CN101414865A - Unite multi-user transmission method for wireless repeater assistance multi-user access system - Google Patents

Abstract

The invention relates to a combined multi-user sending method of an auxiliary multi-user access system of a wireless repeater, which can improve frequency spectrum utilization of uplink multi-user access in a cellular wireless communication system. The system consists of a plurality of user terminals, a wireless repeater and a receiving device. The sending method has the following requirements: firstly, a plurality of users send signals by respective channels and the wireless repeater and the receiving device are in receiving state; and the wireless repeater carries out signal processing to the signals of a plurality of users and then sends the processed signals to the receiving device. The combined multi-user sending method of the wireless repeater comprises two types: the first types is as follows: the received signals of a plurality of users carries out linear superposition and then is amplified and is forwarded to the receiving device; and the second type is as follows: the wireless repeater carries out detection to the information of a plurality users, and if the detection is successful, the information of a plurality of users carries out multi-user combined coding and modulation and then is sent to the receiving equipment.

Description

The associating multi-user delivery method of the auxiliary multi-user access system of wireless repeater

Technical field

The present invention is the method that a kind of multi-user who is applied to wireless communication system inserts, and belongs to the multi-user communication technical field in the radio communication.

Background technology

Wireless relay can make full use of the spectrum efficiency that space resources can improve system.The basic ideas that adopt the wireless relay networking are to introduce some wireless relay nodes (RS) between original base station (BS) and user terminal (UE), thereby improve the uniformity that whole wireless network electric wave distributes, make that the availability of frequency spectrum at cell edge place and power utilization are improved largely.Traditional wireless repeater only is used for transmitting the information of unique user.In order to support the multi-user, adopt the mode of time-division or frequency division usually.As shown in Figure 1, UE1, UE2 are related with RS.In order to support the multi-user, traditional wireless repeater adopts following time-division sending method: at first time slot, UE1 broadcasting, RS and BS receive, second time slot, RS arrives BS to the signal forwarding that receives, at the 3rd time slot, UE2 broadcasting, RS and BS receive, the 4th time slot, RS arrives BS to the signal forwarding that receives.Certainly, also can adopt the mode of frequency division to send: at first time slot, 1 broadcasting of UE1 band occupancy, 2 broadcasting of UE2 band occupancy, RS and BS receive, second time slot, RS is forwarded to BS to the signal that receives respectively on different frequency range.This two kinds of methods implement simpler, but the total availability of frequency spectrum of system is not high.Document [Y.Chen, S.Kishore, and J.Li, ＂ Wireless diversity through network coding ＂, in Proceedings of IEEE Wireless Communicationsand Networking Conference, 2006, Vol.3, pp.1681-1686.] the XOR network code is applied to the auxiliary multi-user access system of wireless repeater, thereby improves the diversity ability of system, but the performance improvement of this method is limited.The present invention proposes to adopt associating multi-user delivery method at wireless repeater, fully excavates the space resources that wireless repeater brought thereby improve, thus the total spectrum efficiency of raising system.The method and the XOR network code that propose contrast, and the result shows that the method for proposition is much better than the XOR network code, and the system spectrum utilance is higher than the auxiliary multi-user system of traditional relaying.

Summary of the invention

Technical problem: the objective of the invention is to provide for the auxiliary multi-user wireless communication system of wireless repeater the associating multi-user delivery method of the auxiliary multi-user access system of a kind of wireless repeater, this method can improve the total frequency spectrum utilance that up a plurality of users insert in the cellular radio Communication system.

Technical scheme: the auxiliary multi-user wireless communication system of wireless repeater is made of a plurality of user terminals, a wireless repeater and a receiving equipment.The associating multi-user delivery method of wireless repeater provided by the present invention system specifically comprises the steps:

A. many users transmitting channel by separately sends signal, wireless repeater and receiving equipment received signal;

B. wireless repeater carries out following processing to a plurality of users' signal: carry out to received signal amplifying after the linear superposition; Signal to a plurality of users detects, if detect successfully then a plurality of users' signal is carried out multi-user association coding and digital modulation;

C. wireless repeater sends to receiving equipment to the signal after handling.

Described a plurality of user transmitting channel separately is the different time-gap during time division multiple access inserts, or the different frequency bands of frequency division multiple access in inserting and different code channels during code division multiple access inserts, or the combination of above-mentioned time slot, frequency band and code channel.

