CN102124685B - A self-adapting HARQ method, apparatus and device - Google Patents

Abstract

A self-adapting HARQ method, apparatus and device are provided by the embodiments of this invention. A receiving end receives the data packet, and feeds the different message to the transmitting end self-adaptively according to the detecting condition of the date packet and the reception times. The transmitting end selects a retransmitting scheme self-adaptively according to the retransmitting times and the received feedback message, if it is the first time to retransmit, the data packet is retransmitted to the receiving end by using HARQ technology which is based on STBC, wherein, the retransmitting data packet and the first transmitted data packet form a STBC code word; if it is the second time to retransmit or more times retransmission, the data packet is retransmitted by using HARQ technology which is based on the closed loop MIMO system, wherein, a pre-encode matrix is selected according to the feedback pre-encode matrix index, the data packet that will be transmitting in this time is pre-encoded, then is retransmitted to the receiving end. Wherein, pre-encode matrix is calculated according to the result of unitedly optimizing the received data packet and the data packet that will be received at the next time, and the pre-encoded matrix index is fed back to the transmitting end. By applying the self-adapting HARQ scheme of this invention, the time diversity gain and the total space diversity gain can be obtained, the delay of the system can be reduced, the throughput of the MIMO system can be improved, and it can split the difference between the performance and the complexity.

Description

The method of adaptive HARQ, device and equipment

Technical field

The present invention relates to the communication technology, particularly relate to the method for adaptive HARQ, device and equipment.

Background technology

In a wireless communication system, MIMO (mimo antennas technology) system is used to provide spatial reuse to improve point-to-point link capacity, but due to the deep fade of time varying channel, disturb between a large amount of noises and cochannel, receiving terminal correctly can not recover the packet of transmission, and therefore the extensive use of mixed automatic retransfer HARQ technology merges decoding error packet and retransmission data packet may to strengthen the reliability of data packet transmission.

At present many HARQ transmission technology being applied to mimo system are proposed.In traditional simple repetition transmitting HARQ scheme, transmitting terminal is by two or many antenna transmissions at least 2 packets.If the packet launched is not correctly received, then loses the packet of the initial transmission received at receiving terminal, and at retransmission phase, simply repeat to send this packet.Table 1 illustrates the data package retransmission method according to the simple HARQ scheme of tradition in two transmit antennas and two reception antenna systems, and wherein S1 and S2 is the packet be launched.Use the method, first time has retransmitted a repeated encoding process, correspondingly can obtain partial diversity gain.Because simply repeat transmission can not obtain full diversity gains, the reliability of re-transmission can not get strengthening, and Time Delay of Systems is corresponding can be increased.

Table 1

For obtaining whole diversity gains and retransmission scheme is simple, list of references 1:Elisabeth de Carvalho and Petar Popovski; " Strategies for ARQ in 2 × 2 MIMO Systems; " IEEE communications letters, vol.12, no.6, June 2008, pp.441-443 proposes the HARQ retransmission technique based on STBC, wherein retransmission data packet may keeps identical data, and allows the change of data symbol, Data Conjugate change and the change of antenna assignment.Obviously, this twice re-transmission forms a STBC code word (based on packet).Table 2 gives the data packet retransmission scheme based on the HARQ of STBC in 2 × 2MIMO system.Wherein in the first stage, packet S ₁launch and S from antenna 1 ₂launch from antenna 2.If two data all occur mistake when wrapping in decoding, then at second stage, exchange antenna assignment namely ,-S ₂ ^*retransmit from antenna 1, S ₁ ^*retransmit from antenna 2, then the packet of receiving terminal twice reception forms STBC group, adopts STBC to have decoded the recovery of packet.If at this moment still made a mistake during decoded packet data, retransmit for the second time and still send raw data packets to form a STBC code word together with the packet retransmitted for the first time, the 3rd this re-transmission then sends the packet of first time re-transmission, so analogizes.The full diversity gains produced due to STBC and antenna array gain can resist channel fading, and each re-transmission can improve the probability that packet correctly receives.But, if decoding error is disturbed by cochannel to cause, then adopt the correct reception reliability of this retransmission scheme to reduce.

Table 2

For the reception mistake that antagonism intra-cell interference and presence of intercell interference cause, HARQ technology based on closed-loop MIMO system is suggested to reduce interference, its general principle is, channel information according to receiving calculates a pre-coding matrix and feeds back this precoding matrix information, each re-transmission, transmitting terminal uses the pre-coding matrix of feedback to carry out precoding to data retransmission, makes re-transmission obtain diversity gain; Meanwhile, receiving terminal, according to given re-transmission merging type, if Chase Merge Scenarios and incremental redundancy Merge Scenarios etc. are to maximally utilise the multichannel MIMO signal received.List of references 2:Byung-Jae Kwak, Dong SeungKwon, et.Al., " HARQ in a Closed Loop MIMO System ", ETRI, IEEEC802.16m-08/440 propose a kind of HARQ scheme of closed-loop MIMO system, in the program, first select the packet of a Linear precoding matrix to transmission to carry out precoding when retransmitting at every turn, merge the data that repeatedly retransmit at receiving terminal to obtain higher merging gain to improve decoding probability.Fig. 1 provides the enforcement structural representation of closed-loop MIMO system HARQ scheme, and wherein S is packet vector, and WL is pre-coding matrix.The Received signal strength retransmitted for the l time is

r _l＝H _lW _lS+n _l(1)

Wherein H _lbe the mimo channel matrix of the l time transmission, L is maximum transmission times, and n is noise.Retransmit through L-1 time, the data that receiving terminal repeatedly receives can be expressed as in cascade:

$r=\left[\begin{array}{c}{r}_1\\ r_2\\ \·\\ \·\\ \·\\ r_L\end{array}\right]=\left[\begin{array}{c}{H}_1{W}_1\\ H_1{W}_1\\ \·\\ \·\\ \·\\ H_L{W}_L\end{array}\right]S+\left[\begin{array}{c}{n}_1\\ n_2\\ \·\\ \·\\ \·\\ n_L\end{array}\right]---\left(2\right)$

Through the merging treatment of symbol level, merge gain obtained to reduce intra-cell interference and interval interference, then the corresponding correct probability receiving packet increases.But due to channel time-varying characteristics, each re-transmission need according to channel estimation calculation pre-coding matrix W, and program computation complexity is too high so that be difficult to application in systems in practice.

Summary of the invention

For solving above-mentioned shortcoming of the prior art, the present invention proposes new adaptive HARQ method, device and equipment.Receiving terminal receives packet, and according to packet detection case with receive number of times, the different message of adaptive feedback is to transmitting terminal.Transmitting terminal is according to number of retransmissions and the feedback message received, adaptively selected retransmission scheme, if first time retransmits, with the HARQ technology retransmission data packet may based on STBC to receiving terminal, the packet that described retransmission data packet may and first time send forms a STBC code word; If second time and more high order retransmit, select with the HARQ technology retransmission data packet may based on closed-loop MIMO system, according to the pre-coding matrix index of feedback, select pre-coding matrix, retransmit to receiving terminal after precoding is carried out to the packet of this transmission.Wherein, pre-coding matrix is according to calculate after the packet combined optimization packet received and next time retransmitting reception and by this precoding matrix index feedback to transmitting terminal by receiving terminal.

Further, the present invention also proposes a combined optimization algorithm, channel condition information when channel condition information when receiving terminal is transmitted by the former secondary data bag of associating and current data packet transmission calculates the weights of global optimization and the pre-coding matrix of global optimization, re-transmission is made to obtain larger diversity gain, to resist the interference with minizone in community.Concrete, based on maximum S/N R criterion, the pre-coding matrix of calculation optimization.Be about to the packet that received and retransmit next time the packet of reception to combine carry out symbol level merging, export signal to noise ratio SNR criterion after maximization symbol level merges under, calculate pre-coding matrix.

The present invention merges the symbol level of receiving terminal and is also optimized further, by the front packet received several times respectively cancellation decode after correct packet and carry out symbol level merging with this packet received, carry out combined decoding after symbol level merging.Equally, the optimization that symbol level merges also can be applicable in combined optimization algorithm, be about to the packet that received respectively cancellation decoded after correct packet and retransmitted next time the packet of reception to combine and carried out symbol level merging, maximize export the criterion of signal to noise ratio SNR after symbol level merges under calculate pre-coding matrix.

