CN102474388B - Method and equipment for cooperative relaying used in wireless communication system - Google Patents

Abstract

The present application discloses a method and equipment for cooperative relaying used in wireless communications systems, wherein the method includes: receiving the data packets sent by the sending device via relay links; adaptively adjusting the format of the data packets to be sent to the receiving device via access links according to the power difference between the cooperative relay stations, in order to combine in the receiving device the data packets received from a sending device via a direct link and the data packets received from a cooperative relay station with low access link power via an access link, and to achieve spatial diversity between the cooperative relay stations; and sending the data packets to the receiving device via access links. The method and equipment of the present invention eliminate or reduce the power imbalance of the access links existing in the cooperative relay and maximize the diversity gain, thus improving wireless communications system performance.

Description

Method and apparatus for wireless communication system cooperating relay

Technical field

Present invention relates in general to wireless communication system, more specifically, the present invention relates to for the method and apparatus in wireless communication system cooperating relay.

Background technology

In multi-hop wireless communication system, cooperating relay is with distributed way, to obtain effective physical-layer techniques of diversity gain.The main thought of cooperating relay is via node to be considered as virtual-antenna, thereby helps lend some impetus to the right radio communication in single source-destination by implementing two key characters of wireless medium.Two key characters of this wireless medium are its broadcast nature and the ability that obtains space diversity or spatial reuse.By introduce cooperating relay technology between base station (BS) and/or trunk desk (RS), the performance of wireless communication system can further be improved.

Current, in multi-hop wireless communication system, common cooperating relay solution is in cooperating relay, to adopt distributed space time block coding (STBC) and distributed spatial reuse (SM).Data due to distributed STBC and SM transmission set form, receiving terminal only need to utilize channel information (this channel information transmits known reference signal by transmitting terminal and obtains) to carry out demodulation, and transmitting terminal is not need channel information, therefore they do not need feeding back channel state information (CSI), improved system performance and do not need extra signaling consumption effectively so just.

For the ease of understanding, Fig. 1 draws the illustrative example of the down link space diversity of above-mentioned cooperating relay, and wherein trunk desk RS1 and RS2 are by receiving packet (S via transmitting apparatus BS to the repeated link of RS1 and RS2 ₂, S ₁), and receiving equipment travelling carriage (MS) receives respectively packet (S by the access link via from RS1 and RS2 to MS ₂*, S ₁) and (S ₁*, S ₂), thereby realize distributed STBC.Therefore, array gain and cooperative reception diversity gain can be obtained, and the transmission quality of access link can be improved thus.

Yet, due to the difference of base station and trunk desk locus of living in, from base station or a plurality of trunk desk send to a plurality of signals of travelling carriage will the different path loss of experience, this will cause travelling carriage place to receive the unbalanced power (that is, unequal) of signal.Although can select suitable trunk desk to carry out relay transmission, but still the situation that is difficult to avoid such occurs.The unbalanced power of this reception signal will have influence on the acquisition of space diversity gain, and especially, when the unbalanced power of reception signal acquires a certain degree, possibly cannot implementation space diversity gain.

For example, in typical mobile environment, when path loss index is 4, the be separated by MS of two kilometers and BS and distance of distance is separated by between the MS and RS of a kilometer, and the difference of access link power path loss will reach 12dB.When carrying out collaborative process between BS and RS, space diversity gain will almost completely lose, and even performance may worsen further.

Fig. 2 is that emulation is worked as signal to noise ratio snr while being 4dB, and the diagram of unbalanced power on the impact of throughput performance, tells the amount of gulping down here and refer to the data rate (bps/Hz) transmitting under cell frequency.By this figure, can find out, when the unbalanced power on two access link (being also difference power) reaches 12dB, telling the amount of gulping down loss is approximately 83%, and this is almost identical with the multi-hop relay that does not have to cooperate.

In order to reduce the impact of unbalanced power, according to existing technical scheme, must select suitable via node, select to have to the node of MS same distance to realize collaborative process, and this will greatly limit the application scenarios of cooperating relay technology.

Therefore, need a kind of method and apparatus for wireless communication system cooperating relay, it can reduce or eliminate the unbalanced power on existing access link in cooperating relay, and realizes substantially diversity gain, thereby improves the performance of wireless communication system.