Described a plurality of user transmitting channel separately is identical time slot and the frequency band during time division multiple access inserts, or identical time slot and frequency band in the frequency division multiple access access, or identical code channel in the code division multiple access access, or the combination of above-mentioned time slot, frequency band and code channel.

Signal to a plurality of users detects, if detect successfully then the method that a plurality of users' signal carries out multi-user association coding and digital modulation comprised: each user's signal is carried out digital modulation, modulation symbol to all users carries out linear superposition then, or with a plurality of users' signal through and the string conversion after the digital modulation of uniting, or with a plurality of users' signal through and the string conversion, carry out error correction coding and interweave, carry out digital modulation at last.

The method of described digital modulation comprises phase shift keying modulation and quadrature amplitude modulation.

Described error correction/encoding method comprises convolutional encoding, Turbo coding, Reed-Solomon coding, linear block codes and low density parity check code.

Beneficial effect: major advantage of the present invention is, wireless repeater carries out combined coding to a plurality of users' the signal that converges, thereby a plurality of parallel flows are converted into single stream, thereby send to receiving equipment, improve the efficient that wireless repeater is transmitted like this, thereby improved the availability of frequency spectrum of whole system.

The associating multi-user delivery method of the auxiliary multi-user access system of the wireless repeater that the present invention proposes can be applied to the up access of cell mobile communication systems.The user can adopt code division multiple access access, time division multiple access access, frequency division multiple access to insert, and also can adopt the interlacing multi-address in conjunction with OFDM to insert.

Description of drawings

Fig. 1 is the basic comprising schematic diagram of the auxiliary multi-user wireless communication system of wireless repeater.

Fig. 2 is that expression is according to the N user's access of the embodiment of the invention and the reception and the sending method schematic diagram at wireless repeater station.

Fig. 3 represents multi-user association coding embodiment 1.

Fig. 4 represents multi-user association coding embodiment 2.

Fig. 5 represents multi-user association coding embodiment 3.

Fig. 6 represents multi-user association coding embodiment 4.

When Fig. 7 has provided the access of quadrature multiple access, total frequency spectrum utilance (bit/s/Hz) contrast of various schemes.

When Fig. 8 has provided nonopiate multiple access and has inserted, total frequency spectrum utilance (bit/s/Hz) contrast of various schemes.

Embodiment

By reading and understanding the detailed description of the preferred embodiment of the present invention being done below with reference to accompanying drawing, these and other purposes, features and advantages of the present invention will be become apparent.In describing below, receiving equipment is example with the base station, but the method for being invented is not limited in the base station, also can be the terminal of other type.Wherein:

Fig. 1 is the basic comprising of the auxiliary multi-user wireless communication system of wireless repeater: it comprises a BS, a RS, and several user terminals are example with two users among the figure.

Fig. 2 is that expression is according to the N user's access of the embodiment of the invention and the reception and the sending method schematic diagram at wireless repeater station.Transmitting terminal is made of N user terminal, and wireless repeater at first carries out analog-to-digital conversion to the signal that receives, and enters then to amplify to transmit or the decoding forward mode.Amplifying forward mode, sending after amplifying laggard line number mould conversion to received signal.At the decoding forward mode, utilize multi-user detector to detect user's information according to received signal earlier, unite the multi-user then and send, carry out then sending after the digital-to-analogue conversion.

Fig. 3 represents multi-user association coding embodiment 1, and at first carry out and user's transmitting terminal identical operations: promptly each user carries out error correction coding, interweaves then.Next the information after the interweaving of a plurality of users is carried out mould N addition, carry out digital modulation then, send through after the digital-to-analogue conversion at last.

Fig. 4 represents multi-user association coding embodiment 2, promptly the parallel information streams after the interweaving of a plurality of users is united digital modulation, sends through after the digital-to-analogue conversion at last.

Fig. 5 represents multi-user association coding embodiment 3, promptly the information after the interweaving of each user is carried out digital modulation, multiply by a complex factor then respectively, is superimposed then, sends through after the digital-to-analogue conversion at last.

Fig. 6 represents multi-user association coding embodiment 4, promptly a plurality of users' information is united error correction coding, then the bit behind the coding is carried out digital modulation, sends through after the digital-to-analogue conversion at last.