In addition, also can incorporating selectively retransmit in the present invention, namely receiving terminal is according to decoding cases, decode error information is fed back to transmitting terminal, and transmitting terminal is according to decode error information, and the packet of selective decompression mistake is as retransmission data packet may, and send together with new data packets, to increase throughput.

Particularly, according to an embodiment of the invention, provide a kind of adaptive HARQ method, the method comprises: transmitting terminal sends packet; Receiving terminal reception packet, judges to receive number of times, according to reception number of times determination data packet inspection method, and feeds back different message to transmitting terminal according to packet testing result and reception number of times; Transmitting terminal receives feedback message, determines retransmission scheme and retransmit content according to feedback message and number of retransmissions.

According to an embodiment of the present invention, receiving terminal judges to receive number of times, comprises: if receiving number of times is 0, directly decode to reception packet according to reception number of times determination data packet inspection method; Otherwise the packet of this reception and the front packet received several times are combined after symbol level merges and decodes.

According to an embodiment of the present invention, the packet that this is received and the front packet received several times after symbol level merge, combine that carrying out decodes refer to by the front packet received several times respectively cancellation decode after correct packet and carry out symbol level merging with this packet received, combine after symbol level merging and decode.

According to an embodiment of the present invention, feed back different message according to packet testing result and reception number of times and comprise to transmitting terminal:

If decoded packet data is correct, feed back ACK (affirmative acknowledgement) message to transmitting terminal, receive number of times and be set to 0; If decoded packet data mistake, judge

If receive number of times to reach a set point, feed back NAK (negative response) message to transmitting terminal, receive number of times and be set to 0;

If receive number of times be less than a set point, then store the packet of reception, reception number of times is added 1 and,

If receiving number of times is 1, receiving terminal sends a NAK message to transmitting terminal; If receive number of times to be greater than 1, then calculate a pre-coding matrix and feed back this pre-coding matrix index and a NAK message to transmitting terminal.

According to an embodiment of the present invention, if comprise decoded packet data mistake further according to packet testing result and reception number of times, receive number of times and be less than a set point, receiving terminal also sends a packet decode error information to transmitting terminal.

According to an embodiment of the present invention, transmitting terminal determines retransmission scheme according to feedback message and number of retransmissions and retransmits content to comprise:

If receive ACK message, send new data packets, number of retransmissions is set to 0;

If receive NAK message, number of retransmissions is added 1 and judges number of retransmissions: if number of retransmissions is 1, using the packet that the packet of first time transmission transmits as this, and with the HARQ technology retransmission data packet may based on STBC to receiving terminal, the packet that described retransmission data packet may and first time send forms a STBC code word;

If number of retransmissions is not more than a default value, using the packet that the packet of first time transmission transmits as this, and select pre-coding matrix according to the pre-coding matrix index in feedback message, retransmit to receiving terminal after precoding is carried out to the packet of this transmission;

If number of retransmissions is greater than a default value, sends new data packets, number of retransmissions is set to 0.

According to an embodiment of the present invention, further, the packet transmitted first time is need the packet retransmitted and the packet transmitted as this according to packet error Information Selection as this packet transmitted.

According to an embodiment of the present invention, the packet of this transmission comprises new data packets further.

According to an embodiment of the present invention, transmitting terminal is to refer to that based on the HARQ technology retransmission data packet may of STBC transmitting terminal sends the common strategic point of initial data packets.

According to an embodiment of the present invention, transmitting terminal is to refer to that based on the HARQ technology retransmission data packet may of STBC transmitting terminal sends the orthogonal sequence corresponding to initial data packets.

According to an embodiment of the present invention, described calculating pre-coding matrix is based on maximum S/N R criterion, calculates the pre-coding matrix of optimization.

According to an embodiment of the present invention, the packet received and next time are retransmitted the packet of reception to combine and carries out symbol level merging, under maximizing symbol level to merge the criterion of output signal-to-noise ratio SNR afterwards, calculate pre-coding matrix.

According to an embodiment of the present invention, the packet received and next time are retransmitted the packet of reception combined carry out symbol level merge refer to by the packet received respectively cancellation decoded after correct packet and carried out symbol level merging with retransmitting next time the packet of reception to combine.

According to an embodiment of the present invention, described set point refers to the maximum retransmission of default.

According to an embodiment of the invention, provide a kind of repeating method of adaptive HARQ, the method comprises: transmitting terminal sends packet, and transmitting terminal receives feedback message, determines retransmission scheme and retransmit content according to feedback message and number of retransmissions.

According to an embodiment of the present invention, transmitting terminal determines retransmission scheme according to feedback message and number of retransmissions and retransmits content to comprise:

If receive ACK message, send new data packets, number of retransmissions is set to 0;

If receive NAK message, number of retransmissions is added 1 and judges number of retransmissions: if number of retransmissions is 1, using the packet that the packet of first time transmission transmits as this, and with the HARQ technology retransmission data packet may based on STBC to receiving terminal, the packet that described retransmission data packet may and first time send forms a STBC code word;

If number of retransmissions is not more than a default value, using the packet that the packet of first time transmission transmits as this, and select pre-coding matrix according to the pre-coding matrix index in feedback message, retransmit to receiving terminal after precoding is carried out to the packet of this transmission;

If number of retransmissions is greater than a default value, sends new data packets, number of retransmissions is set to 0.

According to an embodiment of the present invention, further, the packet of first time transmission is referred to the packet retransmitted according to the packet error Information Selection needs in feedback message and the packet transmitted as this as the packet that this transmits.

According to an embodiment of the present invention, the packet of this transmission comprises new data packets further.

According to an embodiment of the present invention, transmitting terminal is to refer to that based on the HARQ technology retransmission data packet may of STBC transmitting terminal sends the common strategic point of the packet needing transmission.

According to an embodiment of the present invention, transmitting terminal is to refer to that based on the HARQ technology retransmission data packet may of STBC transmitting terminal sends the orthogonal sequence corresponding to the packet needing transmission.

According to an embodiment of the invention, provide a kind of reception feedback method of adaptive HARQ, the method comprises: receiving terminal receives described packet, judges to receive number of times, detects according to reception number of times determination data bag; And feed back different message to transmitting terminal according to packet testing result and reception number of times.

According to an embodiment of the present invention, receiving terminal judges to receive number of times, detects and comprises: if receiving number of times is 0, directly decode to reception packet according to reception number of times determination data bag; Otherwise the packet of this reception and the front packet received several times are combined after symbol level merges and decodes.

According to an embodiment of the present invention, the packet that this is received and the front packet received several times after symbol level merge, combine that carrying out decodes refer to by the front packet received several times respectively cancellation decode after correct packet and carry out symbol level merging with this packet received, combine after symbol level merging and decode.

According to an embodiment of the present invention, feed back different message according to packet testing result and reception number of times and comprise to transmitting terminal:

If decoded packet data is correct, feed back an ACK message to transmitting terminal, receive number of times and be set to 0;

If decoded packet data mistake, judge

If receive number of times to reach a set point, feed back a NAK message to transmitting terminal, receive number of times and be set to 0;

If receive number of times be less than a set point, then store the packet of reception, reception number of times is added 1 and,

If receiving number of times is 1, receiving terminal sends a NAK message to transmitting terminal;

If receive number of times to be greater than 1, then calculate a pre-coding matrix and feed back this pre-coding matrix index and a NAK message to transmitting terminal.

According to an embodiment of the present invention, if feed back different message according to packet testing result and reception number of times to comprise decoded packet data mistake further to transmitting terminal, receive number of times and be less than a set point, receiving terminal also sends a packet decode error information to transmitting terminal.

According to an embodiment of the present invention, calculating a pre-coding matrix is based on maximum S/N R criterion, calculates the pre-coding matrix of optimization.

According to an embodiment of the present invention, the packet received and next time are retransmitted the packet of reception to combine and carries out symbol level merging, under maximizing symbol level to merge the criterion of output signal-to-noise ratio SNR afterwards, calculate pre-coding matrix.

According to an embodiment of the present invention, the packet received and next time are retransmitted the packet of reception combined carry out symbol level merge refer to by the packet received respectively cancellation decoded after correct packet and carried out symbol level merging with retransmitting next time the packet of reception to combine.

According to an embodiment of the present invention, described set point refers to the maximum retransmission of default.

According to an embodiment of the invention, provide a kind of retransmission arrangement of adaptive HARQ, this device comprises: transmitting element, for sending packet; Receiving element, for receiving feedback message; Judging unit, for judging feedback message and number of retransmissions; Processing unit, for determining retransmission scheme according to feedback message and number of retransmissions and retransmitting content.

