WO2011143895A1

WO2011143895A1 - Data retransmission method, base station, terminal, and wireless communication system

Info

Publication number: WO2011143895A1
Application number: PCT/CN2010/077847
Authority: WO
Inventors: 宁丁; 关艳峰; 鲁照华
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-05-17
Filing date: 2010-10-18
Publication date: 2011-11-24
Also published as: CN102255709B; CN102255709A

Abstract

A data retransmission method, base station, terminal, and wireless communication system are provided by the present invention. Said data retransmission method comprises: a base station sets Hybrid-Automatic-Repeat-Request (HARQ) Maximum-Retransmission-Interval based on a retransmission parameter (S302), wherein said retransmission parameter includes frame structure of the data frame and/or Maximum-Retransmission-Times; said base station determines a control channel signaling transmitted on the control channel based on said HARQ Maximum-Retransmission-Interval (S304), wherein said control channel signaling includes retransmission interval indication information; said base station transmits said retransmission parameter and said control channel signaling to a terminal (S306); said terminal determines said HARQ Maximum-Retransmission-Interval based on said retransmission parameter and said control channel signaling (S308); said terminal and said base station retransmit data packets based on said HARQ Maximum-Retransmission-Interval (S310). By use of the present invention, the base station and the terminal could know the HARQ Maximum-Retransmission-Interval merely by one signaling transmission while retransmitting data, so the signaling overhead can be effectively saved.

Description

The present invention relates to the field of communications, and in particular to a Hybrid Automatic Repeat Request (HARQ) data retransmission method, a base station, and a terminal. And wireless communication systems. A Hybrid Automatic Repeat Request (HQQ) technology is an improvement over the traditional automatic repeat request (ARQ) technology. HARQ technology combines ARQ technology and forward error correction (FEC) technology to reduce the impact of time-varying fading channels on the bit error rate of received data, enabling wireless communication systems to provide higher and more stable data throughput.

The working mechanism of HARQ is that the transmitting end sends a data packet A to the receiving end, and the receiving end decodes and feeds back ACK or NACK to the transmitting end, ACK indicates that the decoding is successful, and NACK indicates that the decoding fails. If the sender receives a NACK and retransmits a packet B, the packets A and B may be different, and then the receiving end receives the data packets A and B received twice. If the continuation is unsuccessful, the sender will always send the data packet until the decoding succeeds or the number of retransmissions reaches the maximum number of retransmissions N MAX ReTx. The maximum number of retransmissions N MAX ReTx includes the downlink maximum retransmission times DL N MAX ReTx and the uplink maximum retransmission times UL N MAX ReTx. In a Frequency Division Duplex (FDD) system, the uplink/downlink can simultaneously transmit data or signals. In order to reduce the system delay due to the system link structure and to flexibly allocate the data payload on the uplink/downlink, one radio frame is usually further divided into a plurality of subframes with smaller time granularity. The number of subframes (that is, the length of time) occupied by one data packet is TTI (Transmission Time Interval). In the radio frame structure shown in FIG. 1, a radio frame is divided into 8 sub-frames, and all radio frames are sequentially numbered according to the principle of sequential increment, which is referred to as a frame number, as shown in FIG. The frame is denoted as SF0-SF7, where the uplink and the downlink have the same frame structure. In a Time Division Duplex (TDD) system, for OFDM (Orthogonal Frequency Division Multiplexing) or In the wireless communication system of the OFDMA (Orthogonal Frequency Division Multiple Access), the radio resource mapping is mainly based on the frame structure and resource structure of the radio communication system, and the frame structure describes the control structure of the radio resources in the time domain. The resource structure describes the control structure of the radio resources in the frequency domain. The frame structure divides the radio resources into different levels of units in the time domain, such as a superframe, a frame, a subframe, and a symbol, by setting different control channels (for example, a broadcast channel). , unicast and multicast channels, etc.) Implement scheduling control. For example, as shown in FIG. 2, the radio resource is divided into super frames in the time domain, each super frame includes 4 frames, each frame includes 8 subframes, and the sub frame is composed of 6 basic OFDMA symbols, and the actual system is based on Factors such as the bandwidth to be supported and/or the cyclic prefix length of the OFDMA symbol determine how many OFDMA symbols are included in each level unit in the frame structure. Each of the frames may include thousands of downlink subframes and uplink subframes, and the data packets sent in the downlink subframe are sent by the base station to the terminal, and the terminal performs HARQ feedback through the uplink subframe. Similarly, the uplink subframe transmits the uplink subframe. The data packet is sent by the terminal to the base station, and the base station performs HARQ feedback through the downlink subframe. As frequency resources become increasingly scarce, base stations need to support multiple different bandwidths (for example, 5 MHz,