This method comprises the steps:

A. many users transmitting channel by separately sends signal, wireless repeater and receiving equipment received signal;

B. wireless repeater carries out following processing to a plurality of users' signal: carry out to received signal amplifying after the linear superposition; Signal to a plurality of users detects, if detect successfully then a plurality of users' signal is carried out multi-user association coding and digital modulation;

C. wireless repeater sends to receiving equipment to the signal after handling.

Assist the associating multi-user's of multi-user access system sending method to be elaborated to the wireless repeater of the embodiment of the invention with reference to the accompanying drawings.

As one embodiment of the present of invention, at first consider two users' situation.Fig. 1 has provided application scenarios of the present invention under two users' the situation: it comprises a BS, a RS, two user terminals that are in strict synchronism.

At first we provide and adopt the execution mode that amplifies when transmitting (AF) wireless repeater.We consider two kinds of multi-user's access waies: the quadrature multiple access inserts and nonopiate multiple access inserts.

When adopting the quadrature multiple access to insert, for example frequency division multiple access inserts, OFDM inserts or time division multiple access inserts, and the user adopts different channel (time slot or frequency band) to transmit a signal to RS and BS.The received signal of RS and BS can be expressed as,

$y_{\mathrm{RS},U_1}=h_{\mathrm{RS},U_1}{\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_1+n_{\mathrm{RS},1}$ (formula 1)

$y_{\mathrm{RS},U_2}=h_{\mathrm{RS},U_2}{\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_2+n_{\mathrm{RS},2}$ (formula 2)

$y_{\mathrm{BS},{\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_1}=h_{\mathrm{BS},U_1}{\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_1+n_{\mathrm{BS},1}$ (formula 3)

$y_{\mathrm{BS},{\mathrm{<figure-callout\; id="2"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_2}=h_{\mathrm{BS},U_2}{\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_2+n_{\mathrm{BS},2}$ (formula 4)

Wherein, s ₁The transmission symbol of expression UE1,

Expression UE1 is to the channel gain of RS, n _{RS, 1}Noise between expression UE1 and the RS supposes that noise variance is 1, Expression UE1 is to the received signal of RS; s ₂The transmission symbol of expression UE2,

Expression UE2 is to the channel gain of RS, n _{RS, 2}Noise between expression UE2 and the RS supposes that noise variance is 1,

Expression UE2 is to the received signal of RS;

Expression UE1 is to the channel gain of BS, n _{BS, 1}Noise between expression UE1 and the BS supposes that noise variance is 1,

Expression UE1 is to the received signal of BS;

Expression UE2 is to the channel gain of BS, n _{BS, 2}Noise between expression UE2 and the BS supposes that noise variance is 1,

Expression UE2 is to the received signal of BS.

Receive all users' signal as RS after, carry out linear superposition, amplify then and send to BS.The signal y that BS receives _{BS, RS}Can be expressed as,

$y_{\mathrm{BS},\mathrm{RS}}={\mathrm{\&alpha;h}}_{\mathrm{BS},\mathrm{RS}}(h_{\mathrm{RS},U_1}{\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_1+h_{\mathrm{RS},U_2}{\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_2+n_{\mathrm{RS},1}+n_{\mathrm{RS},2})+n_{\mathrm{BS},\mathrm{RS}}$ (formula 5)

Wherein, α is an amplification factor, h _{BS, RS}Expression RS is to the channel gain of BS, n _{BS, RS}Noise between expression RS and the BS closes the form of being write as matrix vector with (formula 3) (formula 4) and (formula 5),

$\left[\begin{array}{c}{y}_{\mathrm{BS},U_1}\\ y_{\mathrm{BS},U_2}\\ y_{\mathrm{BS},\mathrm{RS}}\end{array}\right]=\left[\begin{array}{cc}{h}_{\mathrm{BS},U_1}& 0\\ 0& h_{\mathrm{BS},U_2}\\ {\mathrm{\&alpha;h}}_{\mathrm{BS},\mathrm{RS}}{h}_{\mathrm{RS},U_1}& {\mathrm{\&alpha;h}}_{\mathrm{BS},\mathrm{RS}}{h}_{\mathrm{RS},U_2}\end{array}\right]\left[\begin{array}{c}{s}_1\\ {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_2\end{array}\right]+\left[\begin{array}{c}{n}_{\mathrm{BS},1}\\ n_{\mathrm{BS},2}\\ {\mathrm{\&alpha;h}}_{\mathrm{BS},\mathrm{RS}}(n_{\mathrm{RS},1}+n_{\mathrm{RS},2})+n_{\mathrm{BS},\mathrm{RS}}\end{array}\right]$ (formula 6)

BS can adopt the method for various Multiuser Detection to obtain each user's transmission signal.