According to an embodiment of the present invention, determine retransmission scheme according to feedback message and number of retransmissions and retransmit content to comprise:

If receive ACK message, send new data packets, number of retransmissions is set to 0;

If receive NAK message, number of retransmissions is added 1 and judges number of retransmissions: if number of retransmissions is 1, using the packet that the packet of first time transmission transmits as this, and with the HARQ technology retransmission data packet may based on STBC to receiving terminal, the packet that described retransmission data packet may and first time send forms a STBC code word;

If number of retransmissions is not more than a default value, using the packet that the packet of first time transmission transmits as this, and select pre-coding matrix according to the pre-coding matrix index in feedback message, retransmit to receiving terminal after precoding is carried out to the packet of this transmission;

If number of retransmissions is greater than a default value, sends new data packets, number of retransmissions is set to 0.

According to an embodiment of the present invention, if receive NAK message, the packet of first time transmission is referred to the packet retransmitted according to the packet error Information Selection needs in feedback message and the packet transmitted as this as the packet that this transmits.

According to an embodiment of the present invention, the packet of this transmission comprises new data packets further.

According to an embodiment of the present invention, to refer to the common strategic point sending the packet needing transmission based on the HARQ technology retransmission data packet may of STBC.

According to an embodiment of the present invention, to refer to the orthogonal sequence sent corresponding to the packet needing transmission based on the HARQ technology retransmission data packet may of STBC.

According to an embodiment of the invention, provide a kind of reception feedback device of adaptive HARQ, this device comprises: receiving element, for receiving described packet; Judging unit, receives number of times and decoded packet data situation for judging; Data packet detecting unit unit, for detecting according to reception number of times determination data bag; Feedback unit, for feeding back different message according to packet testing result and reception number of times.

According to an embodiment of the present invention, detect according to reception number of times determination data bag and comprise: if receiving number of times is 0, directly reception packet is decoded; Otherwise the packet of this reception and the front packet received several times are combined after symbol level merges and decodes.

According to an embodiment of the present invention, the packet that this is received and the front packet received several times after symbol level merge, combine that carrying out decodes refer to by the front packet received several times respectively cancellation decode after correct packet and carry out symbol level merging with this packet received, combine after symbol level merging and decode.

According to an embodiment of the present invention, feed back different message according to packet testing result and reception number of times and comprise:

If decoded packet data is correct, feed back an ACK message, receive number of times and be set to 0;

If decoded packet data mistake, judge

If receive number of times to reach a set point, feed back a NAK message, receive number of times and be set to 0;

If receive number of times be less than a set point, then store the packet of reception, reception number of times is added 1 and,

If receiving number of times is 1, receiving terminal sends a NAK message;

If receive number of times to be greater than 1, then calculate a pre-coding matrix and feed back this pre-coding matrix index and a NAK message.

According to an embodiment of the present invention, if feed back different message according to reception number of times to comprise decoded packet data mistake further, receive number of times and be less than a set point, also send a packet decode error information.

According to an embodiment of the present invention, calculating a pre-coding matrix is based on maximum S/N R criterion, calculates the pre-coding matrix of optimization.

According to an embodiment of the present invention, the packet received and next time are retransmitted the packet of reception to combine and carries out symbol level merging, under maximizing symbol level to merge the criterion of output signal-to-noise ratio SNR afterwards, calculate pre-coding matrix.

According to an embodiment of the present invention, the packet received and next time are retransmitted the packet of reception combined carry out symbol level merge refer to by the packet received respectively cancellation decoded after correct packet and carried out symbol level merging with retransmitting next time the packet of reception to combine.

According to an embodiment of the present invention, described set point refers to the maximum retransmission of default.

According to an embodiment of the invention, a kind of network side equipment adopting adaptive HARQ is provided, comprises the retransmission arrangement of above-mentioned adaptive HARQ.

According to an embodiment of the invention, a kind of terminal equipment adopting adaptive HARQ is provided, comprises the retransmission arrangement of above-mentioned adaptive HARQ.

According to an embodiment of the invention, provide a kind of network side equipment adopting adaptive HARQ, comprise the reception feedback device of above-mentioned adaptive HARQ.

According to an embodiment of the invention, provide a kind of terminal equipment adopting adaptive HARQ, comprise the reception feedback device of above-mentioned adaptive HARQ.

The method that the application of the invention provides, device and equipment, according to the adaptively selected HARQ technology of number of retransmissions, and combined optimization pre-coding matrix weights, re-transmission is made to obtain time diversity gain and total space diversity gain, can system delay be reduced, improve the throughput of mimo system, and between performance and complexity, have a compromise preferably.

Accompanying drawing explanation

By below in conjunction with the description of the drawings, and understand more comprehensively along with to of the present invention, other objects of the present invention and effect will become clearly and easy to understand, wherein:

Fig. 1 represents the schematic block diagram of the HARQ scheme of closed-loop MIMO system.

Fig. 2 represents the HARQ scheme schematic flow sheet according to an embodiment of the invention, and maximum retransmission is 2.

Fig. 3 represents the HARQ scheme schematic flow sheet according to an embodiment of the invention, band packet error information.

Fig. 4 represents the indicative flowchart of the HARQ repeating method adopting an embodiment of the invention.

Fig. 5 represents that the HARQ according to an embodiment of the invention receives the indicative flowchart of feedback method.

Fig. 6 represents the structural schematic block diagram of the retransmission arrangement according to an embodiment of the invention.

Fig. 7 represents the structural schematic block diagram of the reception feedback device according to an embodiment of the invention.

Fig. 8 represents according to the throughput simulation result schematic diagram based on 2 × 2MIMO system of the present invention.

Fig. 9 represents according to the average transmission number of times simulation result schematic diagram based on 2 × 2MIMO system of the present invention.

In all above-mentioned accompanying drawings, identical label represents to have identical, similar or corresponding feature or function.

Embodiment

Embodiments of the present invention are specifically described below in conjunction with accompanying drawing.

Embodiments of the present invention realize based on mimo system, and be description aspect, for 2 × 2 antenna systems, but the present invention is not limited thereto.It will be understood by those of skill in the art that mimo system has a lot of selectable antenna to configure, and can the present invention be applied to.Above-mentioned setting is only exemplary illustration.

In mimo systems, if at receiving terminal generation decoding error, generally caused by three reasons: the cochannel that the deep fade (3) of noise (2) time varying channel that (1) is a large amount of is serious disturbs.When applying HARQ technology and improving the reliability of data packet transmission, the selection of retransmission scheme need be adaptively selected according to different error reasons.When the transmitting terminal at mimo system receives NAK message, namely transmitting terminal knows that the packet be sent out is by noise and channel deep fade, or noise and cochannel interference, or more the heavy damage and produce decoding error together of three reasons.

For reducing implementation complexity, in the present invention, first time retransmits selection HARQ scheme based on STBC, to resist channel deep fade, namely carries out Space Time Coding to the data of initial transmission.

If initial transmission and first time retransmit empty time decoding after there is mistake, illustrates that mimo channel is disturbed by serious cochannel, now the HARQ scheme of a re-transmission selection closed-loop MIMO system.

The HARQ scheme of closed-loop MIMO system is still selected in ensuing re-transmission, until receiving terminal is decoded correctly or reached the maximum retransmission of default.

That is, the present invention is on the basis of reason analyzing receiving terminal generation decoding error in mimo system, the adaptively selected retransmission scheme of number of retransmissions of giving chapter and verse, first time retransmits the HARQ retransmission technique selected based on STBC, wherein retransmission data packet may keeps identical data, and allows the change of data symbol, Data Conjugate change and the change of antenna assignment.This twice re-transmission forms a STBC code word (based on packet).The full diversity gains produced due to STBC and antenna array gain can resist channel fading, and each re-transmission can improve the probability that packet correctly receives.Second time and the ensuing HARQ scheme retransmitting employing closed-loop MIMO system, each re-transmission, receiving terminal estimates channel status according to Received signal strength, and calculate a pre-coding matrix according to channel condition information, and by this precoding matrix index feedback to transmitting terminal, transmitting terminal selects a pre-coding matrix according to the pre-coding matrix index received, and retransmits to receiving terminal again, make re-transmission obtain diversity gain to these data retransmitted after carrying out precoding; Meanwhile, receiving terminal is according to given re-transmission merging type, and as Chase Merge Scenarios and incremental redundancy Merge Scenarios etc., the data that merging repeatedly retransmits are to obtain higher merging gain to improve decoding probability.