10MHz or 20MHz, sometimes system bandwidth is also called bandwidth) or multi-carrier operation to take advantage of different frequency resources and meet the needs of different operators. It should be noted that in some OFDM or OFDMA communication systems (for example, Worldwide Interoperability for Microwave Access (Wimax) 16m communication system), bandwidth and system Fast Fourier Transformation (Fast Fourier Transformation, Referred to as FFT) There is a corresponding relationship between the points, that is, as long as the bandwidth of the system is known, the number of FFT points of the system can be determined. In the downlink HARQ retransmission process, the base station sends a data packet to the terminal, and the terminal sends an ACK/NACK at a fixed time, and if the base station receives a NACK, the last transmission is not successful, if the number of retransmissions is not yet To reach the maximum number of retransmissions allowed by the system, the base station must send a retransmission packet of the data packet to the terminal. In some communication systems, such as the Wimax 16m communication system, the time for retransmitting the retransmission packet is not completely fixed, but the base station flexibly schedules according to its own situation, and notifies the terminal when retransmission, so two There is a time interval between transmissions. Due to the needs of the communication system and the HARQ mechanism, both the base station and the terminal must know the maximum value of the time interval, or the HARQ maximum retransmission interval MAX_Interval. The maximum value of this parameter can be notified in the broadcast channel (super frame header) and A-MAP (Advanced MAP, Service Control Channel), or in other control channel ports AAI-SCD (Advanced Air Interface System Configuration Descriptor). Sent in the system configuration description). The same reason, in some communication systems The retransmission time of the upstream HARQ is also not fixed. A parameter UL MAX Interval is also required, and both the base station and the terminal know the value of this parameter. In the related art, when the control channel is used to transmit the parameter MAX Interval, the signaling sent in the control channel is the number of binary bits, and the correspondence between the binary number and the specific time is uncertain, so additional use is needed. The signaling clearly informs the terminal of the exact value of the parameter. This causes a problem that the signaling overhead of the maximum retransmission time interval is notified when the HARQ is retransmitted. SUMMARY OF THE INVENTION A primary object of the present invention is to provide a data retransmission method, a base station, a terminal, and a wireless communication system to solve the problem of signaling a large retransmission time interval with a large signaling overhead when the HARQ retransmission is performed. According to an aspect of the present invention, a data retransmission method is provided, including: a base station retransmission parameter setting HARQ maximum retransmission interval, the retransmission parameter including a frame structure of a data frame and/or a maximum number of retransmissions The base station determines, according to the HARQ maximum retransmission interval, control channel signaling sent on the control channel, the control channel signaling includes retransmission interval indication information; the base station sends retransmission parameters and control channel signaling to the terminal; and the terminal according to the retransmission parameter And the control channel signaling determines the HARQ maximum retransmission interval; the terminal and the base station retransmit the data packet according to the HARQ maximum retransmission interval. Preferably, the step of determining, by the base station, the control channel signaling sent on the control channel according to the HARQ maximum retransmission interval comprises: the base station selecting a retransmission relationship table according to the retransmission parameter, where the retransmission relationship table includes a HARQ maximum retransmission interval and a weight Transmitting the correspondence between the indication information; the base station searches for the retransmission interval indication information corresponding to the HARQ maximum retransmission interval from the selected retransmission relationship table, and determines the control channel signaling. Preferably, the correspondence between the HARQ maximum retransmission interval and the retransmission interval indication information is determined by: the base station retransmission parameter sets a retransmission offset, and the retransmission offset is an integer greater than or equal to 0; The transmission interval indication information, the sum of the HARQ retransmission interval base value, and the retransmission offset are equal to the HARQ maximum retransmission interval. Preferably, the step of determining, by the terminal, the HARQ maximum retransmission interval according to the retransmission parameter and the control channel signaling comprises: the terminal selecting the retransmission relationship table stored by the terminal according to the retransmission parameter; the terminal determining and controlling the control channel from the selected retransmission relationship table. The retransmission interval of the signaling indicates the HARQ maximum retransmission interval corresponding to the information. Preferably, the frame structure comprises at least one of the following: system bandwidth, fast Fourier transform FFT points, number of downlink subframes per frame, number of uplink subframes per frame, total number of subframes per frame, number of symbols per frame, and cyclic prefix of symbols CP length. Preferably, the maximum number of retransmissions includes the maximum number of retransmissions in the downlink and/or the maximum number of retransmissions in the uplink. Preferably, the signaling of the control channel comprises at least one of: signaling of a broadcast control channel SFH, signaling of a service control channel A-MAP channel, and signaling of a system configuration description SCD channel. According to another aspect of the present invention, a data retransmission method is further provided, including: a base station setting a HARQ maximum retransmission interval according to a retransmission parameter, where the retransmission parameter includes a frame structure of a data frame and/or a maximum number of retransmissions The base station sends the retransmission