Summary of the invention

In view of there are the problems referred to above in prior art, the invention provides new solution, specific as follows:

According to an aspect of the present invention, provide a kind of method for wireless communication system cooperating relay, described method comprises: via repeated link, receive the packet sending from transmitting apparatus; According to the difference power between the trunk desk of cooperation, adjust adaptively and will via access link, send to the data packet format of receiving equipment, to the packet receiving from transmitting apparatus via direct link is merged with the packet receiving from the low access link power relay platform cooperating via access link at receiving equipment place, and realizes the space diversity between the trunk desk cooperating; And via access link, packet is sent to receiving equipment.

According to a further aspect in the invention, provide a kind of trunk desk for wireless communication system cooperating relay, described trunk desk comprises: receiving system, for receive the packet sending from transmitting apparatus via repeated link; Adjusting device, be used for according to the difference power between the trunk desk of cooperation, adjust adaptively and will via access link, send to the data packet format of receiving equipment, to the packet receiving from transmitting apparatus via direct link is merged with the packet receiving from the low access link power relay platform cooperating via access link at receiving equipment place, and realizes the space diversity between the trunk desk cooperating; Dispensing device, for sending to receiving equipment via access link by packet.

According to a further aspect in the invention, a kind of method for wireless communication system cooperating relay is provided, and described method comprises: via direct link, receive the packet sending from transmitting apparatus and via access link, receive the packet sending from the trunk desk of cooperation; The described packet receiving via direct link is merged with the packet receiving from the low access link power relay platform cooperating via access link, wherein the trunk desk of cooperation, according to mutual difference power, is adjusted adaptively and will be sent to the data packet format of receiving equipment via access link to realize the space diversity between the trunk desk of described merging and cooperation.

According to a further aspect in the invention, a kind of receiving equipment for wireless communication system cooperating relay is provided, described receiving equipment comprises: receiving system, for receiving the packet sending from transmitting apparatus via direct link and receiving the packet sending from the trunk desk of cooperation via access link; Merge device, for the described packet receiving via direct link is merged with the packet receiving from the low access link power relay platform cooperating via access link, wherein the trunk desk of cooperation, according to mutual difference power, is adjusted adaptively and will be sent to the data packet format of receiving equipment via access link to realize the space diversity between the trunk desk of described merging and cooperation.

According to another aspect of the invention, provide a kind of wireless communication system that uses cooperating relay, comprising: transmitting apparatus, for sending packet and send packet via repeated link to trunk desk to receiving equipment via direct link; The trunk desk of cooperation, for receiving via repeated link from the packet of transmitting apparatus and according to the difference power between the trunk desk of cooperation, adjust adaptively and will via access link, send to the data packet format of receiving equipment, to realize the space diversity at the packet merging at receiving equipment place and the trunk desk of cooperation; Receiving equipment, merges to obtain access link power identical between access link for the packet that the described packet receiving via direct link is received with low access link power relay platform from cooperation.

By implementing method provided by the present invention, trunk desk, receiving equipment and wireless communication system, can reduce or eliminate the unbalanced power on existing access link in cooperating relay, and realize substantially diversity gain, thereby improve the performance of wireless communication system.

Accompanying drawing explanation

By reading the following detailed description to non-limiting example with reference to accompanying drawing, it is more obvious that other features, objects and advantages of the present invention will become.In the accompanying drawings, identical with similar Reference numeral represents same or analogous device or method step, wherein:

Fig. 1 is the diagram of example that schematically shows the down link space diversity of cooperating relay;

Fig. 2 is the diagram of unbalanced power on the impact of throughput performance that schematically shows access link in cooperating relay;

Fig. 3 is the flow chart illustrating according to the method for wireless communication system cooperating relay of one embodiment of the present invention;

Fig. 4 is the block diagram illustrating according to the trunk desk for wireless communication system cooperating relay of one embodiment of the present invention;

Fig. 5 is the flow chart illustrating according to the method for wireless communication system cooperating relay of one embodiment of the present invention;

Fig. 6 is the block diagram illustrating according to the receiving equipment for wireless communication system cooperating relay of one embodiment of the present invention;

Fig. 7 is the detail flowchart schematically showing according to adaptive cooperation relay transmission in the down link of an embodiment of the invention;