Further, the present invention also proposes a combined optimization algorithm, channel condition information when channel condition information when receiving terminal is transmitted by the former secondary data bag of associating and current data packet transmission calculates the weights of global optimization and the pre-coding matrix of global optimization, re-transmission is made to obtain larger diversity gain, to resist the interference with minizone in community.Concrete, based on maximum S/N R criterion, the pre-coding matrix of calculation optimization.Be about to the packet that received and retransmit next time the packet of reception to combine carry out symbol level merging, export signal to noise ratio SNR criterion after maximization symbol level merges under, calculate pre-coding matrix.

The present invention merges the symbol level of receiving terminal and is also optimized further, by the front packet received several times respectively cancellation decode after correct packet and carry out symbol level merging with this packet received, carry out combined decoding after symbol level merging.Equally, the optimization that symbol level merges also can be applicable in combined optimization algorithm, be about to the packet that received respectively cancellation decoded after correct packet and retransmitted next time the packet of reception to combine and carried out symbol level merging, maximize export the criterion of signal to noise ratio SNR after symbol level merges under calculate pre-coding matrix.

In addition, also can incorporating selectively retransmit in the present invention, namely receiving terminal is according to decoding cases, decode error information is fed back to transmitting terminal, and transmitting terminal is according to decode error information, and the packet of selective decompression mistake is as retransmission data packet may, and send together with new data packets, to increase throughput.

Composition graphs 2, illustrates the course of work of adaptive HARQ.In the present embodiment, setting maximum retransmission is 2.In addition in order to reduce the expense of precoding matrix feedback, the present embodiment adopts the form feeding back precoding matrix based on code book (codebook), namely receiving-transmitting sides pre-defines the code character of finite length, receiving terminal is according to the pre-coding matrix calculated, then find the index value representing this pre-coding matrix in the codebook and feed back to transmitting terminal, transmitting terminal, according to the pre-coding matrix received, finds corresponding pre-coding matrix in the codebook, carries out precoding to eliminate cochannel interference.During system initialization, receiving terminal, transmitting terminal will receive number of times respectively, and number of retransmissions is initialized as 0, arrange a set point and maximum retransmission is 2, and configure code book.

In step S201 place, transmitting terminal sends initial data packets (S ₁, S ₂).

In step S211 place, receiving terminal receives packet, and Received signal strength can be expressed as:

$\left(\begin{array}{c}{r}_1\\ r_2\end{array}\right)=\left(\begin{array}{cc}{h}_{11}& h_{12}\\ h_{21}& h_{22}\end{array}\right)\left(\begin{array}{c}{S}_1\\ S_2\end{array}\right)+\left(\begin{array}{c}{n}_1\\ n_2\end{array}\right)---\left(3\right)$

Wherein h _{i, j}, i, j=1,2, be the channel coefficients between reception antenna i and transmitting antenna j.Receiving terminal judges that receiving number of times is 0, and directly decode the data received, hypothesis decoding mistake, adds 1 by reception number of times, stores the data received, and feeds back a NAK message.

In step S202 place, transmitting terminal receives NAK message, and number of retransmissions adds 1, and judges it is retransmit first time, then select to retransmit with the HARQ technology based on STBC, retransmission data packet may is (-S ₂ ^*, S ₁ ^*).

In step S212 place, the signal indication that receiving terminal receives is as follows:

$\left(\begin{array}{c}{r}_1\\ r_2\end{array}\right)=\left(\begin{array}{cc}{h}_{11}& h_{12}\\ h_{21}& h_{22}\end{array}\right)\left(\begin{array}{c}-S_2^{*}\\ S_1^{*}\end{array}\right)+\left(\begin{array}{c}{n}_1\\ n_2\end{array}\right)---\left(4\right)$

Judge that receiving number of times is 1, then merge formula (3), (4), obtain:

$\left(\begin{array}{c}{r}_1\\ r_2\\ r_1^{*}\\ r_2^{*}\end{array}\right)=\left(\begin{array}{cc}{h}_{11}& h_{12}\\ h_{21}& h_{22}\\ h_{11}^{*}& {-h}_{12}^{*}\\ h_{21}^{*}& -h_{22}^{*}\end{array}\right)\left(\begin{array}{c}{S}_1\\ S_2\end{array}\right)+\left(\begin{array}{c}{n}_1\\ n_2\\ n_1^{*}\\ n_2^{*}\end{array}\right)---\left(5\right)$

On formula (5) basis, carry out joint-detection to received signal: symbol level merges, and decodes.Hypothesis decoding mistake, then judges that receiving number of times is 1, is less than maximum retransmission 2, then receives number of times and add 1, store the data received, and calculate pre-coding matrix: suppose that the Received signal strength after retransmit i.e. second time retransmits next time can be expressed as follows:

$\left(\begin{array}{c}\widetilde{r_1}\\ \widetilde{r_2}\end{array}\right)=\left(\begin{array}{cc}{h}_{11}^{\left(l\right)}& h_{12}^{\left(l\right)}\\ h_{21}^{\left(l\right)}& h_{22}^{\left(l\right)}\end{array}\right)W\left(\begin{array}{c}{S}_1\\ S_2\end{array}\right)+\left(\begin{array}{c}{\tilde{n}}_1\\ {\tilde{n}}_2\end{array}\right)$

$=\left(\begin{array}{cc}{h}_{11}^{\left(l\right)}{W}_{11}^{\left(1\right)}+h_{12}^{\left(l\right)}{W}_{21}^{\left(l\right)}& h_{11}^{\left(l\right)}{W}_{12}^{\left(1\right)}+h_{12}^{\left(l\right)}{W}_{22}^{\left(l\right)}\\ h_{21}^{\left(l\right)}{W}_{11}^{\left(1\right)}+h_{22}^{\left(l\right)}{W}_{11}^{\left(l\right)}& h_{21}^{\left(l\right)}{W}_{12}^{\left(1\right)}+h_{22}^{\left(l\right)}{W}_{22}^{\left(l\right)}\end{array}\right)\left(\begin{array}{c}{S}_1\\ S_2\end{array}\right)+\left(\begin{array}{c}{\tilde{n}}_1\\ {\tilde{n}}_2\end{array}\right)---\left(6\right)$

Wherein, 1 represents the number of transmissions, and now 1=3, W represent pre-coding matrix, i, j=1,2, be precoding weight coefficient when adopting the HARQ scheme of closed-loop MIMO first time.

Merge formula (5) and (6) can obtain:

$\left(\begin{array}{c}{r}_1\\ r_2\\ r_1^{*}\\ r_2^{*}\\ {\tilde{r}}_1\\ {\tilde{r}}_2\end{array}\right)=\left(\begin{array}{cc}{h}_{11}& h_{12}\\ h_{21}& h_{22}\\ h_{11}^{*}& -h_{12}^{*}\\ h_{21}^{*}& -h_{22}^{*}\\ h_{11}^{\left(l\right)}{W}_{11}^{\left(1\right)}+h_{12}^{\left(l\right)}{W}_{21}^{\left(1\right)}& h_{11}^{\left(l\right)}{W}_{12}^{\left(1\right)}+h_{12}^{\left(l\right)}{W}_{22}^{\left(1\right)}\\ h_{21}^{\left(l\right)}{W}_{11}^{\left(1\right)}+h_{22}^{\left(l\right)}{W}_{211}^{\left(1\right)}& h_{21}^{\left(l\right)}{W}_{12}^{\left(1\right)}+h_{22}^{\left(l\right)}{W}_{22}^{\left(1\right)}\end{array}\right)\left(\begin{array}{c}{S}_1\\ S_2\end{array}\right)+\left(\begin{array}{c}{n}_1\\ n_2\\ n_1^{*}\\ n_2^{*}\\ {\tilde{n}}_1\\ {\tilde{n}}_2\end{array}\right)---\left(7\right)$

Its simplified expression is

$r=\tilde{H}s+\tilde{n}---\left(8\right)$

the aggregate channel repeatedly transmitted, be the noise after repeatedly transmitting merging, s is the multichannel data bag of transmission, and r represents the Received signal strength after repeatedly transmission.SNR after symbol level detection merges can calculate according to formula (7), is expressed as the function of W, namely

${\mathrm{\γ}}_i=\frac{{\left|g_i{\tilde{h}}_i\right|}^2{E}_s}{{\mathrm{\Σ}}_{j=1,j\≠i}^2{\left|g_i{\tilde{h}}_j\right|}^2{E}_s+{\left|\right|g_i\left|\right|}^2{N}_0}---\left(9\right)$