parameter to the terminal; the terminal determines the HARQ maximum retransmission interval according to the retransmission parameter; the terminal and the base station retransmit the data packet according to the HARQ maximum retransmission interval. Preferably, the step of the base station setting the HARQ maximum retransmission interval according to the retransmission parameter comprises: the base station reading the retransmission relationship table according to the retransmission parameter, where the retransmission relationship table includes a correspondence between the retransmission parameter and the HARQ maximum retransmission interval; The HARQ maximum retransmission interval corresponding to the retransmission parameter is determined in the transmission relationship table. Preferably, the correspondence between the retransmission parameter and the HARQ maximum retransmission interval is determined by: the base station setting a retransmission offset according to the retransmission parameter; and the base station setting the retransmission offset to correspond to the sum of the base values of the HARQ retransmission interval The HARQ maximum retransmission interval for retransmitting parameters. Preferably, the step of determining, by the terminal, the HARQ maximum retransmission interval according to the retransmission parameter comprises: the terminal reading the retransmission relationship table stored by the terminal according to the retransmission parameter; and determining, by the terminal, the HARQ maximum corresponding to the retransmission parameter from the retransmission relationship table Heavy transmission interval. Preferably, the frame structure comprises at least one of the following: system bandwidth, fast Fourier transform FFT points, number of downlink subframes per frame, number of uplink subframes per frame, total number of subframes per frame, number of symbols per frame, and cyclic prefix of symbols CP length. Preferably, the maximum number of retransmissions includes the maximum number of retransmissions in the downlink and/or the maximum number of retransmissions in the uplink. Preferably, the signaling of the control channel comprises at least one of: signaling of a broadcast control channel SFH, signaling of a service control channel A-MAP channel, and signaling of a system configuration description SCD channel. According to another aspect of the present invention, a base station is provided, including: a setting module, configured to set a HARQ maximum retransmission interval according to a retransmission parameter, where the retransmission parameter includes a frame structure of a data frame and/or Or a maximum number of retransmissions; a sending module, configured to send a retransmission parameter to the terminal; and a retransmission module, configured to retransmit the data packet to the terminal according to the HARQ maximum retransmission interval. Preferably, the base station further includes: a signaling module, configured to determine, according to a HARQ maximum retransmission interval set by the setting module, control channel signaling sent on the control channel, where the control channel signaling includes retransmission interval indication information; The sending module is further configured to send control channel signaling to the terminal. According to another aspect of the present invention, a terminal is provided, including: a receiving module, configured to receive a retransmission parameter sent by a base station, where the retransmission parameter includes a frame structure of a data frame and/or a maximum number of retransmissions; And determining, by the retransmission parameter, a HARQ maximum retransmission interval, and a retransmission receiving module, configured to receive, according to a HARQ maximum retransmission interval, a data packet that is retransmitted by the base station. Preferably, the receiving module is further configured to receive the control channel signaling sent by the base station and send the signal to the determining module, where the control channel signaling includes retransmission interval indication information; the determining module is further configured to determine, according to the retransmission parameter and the control channel signaling HARQ maximum retransmission interval. According to another aspect of the present invention, a wireless communication system including the above-described base station and terminal is provided. The invention determines the HARQ maximum retransmission interval by using the retransmission parameter, so that when the base station and the terminal perform data retransmission, the maximum retransmission interval of the HARQ can be obtained through one signaling transmission, and no multiple transmission is needed, thereby effectively saving the letter. The overhead is simplified and the retransmission process is simplified. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, In the drawings: FIG. 1 is a schematic diagram of a radio frame structure of a related art; FIG. 2 is a schematic diagram of a frame structure of a radio communication system according to the related art; FIG. 3 is a data retransmission according to an embodiment of the present invention. FIG. 4 is a flow chart of steps of another data retransmission method according to an embodiment of the present invention; FIG. 5 is a structural block diagram of a base station according to an embodiment of the present invention; A structural block diagram of a terminal; FIG. 7 is a structural block diagram of a wireless communication system according to an embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. 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. Method Embodiment 1 Referring to FIG. 3, a flow chart of steps of a data retransmission method according to an embodiment of the present invention is shown, which includes the following steps: Step S302: The base station sets a HARQ maximum retransmission interval according to the retransmission parameter; The retransmission parameter includes a frame structure of the data frame and/or a maximum number of retransmissions, and may also include a resource scheduling situation, and a buffering situation of the base station and/or the terminal, where the situation of the base station mainly includes a resource scheduling tension of the base station, and the like. The cache condition refers to whether the terminal cache overflows or is about to overflow. For example, the base station sets according to the frame structure of the data frame and/or the maximum number of retransmissions, and the resource scheduling situation.