Fig. 8 illustrates according to the present invention cooperate with nothing Packet Error Ratio (BLER) the Performance Ratio diagram of multi-hop relay and distributed STBC of the adaptive STBC collaboration method proposing;

Fig. 9 illustrates the adaptive space frequency chunks coding (SFBC) of another execution mode according to the present invention and the BLER Performance Ratio of distributed SFBC diagram;

Figure 10 is the simulation deployment figure that the adaptive space frequency chunks coding of another execution mode according to the present invention is shown; And

Figure 11 is the systematic function comparison diagram illustrating based on distributed SFBC method and adaptive cooperation trunking method proposed by the invention.

Embodiment

Below in conjunction with accompanying drawing, describe embodiments of the present invention in detail.

First with reference to figure 3, it illustrates according to the flow chart of the method for wireless communication system cooperating relay of one embodiment of the present invention.As shown in FIG., in step 301, via repeated link, receive the packet sending from transmitting apparatus.In step 302, according to the difference power between the trunk desk of cooperation, adjust adaptively and will via access link, send to the data packet format of receiving equipment, to the packet receiving from transmitting apparatus via direct link is merged with the packet receiving from the low access link power relay platform cooperating via access link at receiving equipment place, and realizes the space diversity between the trunk desk cooperating.And in step 303, via access link, packet is sent to described receiving equipment.

Fig. 4 is the block diagram illustrating according to the trunk desk for wireless communication system cooperating relay of one embodiment of the present invention.This trunk desk comprises receiving system 401, adjusting device 402 and dispensing device 403.Wherein, receiving system 401 is for receiving the packet sending from transmitting apparatus via repeated link.Adjusting device 402 for according to cooperation trunk desk between difference power, adjust adaptively and will via access link, send to the data packet format of receiving equipment, to the packet receiving from transmitting apparatus via direct link is merged with the packet receiving from the low access link power relay platform cooperating via access link at receiving equipment place, and realizes the space diversity between the trunk desk cooperating.Dispensing device 403 is for sending to described receiving equipment via access link by packet.

Fig. 5 is the flow chart illustrating according to the method for wireless communication system cooperating relay of one embodiment of the present invention.As shown in FIG., in step 501, via direct link, receive the packet sending from transmitting apparatus and via access link, receive the packet sending from the trunk desk of cooperation.Then,, in step 502, the described packet receiving via direct link is merged with the packet receiving from the low access link power relay platform cooperating via access link.Wherein, the trunk desk of cooperation is according to mutual difference power, adjusts adaptively and will send to the data packet format of receiving equipment via access link to realize the space diversity between the trunk desk of described merging and cooperation.

Fig. 6 is the block diagram illustrating according to the receiving equipment for wireless communication system cooperating relay of one embodiment of the present invention.As shown in FIG., this reception setting comprises receiving system 601 and merges device 602.Wherein, receiving system 601 is for receiving the packet sending from transmitting apparatus and receiving the packet sending from the trunk desk of cooperation via access link via direct link.Merge device 602 for the described packet receiving via direct link is merged with the packet receiving from the low access link power relay platform cooperating via access link.Wherein, the trunk desk of cooperation is according to mutual difference power, adjusts adaptively and will send to the data packet format of receiving equipment via access link to realize the space diversity between the trunk desk of described merging and cooperation.

According to above-mentioned a plurality of execution modes of the present invention, a kind of wireless communication system that uses cooperating relay is provided simultaneously, its functional block diagram is similar to shown in Fig. 1, therefore in this omission, this wireless communication system comprises: transmitting apparatus, and for sending packet and send packet via repeated link to trunk desk to receiving equipment via direct link.The trunk desk of cooperation, for receiving via repeated link from the packet of transmitting apparatus and according to the difference power between the trunk desk of cooperation, adjust adaptively and will via access link, send to the data packet format of receiving equipment, to realize the space diversity at the packet merging at receiving equipment place and the trunk desk of cooperation; And receiving equipment, for the packet that the described packet receiving via direct link is received with low access link power relay platform from cooperation, merge to obtain access link power identical between access link.