Wherein, g _ibe the row vector of least mean-square error MMSE weights, be expressed as

$G={[{\tilde{H}}^H\tilde{H}+\frac{N_0}{E_s}I]}^{-1}{\tilde{H}}^H$

$={[g_1,g_2]}^T---\left(10\right)$

[] ^trepresent the transposition of vector, [] ^-1represent finding the inverse matrix, () ^hrepresent the conjugate transpose of vector, I representation unit matrix.And be i-th column vector.Based on maximum S/N R criterion, calculate the pre-coding matrix of optimization, namely

$W^{\left(1\right)}=\underset{W^{\left(1\right)}}{\arg \max }\mathrm{\γ}(h_1,h_2,h_1^{\left(3\right)},h_2^{\left(3\right)};W^{\left(1\right)})---\left(11\right)$

Wherein, argmax represents the value of the W (1) asked when making γ maximum, and γ represents that receiving terminal merges the SNR exported, h ₁=[h ₁₁, h ₁₂], h ₂=[h ₂₁, h ₂₂], receiving terminal, according to the pre-coding matrix calculated, finds corresponding pre-coding matrix index and this pre-coding matrix index is fed back to transmitting terminal together with a NAK message in code table.

In step S203 place, transmitting terminal receives the pre-coding matrix index of NAK message and feedback, number of retransmissions adds 1, judgement is that second time retransmits, then select corresponding pre-coding matrix in the codebook according to the pre-coding matrix index of feedback message, after pre-coding matrix is carried out to retransmission data packet may, send to receiving terminal.

In step S213 place, the signal indication that receiving terminal receives is as shown in formula (7).On formula (7) basis, carry out symbol level merging to received signal, and decode.Hypothesis decoding is correct, set to 0 by reception number of times, and feeding back ACK message is to transmitting terminal.

In step S204 place, transmitting terminal receives ACK message, is set to 0 by number of retransmissions, and sends new data packets.

Without loss of generality, it is the course of work of the adaptive HARQ of L that Fig. 3 provides according to the maximum retransmission of an embodiment of the invention, L > 2.Further, in the embodiment that Fig. 3 represents, merge to optimize and carry out selective retransmission based on decode error information to the symbol level of receiving terminal and be also described in detail.Equally, in order to reduce the expense of precoding matrix feedback, the present embodiment adopts the form feeding back precoding matrix based on code book (codebook).During system initialization, receiving terminal, transmitting terminal will receive number of times respectively, and number of retransmissions is initialized as 0, arrange a set point and maximum retransmission is L, and configure code book.

In step S301 place, transmitting terminal sends initial data packets (S ₁, S ₂).

In step S311 place, receiving terminal receives packet, and Received signal strength such as formula (3) represents.

Receiving terminal judges that receiving number of times is 0, to the data direct-detection decoding received, supposes S ₁decoding error, S ₂decoding is correct, and reception number of times is added 1, stores the data received, and feeds back a NAK message and packet error information.

In step S302 place, transmitting terminal receives NAK message, and number of retransmissions adds 1, and judges it is retransmit first time, according to the packet error Information Selection received only by S ₁retransmit, and by (-S ₃ ^*, S ₁ ^*) as the packet transmitted.As shown in table 3.

Table 3

In step S312 place, the signal indication that receiving terminal receives is as follows:

$\left(\begin{array}{c}{r}_1\\ r_2\end{array}\right)=\left(\begin{array}{cc}{h}_{11}& h_{12}\\ h_{21}& h_{22}\end{array}\right)\left(\begin{array}{c}-S_3^{*}\\ S_1^{*}\end{array}\right)+\left(\begin{array}{c}{n}_1\\ n_2\end{array}\right)---\left(12\right)$

Judge that receiving number of times is 1, then the data that first time receives and this receives are carried out symbol level merging, according to first time packet error information, by the packet S that the signal cancellation that first time receives is decoded correct ₂, by the h in formula (3) ₁₂, h ₂₂set to 0.Namely formula (3) is revised as:

$\left(\begin{array}{c}{r}_1\\ r_2\end{array}\right)=\left(\begin{array}{cc}{h}_{11}& 0\\ h_{21}& 0\end{array}\right)\left(\begin{array}{c}{S}_1\\ S_2\end{array}\right)+\left(\begin{array}{c}{n}_1\\ n_2\end{array}\right)---\left(13\right)$

Merge formula (12), (13), obtain formula (14)

$\left(\begin{array}{c}{r}_1\\ r_2\\ r_1^{*}\\ r_2^{*}\end{array}\right)=\left(\begin{array}{cc}{h}_{11}& 0\\ h_{21}& 0\\ h_{11}^{*}& {-h}_{12}^{*}\\ h_{21}^{*}& -h_{22}^{*}\end{array}\right)\left(\begin{array}{c}{S}_1\\ S_3\end{array}\right)+\left(\begin{array}{c}{n}_1\\ n_2\\ n_1^{*}\\ n_2^{*}\end{array}\right)---\left(14\right)$

Carry out joint-detection to received signal, symbol level merges, and decodes.Suppose S ₁decoding error, then judges that receiving number of times is 1, is less than maximum retransmission L, then receives number of times and add 1, store the data received, and calculate pre-coding matrix.The calculating of pre-coding matrix as described in step S212, unlike, formula (7) is revised as following formula (15):

$\left(\begin{array}{c}{r}_1\\ r_2\\ r_1^{*}\\ r_2^{*}\\ {\tilde{r}}_1\\ {\tilde{r}}_2\end{array}\right)=\left(\begin{array}{cc}{h}_{11}& 0\\ h_{21}& 0\\ h_{11}^{*}& 0\\ h_{21}^{*}& 0\\ h_{11}^{\left(l\right)}{W}_{11}^{\left(1\right)}+h_{12}^{\left(l\right)}{W}_{21}^{\left(1\right)}& h_{11}^{\left(l\right)}{W}_{12}^{\left(1\right)}+h_{12}^{\left(l\right)}{W}_{22}^{\left(1\right)}\\ h_{21}^{\left(l\right)}{W}_{11}^{\left(1\right)}+h_{22}^{\left(l\right)}{W}_{211}^{\left(1\right)}& h_{21}^{\left(l\right)}{W}_{12}^{\left(1\right)}+h_{22}^{\left(l\right)}{W}_{22}^{\left(1\right)}\end{array}\right)\left(\begin{array}{c}{S}_1\\ S_2\end{array}\right)+\left(\begin{array}{c}{n}_1\\ n_2\\ n_1^{*}\\ n_2^{*}\\ {\tilde{n}}_1\\ {\tilde{n}}_2\end{array}\right)---\left(15\right)$

Be about to first time, the packet that second time receives respectively cancellation is decoded after correct packet and is carried out symbol level merging.The pre-coding matrix maximized under SNR is asked to be according to formula (15)

$W^{\left(1\right)}=\underset{W^{\left(1\right)}}{\arg \max }\mathrm{\γ}(h_1,h_2,h_1^{\left(3\right)},h_2^{\left(3\right)};W^{\left(1\right)})---\left(16\right)$

Wherein, argmax represents the value of the W (1) asked when making γ maximum, and γ represents that receiving terminal merges the SNR exported, now h ₁=[h ₁₁, h ₁₂], h ₂=[h ₂₁, h ₂₂], middle h ₂₁be 0, h ₂₂be 0.Receiving terminal, according to the pre-coding matrix calculated, finds corresponding pre-coding matrix index and this pre-coding matrix index, NAK message is fed back to transmitting terminal together with decoded packet data error message in code table.

In step S303 place, transmitting terminal receives the pre-coding matrix index of NAK message and feedback, and number of retransmissions adds 1, and judgement is that second time re-transmission is less than maximum retransmission L, according to the packet error Information Selection received only by S ₁retransmit, and by (S ₁, S ₄) as the packet transmitted, wherein S ₄for new data packets.Then select corresponding pre-coding matrix in the codebook according to the pre-coding matrix index of feedback message, after pre-coding matrix is carried out to retransmission data packet may, send to receiving terminal.