When two users adopt nonopiate access way, for example take identical running time-frequency resource, at the received signal y of RS and BS _RSAnd y _{BS, U}Be expressed as,

$y_{\mathrm{RS}}=h_{\mathrm{RS},U_1}{\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_1+h_{\mathrm{RS},U_2}{\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_2+n_{\mathrm{RS}}$ (formula 7)

$y_{\mathrm{BS},U}=h_{\mathrm{BS},U_1}{\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_1+h_{\mathrm{BS},U_2}{\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_2+n_{\mathrm{BS},1}$ (formula 8)

Be forwarded to BS after the received signal of RS amplified, the transmission signal of the RS that receives of BS is so,

$y_{\mathrm{BS},\mathrm{RS}}={\mathrm{\&alpha;h}}_{\mathrm{BS},\mathrm{RS}}(h_{\mathrm{RS},U_1}{\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_1+h_{\mathrm{RS},U_2}{\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_2+n_{\mathrm{RS}})+n_{\mathrm{BS},\mathrm{RS}}$ (formula 9)

(formula 8) and (formula 9) is merged into matrix form can be expressed as,

$\left[\begin{array}{c}{y}_{\mathrm{BS},U}\\ y_{\mathrm{BS},\mathrm{RS}}\end{array}\right]=\left[\begin{array}{cc}{h}_{\mathrm{BS},U_1}& h_{\mathrm{BS},U_2}\\ {\mathrm{\&alpha;h}}_{\mathrm{BS},\mathrm{RS}}{h}_{\mathrm{RS},U_1}& {\mathrm{\&alpha;h}}_{\mathrm{BS},\mathrm{RS}}{h}_{\mathrm{RS},U_2}\end{array}\right]\left[\begin{array}{c}{s}_1\\ {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_2\end{array}\right]+\left[\begin{array}{c}{n}_{\mathrm{BS},1}\\ {\mathrm{\&alpha;h}}_{\mathrm{BS},\mathrm{RS}}{n}_{\mathrm{RS}}+n_{\mathrm{BS},\mathrm{RS}}\end{array}\right]$ (formula 10)

BS can adopt the method for various Multiuser Detection to obtain each user's transmission signal.

When RS has decoding when transmitting the function of (DF), no matter a plurality of users adopt quadrature to insert still nonopiate access, all suppose the information that RS can each user of decoding success below.RS carries out the coding identical with transmitting terminal, interweaves each user's information, carries out multi-user association coding and modulation then.The effect that multi-source merges has been played in multi-user association coding here and modulation.Provided the embodiment of several typical multi-user association codings and modulation below.

Embodiment 1: XOR (XOR) mode.The XOR mode is by document [Y.Chen, S.Kishore, and J.Li, ＂ Wirelessdiversity through network coding ＂, in Proceedings of IEEE Wireless Communications andNetworking Conference, 2006, Vol.3, pp.1681-1686.] propose, its thought is: a plurality of parallel informations after subscriber-coded are carried out symbol-modulated through after the add operation of Galois field, as shown in Figure 3.A simple example is, two users' coded-bit is carried out modulating after the XOR computing.This is to be traditional linear network encoding.This embodiment will weigh the superiority of the invention of proposition as a kind of contrast benchmark.

Embodiment 2: the multi-user association modulation.Adopt the thought of multi-user association modulation to be: the sign map that a plurality of parallel informations after subscriber-coded are united, as shown in Figure 4.A simple example is that a plurality of users' coded-bit is united high order modulation.

Embodiment 3: the symbol after each user's modulation is carried out linear superposition.Its basic thought is: after each user's process is encoded, interweaves and modulated, multiply by a complex factor, their stack backs are sent, as shown in Figure 5.

Embodiment 4: associating multi-user error correction coding, as shown in Figure 5.Its basic thought is: a plurality of users' information bit through and string conversion, carry out error correction coding then, send after advancing ovennodulation then.The error correction coding here can be any error correction coding, for example convolution code, Turbo code, linear block codes and low density parity check code (LDPC) etc.