Fig. 7 is the detail flowchart schematically showing according to adaptive cooperation relay transmission in the down link of an embodiment of the invention;

In step 70, transmitting apparatus BS by repeated link to the trunk desk RS1 and the RS2 broadcast data packets (S that relate in collaborative process ₂, S ₁) and receiving equipment MS by direct link, receive and store and come from these packets of BS and these packets are not carried out to equilibrium and decoding is processed.

Then, in step 71 and 72, MS sends to RS1 and RS2 by the channel quality feedback information of the access link between itself and RS1 and RS2 respectively, this channel quality feedback information be according to from RS1 and RS2 previously received signal estimate.Here previously received signal refers to that MS is in previous time slot or the received reference signal of former frame, the channel information estimating by this reference signal can be used as the channel information of this time slot, because in the environment slowly changing in communication channel, adjacent time-slots can be thought constant.In above-mentioned steps, RS1 and RS2 carry out demodulation code to the data-signal receiving from BS simultaneously.

In step 73 and 74, RS1 and RS2 determine channel link quality condition separately (access link power level) separately according to the channel quality feedback information mentioned above respectively, and will determine adaptively as follows that it is by the data packet format transmitting to MS.That is, when there is difference power between RS1 and the access link of RS2, the RS of low access link power transmits the packet with the packet same format that is sent to MS with BS on direct link to MS in step 75 or 77, that is, and and packet (S ₂, S ₁).And another RS with high access link power transmits identical data content to MS in step 76 or 78, but this data packet format has been carried out to conversion (symbol and conjugater transformation) adaptively, that is, and packet (S ₁* ,-S ₂*).Thereby, from the data packet format of the transmission of RS1 and RS2, formation is met to the code word of space diversity coding rule.Preferably, the code word that meets STBC/SFBC coding rule.

Finally, at step 79 place, MS is receiving from access link from the packet of RS1 and RS2, by using the moving existing STBC/SFBC detection scheme of plan and control micromodification (, formula below adds h1 item in (7)), the packet receiving from the low RS of access link power and the packet previously receiving from BS through direct link are merged (preferably, high specific merges), the access power of the RS that power is lower is compensated thus, thereby can obtain substantially the diversity gain of the STBC/SFBC on repeated link, then improve the performance of wireless communication system.

Here needing is to be pointed out that the method proposing above the present invention is not limited to realize cooperating relay with two trunk desk RS, and it can be extended to the cooperation between BS and RS, or for the cooperation between a plurality of transmitting stations of up link or down link.For example, when carrying out cooperating relay on uplink direction, transmitting apparatus is MS, and receiving equipment is BS.In addition, by combination, be used for compensating the adaptive packet data format conversion technology of imbalance power, also make existing distributed STBC be enhanced.

The mode of expressing with formulism is further described to the execution mode of Fig. 7 below.Because Alamouti code is widely used STBC in wireless communication system, therefore between RS1 and RS2, carry out Alamouti code.

According to Fig. 7, when BS is sent to its packet after MS via direct link, received signal can represent as follows:

y ₁＝h ₁s ₁+n ₁(1)

y ₂＝h ₂s ₂+n ₂

S wherein ₁and s ₂the packet in continuous two time slots that send, h ₁and h ₂the respective channel state information from BS to MS, and n ₁and n ₂it is the additive white Gaussian noise of twice reception.Without loss of generality, equation (1) can be write as follows:

$\left(\begin{array}{c}{y}_1\\ y_2^{*}\end{array}\right)=\left(\begin{array}{cc}{h}_1& 0\\ 0& -h_2^{*}\end{array}\right)\left(\begin{array}{c}{s}_1\\ -s_2^{*}\end{array}\right)+\left(\begin{array}{c}{n}_1\\ n_2^{*}\end{array}\right)---\left(2\right)$

Here " * " represents conjugater transformation.When selecting RS1 and RS2 or BS and a RS work in coordination with transmission packet to obtain diversity gain, will use improved Alamouti code, meet the Alamouti code of the requirement of the data packet format sending via access link in the present invention.It is the coding based on direction in space that existing Alamouti encodes for two antenna STBC, and the 1st antenna sends (S ₁,-S ₂*) and the 2nd antenna sends (S ₂, S ₁*).Be different from the existing Alamouti coding method based on direction in space, after having considered the data format sending on direct link, improved Alamouti code proposed by the invention sends packet (S at the 1st antenna (being RS1 place) ₁, S ₂) and send (S at the 2nd antenna (being RS2 place) ₂*, S ₁*), based on time orientation, carry out coded data packet.Can find out, suppose that RS1 access link power is lower herein, thereby kept the data packet format identical with BS.Thereby MS can be write as follows from the received signal of access link:

$y_3=h_{11}{s}_1-h_{12}{s}_2^{*}+n_3$

$y_4=h_{11}{s}_2+h_{12}{s}_1^{*}+n_4$

H wherein ₁₁and h ₁₂be respectively the channel condition information from RS1 and RS2 to the access link of MS, suppose that RS1 and RS2 exist difference power between the two here, and RS1 be low to the access link power of MS, so its transmitted signal (s respectively in two continuous time slots ₁, s ₂).RS2 is high to the access link power of MS, so it sends respectively the signal through format conversion in two continuous time slots correspondingly, equation (3) can represent as follows:

$\left(\begin{array}{c}{y}_3\\ y_4^{*}\end{array}\right)=\left(\begin{array}{cc}{h}_{11}& h_{12}\\ h_{12}^{*}& -h_{11}^{*}\end{array}\right)\left(\begin{array}{c}{s}_1\\ -s_2^{*}\end{array}\right)+\left(\begin{array}{c}{n}_3\\ n_4^{*}\end{array}\right)---\left(4\right)$

Merge equation (2) and (4), can obtain

$\left(\begin{array}{c}{y}_1\\ y_2^{*}\\ y_3\\ y_4^{*}\end{array}\right)=\left(\begin{array}{cc}{h}_1& 0\\ 0& -h_2^{*}\\ h_{11}& h_{12}\\ h_{12}^{*}& -h_{11}^{*}\end{array}\right)\left(\begin{array}{c}{s}_1\\ -s_2^{*}\end{array}\right)+\left(\begin{array}{c}{n}_1\\ n_2^{*}\\ n_3\\ n_4^{*}\end{array}\right)---\left(5\right)$

Equation (5) can represent with following matrix form:

y＝hs+n(6)

From equation (5), can find out, channel state information matrix h reaches the diversity gain on three rank, and in the existing system shown in Fig. 1, distributed STBC only can obtain the diversity gain on two rank, the single order gain of this increase comes from equation (2) and merges with the data diversity of RS1 transmission, as high specific merges (MRC).Power by increasing the low access link of this diversity order improving gain is to eliminate unbalanced power.Be similar to and mention in STBC algorithm, suppose that between corresponding two continuous slots of channel on direct link be constant, i.e. h ₁=h ₂.Utilize existing STBC detection algorithm, equation (6) is multiplied by h ^*, the packet of transmission can recover as follows.

$\left(\begin{array}{c}{s}_1\\ -s_2^{*}\end{array}\right)=\frac{1}{{\left|h_1\right|}^2+{\left|h_{11}\right|}^2+{\left|h_{12}\right|}^2}{h}^{*}y---\left(7\right)$

Owing to using the signal sending on direct link, by high specific, merge the time diversity gain that (MRC) obtain and can there is for compensation the RS of low access power, thereby RS arrives equal power or the power of balance roughly, can obtain substantially the diversity gain between the STBC on repeated link thus.

Owing to considering MRC, have the RS of low access link power or BS send have with direct link on the packet of BS same-code form.Therefore, for example, when receiving equipment MS feeds back the channel quality information (signal to noise ratio snr) of two access link to RS, RS1 and RS2 self will determine STBC coded format adaptively, that is, the RS with low access link power in the continuous slot of access link, send ( _s1, s ₂), and another RS with high access link power sends in the continuous slot of access link

Use analysis above, can make emulation to the performance of adaptive cooperation relay transmission scheme, and for comparison purposes, to also carrying out emulation based on OFDM downlink system without cooperation multi-hop relay and distributed STBC, wherein, in this emulation, cooperation is carried out between BS and RS.Table 1 has provided the setting parameter of emulation.