The HARQ maximum retransmission interval is 7 subframes. Step S304: The base station determines the control channel signaling sent on the control channel according to the HARQ maximum retransmission interval, where the control channel signaling includes retransmission interval indication information. For example, the base station may correspond to one or more retransmission relationship tables, and each retransmission relationship table corresponds to one or more retransmission parameters, where the retransmission relationship table includes a HARQ maximum retransmission interval and control channel signaling. The retransmission interval indicates the correspondence of the information. The base station selects a retransmission relationship table according to the retransmission parameter, and searches for the retransmission interval indication information corresponding to the HARQ maximum retransmission interval, and further determines the control channel signaling. Step S306: The base station sends the retransmission parameter and the control channel signaling to the terminal. Step S308: The terminal determines the HARQ maximum retransmission interval according to the retransmission parameter and the control channel signaling. For example, the terminal stores the same retransmission relationship as the base station. a table, the terminal determines a retransmission relationship table by using a retransmission parameter, and searches for a retransmission interval indication information corresponding to the control channel signaling.

The maximum retransmission interval of the HARQ, and the corresponding HARQ maximum retransmission interval is used as the retransmission of the current data. HARQ maximum retransmission interval. For example, when the maximum retransmission number T ReTx Interval is 4 and the system bandwidth is 5 MHz, the retransmission interval indication information in the control signaling SCD is the relationship between the N_SCD value and the maximum retransmission interval MAX Interval, as in the retransmission relationship table 1.1. Shown, where a is an integer greater than or equal to zero. The unit of the maximum retransmission interval MAX_Interval can be a subframe, a frame or a superframe, or a specific time such as seconds, milliseconds, microseconds, etc. The maximum retransmission interval MAX_Interval refers to the same, no longer - praise. Table 1.1

When the maximum number of retransmissions T ReTx Interval is 4 and the system bandwidth is 10 MHz, the retransmission interval indication information in the control signaling SCD is the relationship between the value of the N_SCD and the maximum retransmission interval MAX_Interval, as shown in the retransmission relationship table 1.2. Where b is an integer greater than or equal to zero. Table 1.2

When the maximum number of retransmissions T ReTx Interval is 4 and the system bandwidth is 20 MHz, the retransmission interval indication information in the control signaling SCD is the relationship between the value of N_SCD and the maximum retransmission interval MAX_Interval, as shown in Table 1.3, where c is An integer greater than or equal to 0. Table 1.3

Similarly, when T_ReTx_Interval is 8, the system bandwidth is 5MHZ, 10MHZ, 20MHZ can also get a table similar to Table 1.1 - Table 1.3, except that the parameters in the table are changed to d, e, f, no longer - Listed. Where a, b, c, d, e, f may be equal or unequal to each other. The retransmission relationship table used in such different system bandwidths and maximum retransmission times may be partially different, completely different, or identical. It should be noted that the above-mentioned retransmission relationship table is an exemplary description, and the actual application in the actual application can be flexibly set according to the actual situation, which is not limited by the present invention. Step S310: The terminal and the base station retransmit the data packet according to the HARQ maximum retransmission interval. After the terminal and the base station determine the HARQ maximum retransmission interval, the base station and the terminal follow the

The HARQ maximum retransmission interval retransmits the data packet.

In the HARQ related technology, since the correspondence between the binary parameter MAX_Interval transmitted using the control channel and the specific time is uncertain, additional signaling is needed to explicitly inform the terminal of the exact value of the parameter, so when the HARQ is retransmitted, the maximum retransmission time interval is notified. The signaling overhead is large. In this embodiment, the terminal only needs to know the explicit value of the maximum retransmission interval of the HARQ according to the retransmission parameters of the base station and the signaling of the control channel, which effectively saves the signaling overhead and simplifies the retransmission process. Method Embodiment 2 In this embodiment, the base station first determines the HARQ maximum retransmission interval according to the retransmission parameter, that is, the frame structure of the data frame and/or the maximum number of retransmissions, and determines the control channel according to the HARQ maximum retransmission interval. The control channel signaling sent on, in this embodiment, is an SCD, and the SCD and the retransmission parameters are sent together to the terminal. The base station sends retransmission interval indication information T_ReTx_Interval in SCD or other indication signaling In order to inform the value of the terminal MAX_Interval, but the terminal does not only specify the value of MAX_Interval according to the SCD terminal signaling T ReTx Interval, but also needs to determine the corresponding situation according to the frame structure and DL_N_MAX_ReTx and UL N MAX ReTx in the SFH. The maximum retransmission interval. For example, the system bandwidth is set to 5 MHz, the total number of subframes is F=5, the base value of the HARQ retransmission interval is 3, and the retransmission offset corresponding to F=5 is 1, T_ReTx_Interval takes 0-7, and the corresponding MAX Interval is T_ReTx_Interval. The value of the HARQ retransmission interval is the sum of 3 and the retransmission offset, that is, the time of 4 frames - 11 frames. For example, the system bandwidth is 20 MHz, the total number of subframes is F=5, the base value of the HARQ retransmission interval is 3, and the retransmission offset corresponding to F=5 is 0, the T ReTx Interval takes 0-7, and the corresponding MAX_Interval is 3 frames - 10 frames of time. In order to consider at least one or a combination of various factors, the value of MAX_Interval can be expressed by a formula, including but not limited to: indication signaling N_SCD in SCD, frame structure, downlink maximum retransmission times DL N MAX ReTx The maximum number of uplink retransmissions UL N MAX ReTx, wherein the frame structure includes at least: bandwidth (or FFT points), total number of subframes F, and total number of downlink subframes D. Formulaize the value of MAX_Interval as:

MAX Interval = x+NS CD+N FrameStr+N NumReTx ( 1 ) where MAX_Interval is the sub-frame; x is an integer greater than or equal to 0, indicating the base value of the MAX Interval value; N_SCD is the indication notified in the SCD Signaling T ReTx Interval size, the range is 0 7; N NumReTx is equal to a when DL N MAX ReTx = 4, equal to 0 when DL_N_MAX_ReTx = 8, a is an integer greater than or equal to 0; N FrameStr refers to the frame structure pair The effect of MAX_Interval, the value of N_FrameSt is determined according to Table 2.1 or 2.2, and N is a natural number, a is an integer greater than or equal to 0, floor (Y) represents the largest integer less than or equal to Y, and Y is any real number. Table 2.1

Table 2.2

The base station informs the terminal of the value of the MAX Interval by using the indication signal T ReTx Interval, but the terminal also needs to determine the specific value of the MAX_Interval according to the frame structure and the maximum number of retransmissions. Or the correspondence between the signaling T_ReTx_Interval and the parameter MAX Interval is determined by the frame structure and the maximum number of retransmissions. The correspondence between the signaling T ReTx Interval and the parameter MAX Interval in different cases is shown in equation (1). Method Embodiment 3 In this embodiment, the base station sends a signaling T ReTx Interval in the SCD or other indication signaling to notify the value of MAX_Interval, but not only the value of MAX_Interval is specified according to the SCD terminal signaling T ReTx Interval, but also needs to be According to DL N MAX ReTx and UL N MAX ReTx in SFH, the maximum retransmission interval corresponding to different situations is determined, but the influence of frame structure is not considered. For example, when the maximum number of retransmissions T ReTxJnterval is 4, the value of MAX_Interval is different from the maximum number of retransmissions T ReTx Interval is 8. The value of MAX Interval varies with the value N_SCD in the signaling SCD, and is also the largest. The number of retransmissions is related to T ReTx Interval. For example, as shown in Table 3.1, where N is a natural number, a is an integer greater than or equal to 0, floor(Y) represents the largest integer less than or equal to Y, and Y is any real number. Form 3.1

Method Embodiment 4 Referring to FIG. 4, a flow chart of steps of another data retransmission method according to an embodiment of the present invention is shown, including the following steps: Step S402: The base station sets the HARQ maximum according to the retransmission parameter. Retransmission interval; wherein, the retransmission parameter includes a frame structure of the data frame and/or a maximum number of retransmissions. For example, the base station may set a retransmission relationship table. In the table, the base station first sets a basic value of the HARQ retransmission interval, and then sets a retransmission offset according to the frame structure of the data frame, and bases the HARQ retransmission interval on the basic value and retransmits. The sum of the offsets is the HARQ maximum retransmission interval, corresponding to one retransmission parameter. Step S404: The base station sends the retransmission parameter to the terminal. Step 4: S406: The terminal determines the HARQ maximum retransmission interval according to the retransmission parameter. For example, the terminal stores the same retransmission relationship table as the base station, and the terminal may select And finding the maximum HARQ retransmission interval corresponding to the retransmission parameter in the retransmission relationship table, as the maximum HARQ retransmission interval of the current data retransmission. Step S408: The terminal and the base station retransmit the data packet according to the HARQ maximum retransmission interval. Method Embodiment 5 In this embodiment, the base station first sets a HARQ maximum retransmission interval according to the retransmission parameter, and then sends the retransmission parameter to the terminal, and the terminal determines the HARQ maximum retransmission interval. The base station does not notify the value of the HARQ maximum retransmission interval MAX_Interval in the SCD (System Configuration Descriptor) or other indication signaling, but only according to the frame structure and/or the downlink in the SFH (Superframe Header). The maximum number of retransmissions DL_N_MAX_ReTx, and/or the maximum number of retransmissions UL N MAX ReTx are determined. The content of the frame structure includes at least one or a combination of the following: system bandwidth, FFT points, number of downlink subframes per frame, number of uplink subframes per frame, total number of subframes per frame, number of symbols per frame, and symbols (CP Cyclic Prefix, Cyclic prefix) length, etc. The value of MAX_Interval is the same or different when different frame structures are specified. In this embodiment, the present invention is described by taking only the total number of subframes per frame as an example. Those skilled in the art can refer to this embodiment to set the maximum interval of HARQ retransmission using the above other frame structure. The above frame structure is a frame structure common in the related art, and the HARQ weight is determined according to the above frame structure. The maximum interval is transmitted, and the technical characteristics of the related technologies are utilized, and the implementation cost is saved on the basis of fully considering the related technologies. Because when the system bandwidth is large (or the system FFT points are large) or the system subframe number is large, the corresponding base station and terminal process more data, so that the cache buffer of the system and the terminal is insufficient, and the value of MAX_Interval should be more small. For example, it may be specified that the value of MAX_Interval is determined according to the bandwidth (the number of FFT points) and the total number of subframes, and the value of MAX Interval is defined by using the configuration in the retransmission relationship table 5.1. The unit of MAX Interval is a subframe, where F represents the number of subframes ( It can also be the corresponding number of milliseconds. X is the base value of the HARQ retransmission interval, which is a natural number: Table 5.1

As can be seen from the above table, in this embodiment, the retransmission offset is set according to the total number of subframes, when the system bandwidth is