Introduce the reception programme of various examples below respectively.

Here we consider that BS adopts the Turbo receiver.If complexity is had relatively high expectations, can only once decipher, be non-iterative receiver.We are example with the nonopiate access of two users, provide detection and interpretation method at above-mentioned four kinds of option b S.But this method that provides can be generalized to the situation of a plurality of users and quadrature access.

The method of reseptance of embodiment 1: when adopting XOR, the output of the maximum likelihood soft inputting and soft of BS detects.(formula 8) formula is represented two users' that BS receives signal, and the signal of the RS that BS receives can be expressed as,

y _{BS, RS}=h _{BS, RS}s ₃+ n _{BS, 2}(formula 11)

Here suppose s ₃Be s ₁And s ₂New modulation symbol after pairing two user's bit informations process XOR computing, and the variance of hypothesis additive Gaussian noise is 1.So according to (formula 8) and (formula 11), during the employing Maximum Likelihood Detection, the bit soft information that can obtain sending the user is,

$L_k^e=\underset{d:d_k=1}{\max }\{-{|y_{\mathrm{BS},U}-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_1}\mathrm{\&alpha;}\left(d_1\right)-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="2"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_2}\mathrm{\&alpha;}\left(d_2\right)|}^2-{|y_{\mathrm{BS},\mathrm{RS}}-h_{\mathrm{RS},\mathrm{RS}}\mathrm{\&beta;}\left(d\right)|}^2+({2d}_{\left[k\right]}-1)l_{\left[k\right]}^a\}$

$+\underset{d:d_k=0}{\max }\{{|y_{\mathrm{BS},U}-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_1}\mathrm{\&alpha;}\left(d_1\right)-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="2"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_2}\mathrm{\&alpha;}\left(d_2\right)|}^2+{|y_{\mathrm{BS},\mathrm{RS}}-h_{\mathrm{RS},\mathrm{RS}}\mathrm{\&beta;}\left(d\right)|}^2+({2d}_{\left[k\right]}-1)l_{\left[k\right]}^a\}$

(formula 12)

Wherein, $d=\left[\begin{array}{c}{d}_1\\ {\mathrm{<figure-callout\; id="2"\; label="d"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">d</figure-callout>}}_2\end{array}\right]$ Be expression [s ₁s ₂] ^TPairing bit vectors, they discharge d according to user 1 to user's 2 orders ₁And d ₂Be respectively s ₁And s ₂Corresponding bit vectors.α (d ₁) represent bit vectors is mapped to modulation symbol, suppose that here user 1 and user 2 adopt identical modulation system.β (d) then represents the modulation symbol of bit vectors d correspondence when adopting the XOR linear network encoding, d _[k]Expression vector d deletes the vector of k bit correspondence.l ^aThe pairing prior information of expression bit vectors d is represented with log-likelihood ratio.

Expression vector l ^aDelete the vector of k bit correspondence.If do not need decoding feedback iteration, then can be with l ^aBe changed to zero vector.

Detecting the bit likelihood ratio of output can use for each user's decoder, and the external application information of decoding feedback can be used for (formula 12) formula, thereby finishes the Turbo iteration.

The method of reseptance of embodiment 2: when adopting the multi-user association modulation, maximum likelihood joint-detection and the example 1 of BS are similar, only are in (formula 12) formula, and β (d) is the pairing high order modulation symbol of vector d.

The signal of the RS that the method for reseptance of embodiment 3: BS receives can be expressed as,

y _{BS, RS}=h _{BS, RS}(λ ₁s ₁+ λ ₂s ₂)+n _{BS, 2}(formula 13)

Wherein, λ ₁And λ ₂Be complex factor.(formula 8) and (formula 13) is merged into matrix form can be expressed as,

$\left[\begin{array}{c}{y}_{\mathrm{BS},U}\\ y_{\mathrm{BS},\mathrm{RS}}\end{array}\right]=\left[\begin{array}{cc}{h}_{\mathrm{BS},U_1}& h_{\mathrm{BS},U_2}\\ h_{\mathrm{BS},\mathrm{RS}}{\mathrm{\&lambda;}}_1& {\mathrm{\&lambda;}}_2{h}_{\mathrm{BS},\mathrm{RS}}\end{array}\right]\left[\begin{array}{c}{s}_1\\ {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">s</figure-callout>}}_2\end{array}\right]+\left[\begin{array}{c}{n}_{\mathrm{BS},1}\\ n_{\mathrm{BS},2}\end{array}\right]$ (formula 14)