Table 1

The simulation result of Fig. 8 illustrates in above-mentioned three kinds of situations, the comparison of Packet Error Ratio (BLER) performance.As desired, when path loss index is 4, difference power is approximately 13dB.Due to the direct link of the difference from BS to MS, distributed STBC is by the performance worsening in low SNR region, but in high SNR region, distributed STBC can obtain partial diversity gain, is therefore compared to when BLER=1 * 10 ^-3time multi-hop relay, its performance can be enhanced about 1dB.Due to by service time diversity gain compensate adaptively imbalance power, difference power is reduced.Therefore, be compared to when BLER=1 * 10 ^-3time the performance of distributed STBC, the performance of method proposed by the invention can improve about 3.8dB.

Adaptive cooperation scheme proposed by the invention can be extended in the cooperating relay wireless communication system based on SFBC.

Be similar to the description for the execution mode of STBC, the mode of expressing below by formulism is described method proposed by the invention use in the cooperating relay based on SFBC.Similarly, when BS sends after its packet on direct link, the packet that MS receives can be expressed as follows:

y ₁(k)＝h ₁(k)s ₁(k)+n ₁(k)(8)

y ₂(k+1)＝h ₂(k+1)s ₂(k+1)+n ₂(k+1)

Wherein k represents the subcarrier in ofdm system, s ₁and s (k) ₂(k+1) be the packet sending in two continuous subcarrier k and k+1, h ₁and h (k) ₂(k+1) be the respective channel state information of the direct link from BS to MS, and n ₁and n (k) ₂(k+1) be the additive white Gaussian noise of twice reception.Without loss of generality, equation (8) can be write as follows:

$\left(\begin{array}{c}{y}_1\left(k\right)\\ y_2^{*}(k+1)\end{array}\right)=\left(\begin{array}{cc}{h}_1\left(k\right)& 0\\ 0& -h_2^{*}(k+1)\end{array}\right)\left(\begin{array}{c}{s}_1\left(k\right)\\ -s_2^{*}(k+1)\end{array}\right)+\left(\begin{array}{c}{n}_1\left(k\right)\\ n_2^{*}(k+1)\end{array}\right)---\left(9\right)$

Wherein " * " represents conjugater transformation.When two RS or BS and a RS selected to work in coordination with transmission packet, thereby while obtaining diversity gain.Be similar to the description in distributed STBC above, also can use improved Alamouti code, the method that proposed is based on frequency direction but not direction in space carrys out coded data packet, that is, MS received signal from two subcarriers of the access link of cooperation is

$y_3\left(k\right)=h_{11}\left(k\right)s_1\left(k\right)-h_{12}\left(k\right)s_2^{*}(k+1)+n_3\left(k\right)$

$y_4(k+1)=h_{11}(k+1)s_2(k+1)+h_{12}(k+1)s_1^{*}\left(k\right)+n_4(k+1)$

H wherein ₁₁and h (k) ₁₂(k) be respectively that the upper trunk desk from two cooperations of access link sub-carriers k of cooperation is to the channel condition information of MS.The channel condition information of supposing continuous two subcarriers is constant, that is, and and h ₁(k)=h ₂(k+1), h ₁₁(k)=h ₁₁(k+1), h ₁₂(k)=h ₁₂(k+1), equation (10) can represent as follows:

$\left(\begin{array}{c}{y}_3\left(k\right)\\ y_4^{*}(k+1)\end{array}\right)=\left(\begin{array}{cc}{h}_{11}\left(k\right)& h_{12}\left(k\right)\\ h_{12}^{*}\left(k\right)& -h_{11}^{*}\left(k\right)\end{array}\right)\left(\begin{array}{c}{s}_1\left(k\right)\\ -s_2^{*}(k+1)\end{array}\right)+\left(\begin{array}{c}{n}_3\left(k\right)\\ n_4^{*}(k+1)\end{array}\right)---\left(11\right)$

Similarly, the SFBC data that send are merged to the data that receive on direct link on access link, merge equation (9) and (10) and obtain as follows:

$\left(\begin{array}{c}{y}_1\left(k\right)\\ y_2^{*}(k+1)\\ y_3\left(k\right)\\ y_4^{*}(k+1)\end{array}\right)=\left(\begin{array}{cc}{h}_1\left(k\right)& 0\\ 0& -h_2^{*}\left(k\right)\\ h_{11}\left(k\right)& h_{12}\left(k\right)\\ h_{12}^{*}\left(k\right)& -h_{11}^{*}\left(k\right)\end{array}\right)\left(\begin{array}{c}{s}_1\left(k\right)\\ -s_2^{*}(k+1)\end{array}\right)+\left(\begin{array}{c}{n}_1\left(k\right)\\ n_2^{*}(k+1)\\ n_3\left(k\right)\\ n_4^{*}(k+1)\end{array}\right)---\left(12\right)$

Above being similar to, derive, equation (12) can be expressed as following matrix form:

$\stackrel{\‾}{y}=\stackrel{\‾}{h}\stackrel{\‾}{s}+\stackrel{\‾}{n}---\left(13\right)$

Based on existing SFBC detection algorithm, the packet of transmission can be resumed into:

$\left(\begin{array}{c}{s}_1\left(k\right)\\ -s_2^{*}(k+1)\end{array}\right)=\frac{1}{{\left|h_1\left(k\right)\right|}^2+{\left|h_{11}\left(k\right)\right|}^2+{\left|h_{12}\left(k\right)\right|}^2}{\stackrel{\‾}{h}}^{*}\stackrel{\‾}{y}---\left(14\right)$

Cooperating relay based on SFBC is carried out to emulation.The setting parameter of emulation is as given in table 1.As can be seen from Figure 9, when BLER=2 * 10 ^-3time, uneven by compensation power, be compared to distributed SFBC, performance is approximately improved 4.0dB.

In order to verify proposed scheme, systematic function has also been carried out to emulation.Figure 10 has drawn the simulation deployment figure of system.The network of sectorized cells forms with 7 communities and each community comprises 3 sectors.In each sector, be deployed with two trunk desks apart from BS2/3 radius of society.At simulation parameter shown in table 2.

Table 2

Figure 11 shows simulation result.As can be seen from the figure, in distributed SFBC system, the Signal to Interference plus Noise Ratio (SINR) of 40% MS is 15dB, and the SINR of the MS of method 40% proposed by the invention reaches 18dB, this explanation performance gain is about 3dB, this is that path-loss difference changes statically because mobile subscriber is positioned at different positions, but in each position, power back-off provides improved SINR gain adaptively, so the performance of system will be enhanced.

Below by reference to the accompanying drawings a plurality of execution modes of the present invention are described.It should be noted that for the present invention is easier to understand, description has above been omitted to be known for a person skilled in the art and may to be essential some ins and outs more specifically for realization of the present invention.

The present invention can take the form that complete hardware is realized, the realization of hardware cell and software unit is realized or comprised simultaneously to software completely.In a preferred embodiment, the present invention realizes with software, and this software includes but not limited to firmware, resident software, microcode etc.

The object that specification of the present invention is provided is in order to illustrate and to describe, rather than is used for exhaustive or limits the invention to disclosed form.For those of ordinary skill in the art, many modifications and changes are all apparent.

Therefore; selecting and describing embodiment is in order to explain better principle of the present invention and practical application thereof; and those of ordinary skills are understood, do not departing under the prerequisite of essence of the present invention, within all modifications and change all fall into protection scope of the present invention defined by the claims.

Claims (17)

1. for a method for wireless communication system cooperating relay, described method comprises:

Via repeated link, receive the packet sending from transmitting apparatus;

According to the difference power between the trunk desk of cooperation, adjust adaptively and will via access link, send to the data packet format of receiving equipment, to the packet receiving from transmitting apparatus via direct link is merged with the packet receiving from the low access link power relay platform cooperating via described access link at receiving equipment place, and realizes the space diversity between the trunk desk cooperating; And

Via access link, packet is sent to described receiving equipment.

2. method according to claim 1, wherein determines according to the channel quality feedback information receiving from receiving equipment high access link power relay platform and the low access link power relay platform that has difference power.

3. method according to claim 1, wherein said adjustment adaptively comprises that the data packet format that keeps described low access link power relay platform to receive from described transmitting apparatus via repeated link is constant, and the data packet format that the high access link power relay of adaptively modifying platform receives from described transmitting apparatus via repeated link, so that the data packet format that sends to described receiving equipment from the trunk desk of cooperation meets the criterion of space diversity coding.