At 20MHZ, the retransmission offset is set to an integer from 0 to 3 according to F. When the system bandwidth is 10MHZ, the retransmission offset is set to an integer from 1 to 4 according to F. When the system bandwidth is 5 MHz, the retransmission offset is set to an integer of 2 to 5, respectively. The larger the total number of subframes, the smaller the retransmission offset, and vice versa. The larger the system bandwidth, the smaller the corresponding retransmission offset setting, and vice versa. In practical applications, those skilled in the art can refer to Table 5.1 and set the retransmission offset according to the actual situation to set the value of MAX_Interval. Through the setting method shown in the above table, the terminal can learn the HARQ maximum retransmission interval when the base station retransmits the data frame, and the frame structure of the data frame can be obtained. The implementation is simple and the signaling overhead is small. For another example, it may be specified that the value of MAX_Interval is determined according to the bandwidth (the number of FFT points) and the total number of subframes, but the value of MAX_Interval may not be incremented by every other level, and the value of MAX Interval may be 4 B every N levels. Add one, use the table in the retransmission relationship table 5.2 to define the value of MAX_Interval, the unit of MAX Interval is the subframe, where x is the base value of the HARQ retransmission interval, which is a natural number, N is also a natural number, and indicates the level. a is an integer greater than or equal to 0, floor(Y) represents the largest integer less than or equal to Y, and Y is any real number: Table 5.2

For another example, optimize based on Table 5.2. Table 5.2 is used when the maximum number of downlink retransmissions indicated in SFH is DL N MAX ReTx = 4. When DL_N_MAX_ReTx = 8, Table 5.3 is used, where b is less than or equal to Integer a: Table 5.3

At the same time, considering that the parameter MAX Interval is only about the downlink HARQ parameters, regardless of the uplink, the total number of subframes in the table of Tables 5.1-5.3 can be changed to the total number of downlink subframes D, so that only the amount of downlink data is considered, and Table 5.4 is obtained. -5.6: Table 5.4

Table 5.5

Table 5.6

It should be noted that the specific numerical values in this embodiment are all examples, such as

When DL N MAX ReTx = 4, use Table 5.2, DL N MAX ReTx = 8, use Table 5.3, and the total number of sub-frames F in each table, etc., in actual use, those skilled in the art can appropriately set according to the actual situation. The invention is not limited thereto. For the determination of the maximum retransmission interval when considering the maximum number of retransmissions as shown in Table 5.3-5.6, the basic principle is that the more retransmission times, the shorter the maximum retransmission interval is set. In addition, when the value of the parameter MAX_Interval is determined by the method of the foregoing multiple embodiments, when the interval between two retransmissions is greater than MAX_Interval, the terminal considers that the transmission fails and performs packet loss processing. The end of the biography. Alternatively, the value of the parameter MAX_Interval is determined by the method in this embodiment. However, when determining whether the maximum retransmission interval is reached, the terminal not only determines whether the interval between two retransmissions exceeds MAX Interval, but also determines the remaining retransmission. frequency. For example, when the maximum number of downlink retransmissions DL N MAX ReTx = 4, the first transmission fails, and there are three retransmissions. The terminal ^ ¹ waits for the interval of MAX_Intervalx3. If no retransmission packet is received, the packet loss is judged. . If the first transmission fails, one retransmission is unsuccessful, and there are two retransmissions. The terminal will wait for the interval of MAX_Interval 2. If no retransmission packet is received, it will judge the packet loss. If the first transmission fails, two retransmissions are unsuccessful, and there is one retransmission. The terminal will wait for the interval of MAX_Interval. If no retransmission packet is received, it will judge the packet loss. Apparatus Embodiment Referring to FIG. 5, a block diagram of a base station according to an embodiment of the present invention is shown, including: a setting module 502, configured to set a HARQ maximum retransmission interval according to a retransmission parameter, where the retransmission parameter includes data. The frame structure of the frame and/or the maximum number of retransmissions; the sending module 504 is configured to send the retransmission parameter to the terminal, and the retransmission module 506 is configured to retransmit the data packet to the terminal according to the HARQ maximum retransmission interval. Preferably, the base station further includes a signaling module, configured to determine, according to a HARQ maximum retransmission interval set by the setting module 502, control channel signaling sent on the control channel, where the control channel signaling includes retransmission interval indication information. The sending module 504 is further configured to send the control channel signaling to the terminal. Preferably, the frame structure comprises at least one of the following: system bandwidth, fast Fourier transform FFT points, number of downlink subframes per frame, number of uplink subframes per frame, total number of subframes per frame, number of symbols per frame, and symbols a cyclic prefix CP length; the maximum number of retransmissions includes a downlink maximum retransmission number and/or an uplink maximum retransmission number; the signaling of the control channel includes at least one of: signaling of a broadcast control channel SFH, A-MAP The signaling of the channel, and the system configuration describe the signaling of the SCD channel. Referring to FIG. 6, a structural block diagram of a terminal according to an embodiment of the present invention is shown, including: a receiving module 602, configured to receive a retransmission parameter sent by a base station, where the retransmission parameter includes a frame structure of a data frame, and And a maximum number of retransmissions; a determining module 604, configured to determine a HARQ maximum retransmission interval by using the retransmission parameter; and a retransmission receiving module 606, configured to receive, according to a HARQ maximum retransmission interval, a data packet retransmitted by the base station. Preferably, the receiving module 602 is further configured to receive the control channel signaling sent by the base station and send the signal to the determining module 604, where the control channel signaling includes retransmission interval indication information. The determining module 604 is further configured to determine a HARQ maximum retransmission interval according to the retransmission parameter and the control channel signaling. Preferably, the frame structure comprises at least one of the following: system bandwidth, fast Fourier transform FFT points, number of downlink subframes per frame, number of uplink subframes per frame, total number of subframes per frame, number of symbols per frame, and symbols a cyclic prefix CP length; the maximum number of retransmissions includes a downlink maximum retransmission number and/or an uplink maximum retransmission number; the signaling of the control channel includes at least one of: signaling of a broadcast control channel SFH, A-MAP The signaling of the channel, and the system configuration describe the signaling of the SCD channel. Referring to FIG. 7, a structural block diagram of a wireless communication system according to an embodiment of the present invention is shown, including: a base station 702 and a terminal 704. The base station 702 includes a setting module 7022, configured to determine a HARQ maximum retransmission interval according to the retransmission parameter, where the retransmission parameter includes a frame structure of the data frame and/or a maximum number of retransmissions, and a sending module 7024, configured to The retransmission parameter is sent to the terminal; the retransmission module 7026 is configured to retransmit the data packet to the terminal according to the HARQ maximum retransmission interval. Preferably, the base station 702 further includes a signaling module, configured to be configured according to the setting module 7022.