Similar two two MIMO that receive of mathematical relationship between the transmitting-receiving, BS can adopt following maximum likelihood soft inputting and soft output to detect,

$L_k^e=\underset{d:d_k=1}{\max }\{-{|y_{\mathrm{BS},U}-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_1}\mathrm{\&alpha;}\left(d_1\right)-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="2"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_2}\mathrm{\&alpha;}\left(d_2\right)|}^2-{|y_{\mathrm{BS},\mathrm{RS}}-h_{\mathrm{BS},\mathrm{RS}}{\mathrm{\&lambda;}}_1\mathrm{\&alpha;}\left(d_1\right)-{\mathrm{\&lambda;}}_2{h}_{\mathrm{BS},\mathrm{RS}}\mathrm{\&alpha;}\left(d_2\right)|}^2+({2d}_{\left[k\right]}-1)l_{\left[k\right]}^a\}$

$+\underset{d:d_k=0}{\max }\{{|y_{\mathrm{BS},U}-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_1}\mathrm{\&alpha;}\left(d_1\right)-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="2"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_2}\mathrm{\&alpha;}\left(d_2\right)|}^2+{|y_{\mathrm{BS},\mathrm{RS}}-h_{\mathrm{BS},\mathrm{RS}}{\mathrm{\&lambda;}}_1\mathrm{\&alpha;}\left(d_1\right)-{\mathrm{\&lambda;}}_2{h}_{\mathrm{BS},\mathrm{RS}}\mathrm{\&alpha;}\left(d_2\right)|}^2-({2d}_{\left[k\right]}-1)l_{\left[k\right]}^a\}$

(formula 15)

The method of reseptance of embodiment 4: when adopting associating multi-user error correction coding, can adopt method of reseptance as shown in Figure 8.At first, the signal that send from a plurality of users carries out Multiuser Detection at BS, can recover the information bit of multi-user association error correction coding, and the judgement of the check digit information that sends from RS can obtain after BS is by demodulation.Both are input to soft inputting and soft output associating multi-user decoder, and the soft information of the information bit of output is input to each user's decoder again and deciphers.If the mode that adopts Turbo to receive can pass to multi-user detector with the soft information of the feedback of single user decoder, thereby finish the Turbo iteration.

In reality realized, the Multiuser Detection of RS was carried out at (formula 7) formula, and it can realize by following formula,

$L_k^e=\underset{d:d_k=1}{\max }\{-{|y_{\mathrm{BS},U}-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_1}\mathrm{\&alpha;}\left(d_1\right)-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="2"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_2}\mathrm{\&alpha;}\left(d_2\right)|}^2+({2d}_{\left[k\right]}-1)l_{\left[k\right]}^a\}$

$+\underset{d:d_k=0}{\max }\{{|y_{\mathrm{BS},U}-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_1}\mathrm{\&alpha;}\left(d_1\right)-h_{\mathrm{BS},{\mathrm{<figure-callout\; id="2"\; label="U"\; filenames="A200810234363E00103.png,A200810234363E00111.png"\; state="\{\{state\}\}">U</figure-callout>}}_2}\mathrm{\&alpha;}\left(d_2\right)|}^2-({2d}_{\left[k\right]}-1)l_{\left[k\right]}^a\}$

(formula 16)

In order to embody practical application effect of the present invention, we provide the emulation of using the performance of system behind the present invention.The condition of emulation is: system is configured to a BS, a RS, and two users all adopt single antenna.User 1 and user's 2 polar coordinates are respectively (1, π/12) and (1 ,-π/12).The position of RS is (0.5,0), and BS is at center of housing estate.Suppose that the exponential damping factor is 3.7, does not consider shadow fading.During emulation, set the signal to noise ratio at cell boarder place, can calculate the user to RS according to this, the user is to BS, and RS is to the path loss of BS.The simulation parameter of system platform is as follows: channel model adopts M.1225 mobile environment A channel, carrier frequency 2GHz, and 60 kilometers of the speed of a motor vehicle are per hour, system bandwidth 20MHz, transmission plan is an OFDM, and subcarrier spacing is 15kHz, and sample frequency is 30.72MHz, the size of fast fourier transform is 2048, each user's Resource Block is 24 x 7, and each Resource Block subcarrier number is 12, and basic modulation system is QPSK, the Turbo code code check is 1/2, and generator polynomial is [1 011; 110 1], the maximum posteriori decoding of logarithm is adopted in decoding, and channel estimating is that ideal communication channel is estimated.