4. method according to claim 3, wherein said space diversity coding is space-time block coding or Space Frequency Block Coding.

5. method according to claim 4, wherein said space-time block coding or described Space Frequency Block Coding are the Alamouti codes that meets the requirement of the data packet format sending via access link.

6. for a trunk desk for wireless communication system cooperating relay, described trunk desk comprises:

Receiving system, for receiving the packet sending from transmitting apparatus via repeated link;

Adjusting device, be used for according to the difference power between the trunk desk of cooperation, adjust adaptively and will via access link, send to the data packet format of receiving equipment, to the packet receiving from transmitting apparatus via direct link is merged with the packet receiving from the low access link power relay platform cooperating via access link at receiving equipment place, and realizes the space diversity between the trunk desk cooperating; And

Dispensing device, for sending to described receiving equipment via access link by packet.

7. trunk desk according to claim 6, wherein said adjusting device is determined high access link power relay platform and the low access link power relay platform that has difference power according to the channel quality feedback information receiving from receiving equipment.

8. trunk desk according to claim 6, wherein said adjusting device is constant for the data packet format that keeps described low access link power relay platform to receive from described transmitting apparatus via repeated link, and the data packet format that the high access link power relay of adaptively modifying platform receives from described transmitting apparatus via repeated link, so that the data packet format that sends to described receiving equipment from the trunk desk of cooperation meets the criterion of space diversity coding.

9. trunk desk according to claim 8, wherein said space diversity coding is space-time block coding or Space Frequency Block Coding.

10. trunk desk according to claim 9, wherein said space-time block coding or described Space Frequency Block Coding are the Alamouti codes that meets the requirement of the data packet format sending via access link.

11. 1 kinds of methods for wireless communication system cooperating relay, described method comprises:

Via direct link, receive the packet sending from transmitting apparatus and via access link, receive the packet sending from the trunk desk of cooperation;

The described packet receiving via direct link is merged with the packet receiving from the low access link power relay platform cooperating via access link, wherein the trunk desk of cooperation, according to mutual difference power, is adjusted adaptively and will be sent to the data packet format of receiving equipment via access link to realize the space diversity between the trunk desk of described merging and cooperation.

12. methods according to claim 11, the packet wherein receiving from transmitting apparatus has identical data packet format with the packet receiving from low access link power relay platform, and the packet receiving from high access link power relay platform has through described trunk desk adaptively modifying to meet the encode data format of criterion of the space diversity of the trunk desk of cooperation.

13. methods according to claim 11, wherein said merging is used high specific to merge the packet to receiving via direct link and the packet that receives via low-power access link merges.

14. 1 kinds of receiving equipments for wireless communication system cooperating relay, described receiving equipment comprises:

Receiving system, for receiving the packet sending from transmitting apparatus and receiving the packet sending from the trunk desk of cooperation via access link via direct link;

Merge device, for the described packet receiving via direct link is merged with the packet receiving from the low access link power relay platform cooperating via access link, wherein the trunk desk of cooperation, according to mutual difference power, is adjusted adaptively and will be sent to the data packet format of receiving equipment via access link to realize the space diversity between the trunk desk of described merging and cooperation.

15. receiving equipments according to claim 14, the packet that wherein said receiving system receives from transmitting apparatus has identical data packet format with the packet receiving from low access link power relay platform, and the packet receiving from high access link power relay platform has through described trunk desk adaptively modifying to meet the encode data format of criterion of the space diversity of the trunk desk of cooperation.

16. receiving equipments according to claim 14, wherein said merging device is used high specific to merge the packet to receiving via direct link and the packet that receives via low-power access link merges.

17. 1 kinds of wireless communication systems that use cooperating relay, comprising:

Transmitting apparatus, for sending packet and send packet via repeated link to trunk desk to receiving equipment via direct link;

The trunk desk of cooperation, for receiving via repeated link from the packet of transmitting apparatus and according to the difference power between the trunk desk of cooperation, adjust adaptively and will via access link, send to the data packet format of receiving equipment, to realize the space diversity at the packet merging at receiving equipment place and the trunk desk of cooperation; And

Receiving equipment, merges to obtain access link power identical between access link for the packet that the described packet receiving via direct link is received with low access link power relay platform from cooperation.