In step S313 place, it is (L-1) that receiving terminal receives number of times, and the similar step S312 of processing procedure describes.Now formula (11) is revised as:

$W^{(L-2)}=\underset{W^{(L-2)}}{\arg \max }\mathrm{\γ}(h_1,h_2,h_1^{\left(3\right)},h_2^{\left(3\right)},...,h_1^{\left(L\right)},h_2^{\left(L\right)},W^{\left(1\right)},...,W^{(L-3)};W^{(L-2)})---\left(17\right)$

Wherein, argmax represents the W asked when making γ maximum ^(L-2)value, and γ represent receiving terminal merge export SNR, L represents maximum transmission times, h _i=[h _{i, 1}, h _{i, 2}], i=1,2.Also 0 is corresponded at each weights retransmitting the correct data of decoding corresponding.

Step S304 place, the similar step S303 of transmitting terminal processing procedure describes.

In step S314 place, receiving terminal receives packet and decodes after optimization symbol level merging treatment, similar step S312 respective process, and hypothesis decoding mistake judges that receiving number of times is L, reaches maximum retransmission.Then reception number of times set to 0 and feed back a NAK message.

In step S305 place, transmitting terminal receives a NAK message, judges that number of retransmissions is L, has reached the maximum retransmission of setting, and transmitting terminal sends new data packets.

Fig. 4 gives the indicative flowchart of the HARQ repeating method according to an embodiment of the invention.

In step S401 place, transmitting terminal arranges maximum retransmission.And number of retransmissions initialization is set to 0, code book is set.

In step S402 place, transmitting terminal transmission packet.In step S403 place, receiving feedback information.

In step S404 place, judge whether to receive the maximum retransmission that ACK message or number of retransmissions reach setting, as long as meet both arbitrary conditions, enter step S405, number of retransmissions is set to 0, in step S406 place, selects new data packets and return step S402 place transmission new data packets; If receive NAK message and number of retransmissions is less than the maximum retransmission of setting, then enter step S407, select retransmission data packet may.According to one embodiment of present invention, retransmission data packet may can be initialization packet; According to another embodiment of the invention, comprise a packet decode error information in feedback message, according to decoded packet data error message, the packet of selective decompression mistake is as retransmission data packet may and as the packet that this retransmits together with new data packets.

In step S408 place, number of retransmissions is added 1.In step S409 place, judge whether number of retransmissions is 1, if so, then enters step S410, by the retransmission data packet may of selection to carry out retransmitting based on the HARQ mode of STBC and to return step S402 place transmission new data packets; If judge that number of retransmissions is not 1, then enter step S411, corresponding pre-coding matrix is selected according to the pre-coding matrix index in feedback message, then in step S412 place, to retransmit the packet of selection based on the HARQ mode of closed-loop MIMO, the retransmission data packet may being about to select carries out precoding, then returns step S402 place transmission new data packets.

Fig. 5 gives the indicative flowchart receiving feedback method according to the HARQ of an embodiment of the invention.

In step S501 place, receiving terminal arranges maximum retransmission.And the initialization of reception number of times is set to 0, code book is set.

In step S502 place, receive packet.

In step S503 place, judge to receive whether number of times is 0, if so, then showing that this receives is receive first time, the data received directly is carried out detecting and decoding; If not, then showing that this receives is receive retransmission data packet may, then the packet received is carried out joint-detection.According to one embodiment of present invention, joint-detection is that the data that this received and the front data received several times are decoded after symbol level merges, and to obtain merging gain, reduces intra-cell interference and interval interference.According to another embodiment of the invention, adopt the symbol level merging treatment optimized, by the front packet received several times respectively cancellation decode after correct packet and merge at symbol level with this packet received.How decode correct packet the detailed process of carrying out symbol level merging and combined decoding of cancellation is described in detail above, repeats no more here.

Enter step S506 after decoding, judge that whether decoding is correct, if decoding is correct, enters step S508, reception number of times is set to 0 and sends ACK message, then return step S502 and receive packet.If decoding error, then enter step S509, judge further to receive number of times, if receive number of times to equal set point, namely reach maximum retransmission, then enter step S510, send NAK message and reception number of times is set to 0, then return step S502 and receive packet.

If receive number of times to equal 1, then enter step S511, reception number of times is added 1, store the data that this receives, enter step S512, send NAK message and packet error message.Return step S502 after performing step S512 and receive packet.

If receive number of times to be greater than the maximum retransmission that 1 is less than setting, then enter step S513, reception number of times is added 1, store the data that this receives, enter step S514, the data aggregate optimization that will receive is retransmitted to the data received and next time, under the criterion of maximum S/N R, calculates the pre-coding matrix retransmitted next time; According to another embodiment of the invention, calculate the symbol level merging treatment adopting optimization in pre-coding matrix process at combined optimization, be about to the packet that received respectively cancellation decode to retransmit with next time after correct packet the packet of reception merged at symbol level.How combined optimization calculates pre-coding matrix and adopts the processes such as the symbol level merging treatment of optimization to be described in detail above, repeats no more here.Then enter step S515, send NAK message, pre-coding matrix index and packet error information, return step S502 afterwards and receive packet.

According to another embodiment of the invention, in the process of step S512 and step S515, packet error message also can not send.

Fig. 6 provides the structural schematic block diagram of the retransmission arrangement according to an embodiment of the invention.

In embodiments of the present invention, retransmission arrangement 600, for transmission/retransmission data packet may, comprises receiving element 601, judging unit 602, processing unit 603 and transmitting element 604.

Particularly, receiving element 601 can be configured to obtain feedback message, feedback message can be { ACK message }, { NAK message }, { NAK message, decoded packet data error message }, { NAK message, pre-coding matrix index }, or { NAK message, pre-coding matrix index, decoded packet data error message }.ACK message or NAK message are input to judging unit 602.Decoded packet data error message and pre-coding matrix index are input to processing unit 603, and the former is for selecting retransmission data packet may, and the latter is used for carrying out precoding to retransmission data packet may in the HARQ mode of closed-loop MIMO.

Judging unit judges that feedback message is ACK message, or NAK message, and judges number of retransmissions, and judged result is input to processing unit 603.

Processing unit 603 is configured to according to the adaptively selected retransmission scheme of judged result, if ACK message, processing unit 603 is selected new data packets and be input to transmitting element 604 to send; If NAK message, then further according to the judged result of number of retransmissions, if number of retransmissions has reached the maximum retransmission of setting, processing unit 603 has been selected new data packets and has been input to transmitting element 604 to send; If NAK message and number of retransmissions are 1 be less than maximum retransmission, the adaptively selected HARQ mode process retransmission data packet may based on STBC of processing unit 603 is also input to transmitting element 604 and carries out data packet retransmission; If NAK message and number of retransmissions is greater than 1 is less than maximum retransmission, the adaptively selected HARQ mode process retransmission data packet may based on closed-loop MIMO of processing unit 603 is also input to transmitting element 604 and carries out data packet retransmission.The detailed process of the HARQ mode process retransmission data packet may based on STBC and the HARQ mode process retransmission data packet may based on closed-loop MIMO is described in detail above, repeats no more here.

Transmitting element 604 is configured to send packet or retransmission data packet may.

Fig. 7 provides the structural schematic block diagram of the reception feedback device according to an embodiment of the invention.

In embodiments of the present invention, receive feedback device 700 and carry out message feedback for receiving packet and detecting according to packet, comprise receiving element 701, judging unit 702, detecting unit 703 and feedback unit 704.

Particularly, receiving element 701 is configured to receive packet.The packet received is input to detecting unit 703.

Judging unit 702 is configured to judge receive number of times and judge packet testing result.First judge to receive number of times, the judged result receiving number of times is input to detecting unit 703.

If detecting unit 703 is configured to carry out packet detection according to receiving number of times, if receiving number of times is 0, detecting unit 703 performs packet direct-detection, if receive number of times to be greater than 0, then performs packet joint-detection.According to one embodiment of present invention, joint-detection is that the data that this received and the front data received several times are decoded after symbol level merges, and to obtain merging gain, reduces intra-cell interference and interval interference.According to another embodiment of the invention, adopt the symbol level merging treatment optimized, by the front packet received several times respectively cancellation decode after correct packet and merge at symbol level with this packet received.How decode correct packet the detailed process of carrying out symbol level merging and combined decoding of cancellation is described in detail above, repeats no more here.

The result that packet detects is input to judging unit again, and packet testing result judges and receive number of times to judge to be input to feedback unit 704 by judging unit.