When adopting two users to adopt quadrature to insert, transmit wireless repeater (four time slot or frequency band) and DF wireless repeater embodiment 1 be basic reference point, several schemes below contrasting: AF wireless repeater multi-user association sending method, DF wireless repeater embodiment 2, DF wireless repeater embodiment 3 and DF wireless repeater embodiment 4 that the present invention provides with tradition decoding.Among the embodiment 1, two users' coded-bit carries out carrying out the QPSK modulation behind the XOR, among the embodiment 2, two users' coded-bit is united the 16QAM modulation, and among the embodiment 3, two users' coded-bit carries out the QPSK modulation respectively, superpose then, the stack coefficient is, exp (i*pi/4) and 1, and two users' coded-bit carries out 1/2 error correction coding and modulates through 16QAM then among the embodiment 4.In emulation, when the RS decoding failure, the mode that adopts amplification of the present invention to transmit.Fig. 7 provides system's total frequency spectrum utilance contrast of above-mentioned several schemes.As can be seen, greater than behind-the 1dB, total frequency spectrum utilance of the present invention all is higher than conventional wireless repeater scheme and the existing XOR scheme of document in signal to noise ratio.When adopting two users to adopt nonopiate access, still transmit wireless repeater and DF wireless repeater embodiment 1 is basic reference point, contrast several scheme of the present invention with tradition decoding.Can find out obviously that from Fig. 8 greater than behind-the 1dB, total frequency spectrum utilance of the present invention is a times of conventional wireless repeater, improves very obvious in signal to noise ratio.

Claims (6)

1, the associating multi-user delivery method of the auxiliary multi-user access system of a kind of wireless repeater is characterized in that this method comprises the steps:

A. many users transmitting channel by separately sends signal, wireless repeater and receiving equipment received signal;

B. wireless repeater carries out following processing to a plurality of users' signal: carry out to received signal amplifying after the linear superposition; Signal to a plurality of users detects, if detect successfully then a plurality of users' signal is carried out multi-user association coding and digital modulation;

C. wireless repeater sends to receiving equipment to the signal after handling.

2, the associating multi-user delivery method of the auxiliary multi-user access system of wireless repeater according to claim 1, it is characterized in that described a plurality of user transmitting channel separately is the different time-gap during time division multiple access inserts, or the different frequency bands of frequency division multiple access in inserting and different code channels during code division multiple access inserts, or the combination of above-mentioned time slot, frequency band and code channel.

3, the associating multi-user delivery method of the auxiliary multi-user access system of wireless repeater according to claim 1, it is characterized in that described a plurality of user transmitting channel separately is identical time slot and the frequency band during time division multiple access inserts, or identical time slot and frequency band in the frequency division multiple access access, or identical code channel in the code division multiple access access, or the combination of above-mentioned time slot, frequency band and code channel.

4, the associating multi-user delivery method of the auxiliary multi-user access system of wireless repeater according to claim 1, it is characterized in that a plurality of users' signal is detected, if detect successfully then the method that a plurality of users' signal carries out multi-user association coding and digital modulation comprised: each user's signal is carried out digital modulation, modulation symbol to all users carries out linear superposition then, or with a plurality of users' signal through and the string conversion after the digital modulation of uniting, or with a plurality of users' the signal process and the conversion of going here and there, carry out error correction coding and interweave, carry out digital modulation at last.

5, the associating multi-user delivery method of the auxiliary multi-user access system of wireless repeater according to claim 4 is characterized in that the method for described digital modulation comprises phase shift keying modulation and quadrature amplitude modulation.

6, the associating multi-user delivery method of the auxiliary multi-user access system of wireless repeater according to claim 4 is characterized in that described error correction/encoding method comprises convolutional encoding, Turbo coding, Reed-Solomon coding, linear block codes and low density parity check code.

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