The HARQ maximum retransmission interval determines control channel signaling transmitted on the control channel, and the control channel signaling includes retransmission interval indication information. The sending module 7024 is further configured to send the control channel signaling to the terminal. The terminal 704 includes a receiving module 7042, configured to receive a retransmission parameter sent by the base station 702, where the retransmission parameter includes a frame structure of the data frame and/or a maximum number of retransmissions, and a determining module 7044, configured to retransmit the data. The parameter determines the HARQ maximum retransmission interval; the retransmission receiving module 7046 is configured to receive the data packet retransmitted by the base station according to the HARQ maximum retransmission interval. Preferably, the receiving module 7042 is further configured to receive the control channel signaling sent by the base station 702 and send the signal to the determining module 7044, where the control channel signaling includes retransmission interval indication information. The determining module 7044 is further configured to determine the HARQ maximum retransmission interval according to the retransmission parameter and the control channel signaling. Preferably, the frame structure includes at least one of the following: a system bandwidth, a fast Fourier transform FFT point number, a number of downlink subframes per frame, an uplink subframe number per frame, a total number of subframes per frame, a symbol number per frame, and a symbol cycle. a prefix CP length; the maximum number of retransmissions includes a downlink maximum retransmission number and/or an uplink maximum retransmission number; and the signaling of the control channel includes at least one of: a signaling of a broadcast control channel SFH, and an A-MAP channel. The signaling, and system configuration describes the signaling of the SCD channel. 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 and, in some cases, may be different from the order herein. The steps shown or described are performed, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps are fabricated as 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. Where in the invention ^" God and Within the principles, any modifications, equivalent substitutions, improvements, etc., are intended to be included within the scope of the present invention.

Claims

Claims A data retransmission method, characterized in that it comprises:

The base station sets a HARQ maximum retransmission interval according to the retransmission parameter, where the retransmission parameter includes a frame structure of the data frame and/or a maximum number of retransmissions;

Determining, by the base station, the control channel signaling sent on the control channel according to the HARQ maximum retransmission interval, where the control channel signaling includes retransmission interval indication information;

Sending, by the base station, the retransmission parameter and the control channel signaling to the terminal;

Determining, by the terminal, the HARQ maximum retransmission interval according to the retransmission parameter and control channel signaling;

The terminal and the base station retransmit the data packet at the HARQ maximum retransmission interval. The method according to claim 1, wherein the determining, by the base station, the control channel signaling sent on the control channel according to the HARQ maximum retransmission interval comprises:

The base station selects a retransmission relationship table according to the retransmission parameter, where the retransmission relationship table includes a correspondence between the HARQ maximum retransmission interval and the retransmission interval indication information; The retransmission relationship table searches for the retransmission interval indication information corresponding to the HARQ maximum retransmission interval, and determines the control channel signaling. The method according to claim 2, wherein the correspondence between the HARQ maximum retransmission interval and the retransmission interval indication information is determined by:

And the base station sets a retransmission offset according to the retransmission parameter, where the retransmission offset is an integer greater than or equal to 0;

And the base station sets the retransmission interval indication information, the sum of the HARQ retransmission interval base value, and the retransmission offset to be equal to the HARQ maximum retransmission interval. The method according to claim 2, wherein the step of determining, by the terminal, the HARQ maximum retransmission interval according to the retransmission parameter and the control channel signaling comprises:

Determining, by the terminal, the retransmission relationship table stored by the terminal according to the retransmission parameter; the terminal determining retransmission interval indication information from the control channel signaling from the selected retransmission relationship table Corresponding HARQ maximum retransmission interval.