Feedback unit 704 is configured to generate feedback message according to according to reception number of times and packet testing result and send feedback message.Concrete, feedback message can be { ACK message }, { NAK message }, { NAK message, decoded packet data error message }, { NAK message, pre-coding matrix index }, or { NAK message, pre-coding matrix index, decoded packet data error message }.If judging unit 702 to input decoded packet data correct, then feedback unit 704 production ACK message send this message, reception number of times sets to 0 by judging unit 702; If input decoded packet data error message, then process according to reception number of times judged result further, if receive number of times to reach set point, i.e. maximum retransmission, feedback unit 704 generates NAK message and feeds back this NAK message again; Reception number of times sets to 0 by judging unit 702, if judge that receiving number of times equals 1, reception number of times is added 1 by judging unit 702, and detecting unit 703 stores this data received, and feedback unit 704 generates NAK message and packet error message and feeds back NAK message and packet error message.If receive number of times to be greater than the maximum retransmission that 1 is less than setting, then reception number of times is added 1 by judging unit 702, detecting unit 703 stores this data received, and feedback unit 704 calculates a pre-coding matrix and generation includes the feedback message of this pre-coding matrix index, NAK message and packet error message and feeds back.The computational process of pre-coding matrix is described in detail above, repeats no more here.

According to another embodiment of the invention, also packet error message can not be generated at feedback unit 704.

Figure (8), figure (9) provide respectively according to the throughput simulation result based on 2 × 2MIMO system of the present invention and average the number of transmissions simulation result, and compare based on the throughput of system of the HARQ of STBC, average transmission number of times with adopting.Simulation parameter is as shown in table 4, table 4

According to figure (8), figure (9), can find out, compared to the HARQ scheme based on STBC, adopt adaptive HARQ of the present invention, throughput of system increases, and average transmission number of times reduces, and therefore system delay can reduce.In addition, compared to the HARQ system based on closed-loop MIMO, because first time adopts the HARQ based on STBC to retransmit, complexity reduces relatively.Therefore, the present invention has a compromise preferably between performance and complexity.Therefore, the present invention can obtain between performance and complexity and compromise preferably.

The present invention can realize with hardware, software, firmware and their combination.One skilled in the art would recognize that and also can embody the present invention in computer program set on the signal bearing medium for any suitable data treatment system.This signal bearing medium can be transmission medium or the recordable media for machine sensible information, comprises magnetizing mediums, light medium or other suitable media.The example of recordable media comprises: the disk in hard disk drive or floppy disk, the CD for CD-ROM drive, tape, and those skilled in the art's other media thinkable.One skilled in the art would recognize that any communication equipment with suitable programmed device all can perform the step as the inventive method embodied in program product.

Should be appreciated that from foregoing description, without departing from the spirit of the invention, can each execution mode of the present invention be modified and be changed.Description in this specification is only used for illustrative, and should not be considered to restrictive.Scope of the present invention is only by the restriction of claims.

Claims (49)

1. an adaptive HARQ method, the method comprises:

Transmitting terminal sends packet;

Receiving terminal receives described packet;

Receiving terminal judges to receive number of times, according to reception number of times determination data packet inspection method; According to packet testing result with receive number of times and feed back different message to transmitting terminal, the message that wherein said feedback is different comprise for specific testing result and/or receive in the information of the instruction pre-coding matrix of number of times feedback except affirmative acknowledgement (ACK) and negative response (NACK) and decoded packet data error message at least one;

Transmitting terminal receives feedback message, determines retransmission scheme and retransmit content according to feedback message and number of retransmissions.

2. method according to claim 1, wherein,

Described receiving terminal judges to receive number of times, comprises: if receiving number of times is 0, directly decode to reception packet according to reception number of times determination data packet inspection method; Otherwise the packet of this reception and the front packet received several times are combined after symbol level merges and decodes.

3. method according to claim 2, wherein said this packet received and the front packet received several times combined that carrying out decodes after symbol level merges refer to by the front packet received several times respectively cancellation decode after correct packet and carry out symbol level merging with this packet received, combine after symbol level merging and decode.

4. according to the method for Claims 2 or 3, wherein,

Feed back different message according to packet testing result and reception number of times to comprise to transmitting terminal:

If decoded packet data is correct, feed back an ACK message to transmitting terminal, receive number of times and be set to 0;

If decoded packet data mistake, judge

If receive number of times to reach a set point, feed back a NAK message to transmitting terminal, receive number of times and be set to 0;

If receive number of times be less than a set point, then store the packet of reception, reception number of times is added 1 and,

If receiving number of times is 1, receiving terminal sends a NAK message to transmitting terminal;

If receive number of times to be greater than 1, then calculate a pre-coding matrix and feed back this pre-coding matrix index and a NAK message to transmitting terminal.

5. method according to claim 4, wherein,

If feed back different message described according to packet testing result and reception number of times and comprise decoded packet data mistake further to transmitting terminal, receive number of times and be less than a set point, receiving terminal also sends a packet decode error information to transmitting terminal.

6. method according to claim 1, wherein,

Described transmitting terminal determines retransmission scheme according to feedback message and number of retransmissions and retransmits content to comprise:

If receive ACK message, send new data packets, number of retransmissions is set to 0;

If receive NAK message, number of retransmissions is added 1 and judges number of retransmissions:

If number of retransmissions is 1, using the packet that the packet of first time transmission transmits as this, and with the HARQ technology retransmission data packet may based on STBC to receiving terminal, the packet that described retransmission data packet may and first time send forms a STBC code word;

If number of retransmissions is not more than a default value, using the packet that the packet of first time transmission transmits as this, and select pre-coding matrix according to the pre-coding matrix index in feedback message, retransmit to receiving terminal after precoding is carried out to the packet of this transmission;

If number of retransmissions is greater than a default value, sends new data packets, number of retransmissions is set to 0.

7. method according to claim 6, wherein, further, the packet transmitted first time is need the packet retransmitted and the packet transmitted as this according to packet error Information Selection as this packet transmitted.

8. method according to claim 7, wherein, the packet of this transmission comprises new data packets further.

9. method according to claim 6, wherein, transmitting terminal is to refer to that based on the HARQ technology retransmission data packet may of STBC transmitting terminal sends the common strategic point of initial data packets.

10. method according to claim 6, wherein, transmitting terminal is to refer to that based on the HARQ technology retransmission data packet may of STBC transmitting terminal sends the orthogonal sequence corresponding to initial data packets.

11. methods according to claim 4, wherein, described calculating pre-coding matrix is based on maximum S/N R criterion, calculates the pre-coding matrix of optimization.

12. methods according to claim 11, wherein, retransmit the packet of reception to combine by the packet received and next time and carry out symbol level merging, under maximizing symbol level to merge the criterion of output signal-to-noise ratio SNR afterwards, calculate pre-coding matrix.

13. methods according to claim 12, wherein, the packet received and next time are retransmitted the packet of reception combined carry out symbol level merge refer to by the packet received respectively cancellation decoded after correct packet and carried out symbol level merging with retransmitting next time the packet of reception to combine.

14. methods according to any one of claim 4-5 and 11-13, wherein, described set point refers to the maximum retransmission of default.

15. methods according to any one of claim 6-10, wherein, described default value refers to the maximum retransmission of default.

The repeating method of 16. 1 kinds of adaptive HARQs, the method comprises:

Transmitting terminal sends packet;

Transmitting terminal receives feedback message, determine retransmission scheme according to feedback message and number of retransmissions and retransmit content, wherein said feedback message is for the specific testing result of receiving terminal and/or receive at least one that number of times comprises in the information of the instruction pre-coding matrix except affirmative acknowledgement (ACK) and negative response (NACK) and decoded packet data error message.

17. repeating methods according to claim 16, wherein,

Described transmitting terminal determines retransmission scheme according to feedback message and number of retransmissions and retransmits content to comprise:

If receive ACK message, send new data packets, number of retransmissions is set to 0;

If receive NAK message, number of retransmissions is added 1 and judges number of retransmissions:

If number of retransmissions is 1, using the packet that the packet of first time transmission transmits as this, and with the HARQ technology retransmission data packet may based on STBC to receiving terminal, the packet that described retransmission data packet may and first time send forms a STBC code word;

If number of retransmissions is not more than a default value, using the packet that the packet of first time transmission transmits as this, and select pre-coding matrix according to the pre-coding matrix index in feedback message, retransmit to receiving terminal after precoding is carried out to the packet of this transmission;

If number of retransmissions is greater than a default value, sends new data packets, number of retransmissions is set to 0.

18. repeating methods according to claim 17, wherein, further, the packet of first time transmission is referred to the packet retransmitted according to the packet error Information Selection needs in feedback message and the packet transmitted as this as the packet that this transmits.

