution of the control channel, and the processing delay of the uplink/downlink.

The method according to claim 1, wherein the predetermined information further comprises: a delay of processing data by the terminal.

The method according to claim 1, wherein the service requirement is a real-time requirement of the service for the retransmission interval.

The method according to claim 2, wherein the determining a retransmission interval of the HARQ process of the terminal comprises:

Setting a correspondence between a delay of processing data by the terminal and a terminal level, where each terminal level respectively corresponds to a corresponding predetermined delay range;

Set the correspondence between the terminal level and the retransmission interval;

The retransmission interval of the HARQ process of the terminal is determined according to the delay of processing data by the terminal.

The method according to any one of claims 1 to 4, further comprising:

In the HARQ process, the base station updates a retransmission interval.

The method according to claim 5, wherein, after the base station updates the retransmission interval, the method further includes:

The base station sends the updated retransmission interval to the terminal in the control channel by using one of the following modes: a broadcast mode, a multicast mode, and a unicast mode.

The method according to any one of claims 1 to 4, wherein the retransmission interval comprises one of: a terminal performing initial transmission of a data packet and performing a first retransmission of the data packet The time interval between the time interval between the terminal retransmitting the data packet and the (n+1)th retransmission of the data packet, where n is a natural number greater than or equal to .

The method according to any one of claims 1 to 4, wherein the HARQ process comprises: a terminal performing initial transmission of a data packet, a base station receiving feedback on the received data packet, and/or a terminal Retransmission of the data packet.

The method according to any one of claims 1 to 4, wherein the HARQ process occupies one or more uplink subframes in the radio frame.

An apparatus for implementing a hybrid automatic repeat request based on a time division duplex system, located at a base station side, wherein the apparatus includes: a determining module, configured to determine a retransmission interval of a HARQ process according to predetermined information, where The retransmission interval is an integer multiple of a radio frame duration, and the predetermined information includes: a ratio of an uplink subframe to a downlink subframe in a radio frame, a distribution of a control channel, and an uplink/downlink processing delay;

And an update module, configured to update the retransmission interval in the HARQ process.