The method according to claim 1, wherein the frame structure comprises at least one of: system bandwidth, fast Fourier transform FFT points, number of downlink subframes per frame, number of uplink subframes per frame, each frame The total number of subframes, the number of symbols per frame, and the cyclic prefix CP length of the symbol.

The method according to claim 1, wherein the maximum number of retransmissions includes a maximum number of downlink retransmissions and/or an uplink maximum retransmission number.

The method according to claim 1, wherein the signaling of the control channel comprises at least one of: signaling of a broadcast control channel SFH, signaling of a service control channel A-MAP channel, and system configuration. Describe the signaling of the SCD channel.

8. A data retransmission method, characterized in that:

Sending, by the base station, the retransmission parameter to a terminal;

And determining, by the terminal, the retransmission parameter to determine the HARQ maximum retransmission interval; and the terminal and the base station retransmit the data packet in the HARQ maximum retransmission interval.

The method according to claim 8, wherein the step of the base station setting the HARQ maximum retransmission interval according to the retransmission parameter comprises:

The base station reads the retransmission relationship table according to the retransmission parameter, where the retransmission relationship table includes a correspondence between the retransmission parameter and the maximum retransmission interval of the HARQ;

Determining, by the base station, the HARQ maximum retransmission interval corresponding to the retransmission parameter from the retransmission relationship table.

The method according to claim 9, wherein the correspondence between the retransmission parameter and the HARQ maximum retransmission interval is determined by:

The base station sets a retransmission offset according to the retransmission parameter;

The base station sets the sum of the retransmission offset and the HARQ retransmission interval base value to be a HARQ maximum retransmission interval corresponding to the retransmission parameter.

11. The method according to claim 10, wherein the determining, by the terminal, the step of determining the maximum retransmission interval of the HARQ according to the retransmission parameter comprises:

The terminal reads the retransmission relationship table stored by the terminal according to the retransmission parameter; Determining, by the terminal, the HARQ maximum retransmission interval corresponding to the retransmission parameter from the retransmission relationship table.

12. The method of claim 8, wherein the frame structure comprises at least one of: system bandwidth, fast Fourier transform FFT points, number of downlink subframes per frame, number of uplink subframes per frame, each frame The total number of subframes, the number of symbols per frame, and the cyclic prefix CP length of the symbol.

The method according to claim 8, wherein the maximum number of retransmissions includes a maximum number of downlink retransmissions and/or an uplink maximum retransmission number.

The method according to claim 8, wherein the signaling of the control channel comprises at least one of: signaling of a broadcast control channel SFH, signaling of a service control channel A-MAP channel, and system configuration. Describe the signaling of the SCD channel.

15. A base station, comprising:

a setting module, configured to set a HARQ maximum retransmission interval according to the retransmission parameter, where the retransmission parameter includes a frame structure of the data frame and/or a maximum number of retransmissions;

a sending module, configured to send the retransmission parameter to the terminal;

And a retransmission module, configured to retransmit the data packet to the terminal at the maximum HARQ retransmission interval.

The base station according to claim 15, further comprising:

a signaling module, configured to determine, according to the HARQ maximum retransmission interval set by the setting module, control channel signaling sent on a control channel, where the control channel signaling includes retransmission interval indication information;

The sending module is further configured to send the control channel signaling to the terminal.

17. The base station according to claim 16, wherein

The frame structure includes at least one of the following: system bandwidth, fast Fourier transform FFT points, number of downlink subframes per frame, number of uplink subframes per frame, total number of subframes per frame, number of symbols per frame, and cyclic prefix CP of symbols Length

The maximum number of retransmissions includes a maximum number of downlink retransmissions and/or an uplink maximum retransmission number. The signaling of the control channel includes at least one of: signaling of a broadcast control channel SFH, and a service control channel A-MAP channel. Signaling, and system configuration describe the signaling of the SCD channel.

18. A terminal, characterized by comprising:

a receiving module, configured to receive a retransmission parameter sent by the base station, where the retransmission parameter includes a frame structure of the data frame and/or a maximum number of retransmissions;

And a determining module, configured to determine a HARQ maximum retransmission interval by using the retransmission parameter, and a retransmission receiving module, configured to receive, according to the HARQ maximum retransmission interval, a data packet that is retransmitted by the base station.

The terminal according to claim 18, wherein the receiving module is further configured to receive control channel signaling sent by the base station and send the signaling to the determining module, where the control channel signaling includes retransmission interval indication information. ;

The determining module is further configured to determine the HARQ maximum retransmission interval according to the retransmission parameter and the control channel signaling.

20. The terminal of claim 19, wherein

A wireless communication system, comprising:

A base station according to any one of claims 15 to 17;

A terminal according to any one of claims 18 to 20.