19. repeating methods according to claim 18, wherein, the packet of this transmission comprises new data packets further.

20. repeating methods according to claim 17, wherein, transmitting terminal is to refer to that based on the HARQ technology retransmission data packet may of STBC transmitting terminal sends the common strategic point of the packet needing transmission.

21. repeating methods according to claim 17, wherein, transmitting terminal is to refer to that based on the HARQ technology retransmission data packet may of STBC transmitting terminal sends the orthogonal sequence corresponding to the packet needing transmission.

The reception feedback method of 22. 1 kinds of adaptive HARQs, the method comprises:

Receiving terminal receives packet;

Receiving terminal judges to receive number of times, according to reception number of times determination data packet inspection method;

According to packet testing result with receive number of times and feed back different message to transmitting terminal, the message that wherein said feedback is different comprises for specific testing result and/or receives number of times feedback packet containing at least one in the information of the instruction pre-coding matrix except affirmative acknowledgement (ACK) and negative response (NACK) and decoded packet data error message.

23. reception feedback methods according to claim 22, wherein,

Described receiving terminal judges to receive number of times, comprises: if receiving number of times is 0, directly decode to reception packet according to reception number of times determination data packet inspection method; Otherwise the packet of this reception and the front packet received several times are combined after symbol level merges and decodes.

24. reception feedback methods according to claim 23, wherein said this packet received and the front packet received several times combined that carrying out decodes after symbol level merges refer to by the front packet received several times respectively cancellation decode after correct packet and carry out symbol level merging with this packet received, combine after symbol level merging and decode.

25. reception feedback methods according to claim 23, wherein,

Feed back different message according to packet testing result and reception number of times to comprise to transmitting terminal:

If decoded packet data is correct, feed back an ACK message to transmitting terminal, receive number of times and be set to 0;

If decoded packet data mistake, judge

If receive number of times to reach a set point, feed back a NAK message to transmitting terminal, receive number of times and be set to 0;

If receive number of times be less than a set point, then store the packet of reception, reception number of times is added 1 and,

If receiving number of times is 1, receiving terminal sends a NAK message to transmitting terminal;

If receive number of times to be greater than 1, then calculate a pre-coding matrix and feed back this pre-coding matrix index and a NAK message to transmitting terminal.

26. reception feedback methods according to claim 25, wherein,

If feed back different message described according to packet testing result and reception number of times and comprise decoded packet data mistake further to transmitting terminal, receive number of times and be less than a set point, receiving terminal also sends a packet decode error information to transmitting terminal.

27. reception feedback methods according to claim 25, wherein, described calculating pre-coding matrix is based on maximum S/N R criterion, calculates the pre-coding matrix of optimization.

28. reception feedback methods according to claim 27, wherein, the packet received and next time are retransmitted the packet of reception to combine and carries out symbol level merging, under maximizing symbol level to merge the criterion of output signal-to-noise ratio SNR afterwards, calculate pre-coding matrix.

29. reception feedback methods according to claim 28, wherein, the packet received and next time are retransmitted the packet of reception combined carry out symbol level merge refer to by the packet received respectively cancellation decoded after correct packet and carried out symbol level merging with retransmitting next time the packet of reception to combine.

30. reception feedback methods according to any one of claim 25-29, wherein, described set point refers to the maximum retransmission of default.

The retransmission arrangement of 31. 1 kinds of adaptive HARQs, this device comprises:

Transmitting element, for sending packet;

Receiving element, for receiving feedback message, wherein said feedback message is for the specific testing result of receiving terminal and/or receive at least one that number of times comprises in the information of the instruction pre-coding matrix except affirmative acknowledgement (ACK) and negative response (NACK) and decoded packet data error message;

Judging unit, for judging feedback message and number of retransmissions;

Processing unit, for determining retransmission scheme according to feedback message and number of retransmissions and retransmitting content.

32. retransmission arrangement according to claim 31, wherein,

Describedly determine retransmission scheme according to feedback message and number of retransmissions and retransmit content to comprise:

If receive ACK message, send new data packets, number of retransmissions is set to 0;

If receive NAK message, number of retransmissions is added 1 and judges number of retransmissions:

If number of retransmissions is 1, using the packet that the packet of first time transmission transmits as this, and with the HARQ technology retransmission data packet may based on STBC to receiving terminal, the packet that described retransmission data packet may and first time send forms a STBC code word;

If number of retransmissions is not more than a default value, using the packet that the packet of first time transmission transmits as this, and select pre-coding matrix according to the pre-coding matrix index in feedback message, retransmit to receiving terminal after precoding is carried out to the packet of this transmission;

If number of retransmissions is greater than a default value, sends new data packets, number of retransmissions is set to 0.

33. retransmission arrangement according to claim 32, if wherein receive NAK message, the packet of first time transmission is referred to the packet retransmitted according to the packet error Information Selection needs in feedback message and the packet transmitted as this as the packet that this transmits.

34. retransmission arrangement according to claim 33, wherein, the packet of this transmission comprises new data packets further.

35. retransmission arrangement according to claim 32, wherein, to refer to the common strategic point sending the packet needing transmission based on the HARQ technology retransmission data packet may of STBC.

36. retransmission arrangement according to claim 32, wherein, to refer to the orthogonal sequence sent corresponding to the packet needing transmission based on the HARQ technology retransmission data packet may of STBC.

The reception feedback device of 37. 1 kinds of adaptive HARQs, this device comprises:

Receiving element, for receiving packet;

Judging unit, receives number of times and decoded packet data situation for judging;

Data packet detecting unit unit, for according to reception number of times determination data packet inspection method;

Feedback unit, for according to packet testing result with receive number of times and feed back different message, the message that wherein said feedback is different comprise for specific testing result and/or receive in the information of the instruction pre-coding matrix of number of times feedback except affirmative acknowledgement (ACK) and negative response (NACK) and decoded packet data error message at least one.

38. according to the reception feedback device of claim 37, wherein,

Describedly to comprise according to reception number of times determination data packet inspection method: if receiving number of times is 0, directly reception packet is decoded; Otherwise the packet of this reception and the front packet received several times are combined after symbol level merges and decodes.

39. according to reception feedback device according to claim 38, wherein said this packet received and the front packet received several times combined that carrying out decodes after symbol level merges refer to by the front packet received several times respectively cancellation decode after correct packet and carry out symbol level merging with this packet received, combine after symbol level merging and decode.

40. according to the reception feedback device of claim 38, wherein,

Feed back different message according to packet testing result and reception number of times to comprise:

If decoded packet data is correct, feed back an ACK message, receive number of times and be set to 0;

If decoded packet data mistake, judge

If receive number of times to reach a set point, feed back a NAK message, receive number of times and be set to 0;

If receive number of times be less than a set point, then store the packet of reception, reception number of times is added 1 and,

If receiving number of times is 1, receiving terminal sends a NAK message;

If receive number of times to be greater than 1, then calculate a pre-coding matrix and feed back this pre-coding matrix index and a NAK message.

41. reception feedback devices according to claim 40, wherein, feed back different message if described according to reception number of times and comprise decoded packet data mistake further, receive number of times and be less than a set point, also send a packet decode error information.

42. reception feedback devices according to claim 40, wherein, described calculating pre-coding matrix is based on maximum S/N R criterion, calculates the pre-coding matrix of optimization.

43. reception feedback devices according to claim 42, wherein, the packet received and next time are retransmitted the packet of reception to combine and carries out symbol level merging, under maximizing symbol level to merge the criterion of output signal-to-noise ratio SNR afterwards, calculate pre-coding matrix.

44. reception feedback devices according to claim 43, wherein, the packet received and next time are retransmitted the packet of reception combined carry out symbol level merge refer to by the packet received respectively cancellation decoded after correct packet and carried out symbol level merging with retransmitting next time the packet of reception to combine.

45. reception feedback devices according to claim 40, wherein, described set point refers to the maximum retransmission of default.

46. 1 kinds of network side equipment adopting adaptive HARQ, wherein, described network side equipment comprises the retransmission arrangement according to any one of claim 31-36.

47. 1 kinds of terminal equipments adopting adaptive HARQ, wherein, described terminal equipment comprises the retransmission arrangement according to any one of claim 31-36.

48. 1 kinds of network side equipment adopting adaptive HARQ, wherein, described network side equipment comprises the reception feedback device according to any one of claim 37-45.

49. 1 kinds of terminal equipments adopting adaptive HARQ, wherein, described terminal equipment comprises the reception feedback device according to any one of claim 37-45.