CN101232692A - Multi-user detecting method and device in wireless communication network - Google Patents

Abstract

The invention provides a multi-user detection method and a device thereof in wireless network. Specifically, the adopted technical scheme of the invention is as follows: jointly detecting and processing an original signal on the basis of a first estimated value of user signals from each user in a receiving device; de-multiplexing a second estimated value obtained from the joint detection; multiplexing the second estimated value obtained from the de-multiplexing; and repeating the operation until the iteration is convergent or reaches set times. The invention accumulates precision estimated by Gauss during many times of iteration, thus providing a multi-user detection scheme superior to prior art and optimizing uplink performance.

Description

Multi-user test method in the cordless communication network and device thereof

Technical field

The present invention relates to cordless communication network, relate in particular to the Multiuser Detection in the cordless communication network.

Background technology

In UMTS (universal mobile telecommunications system is a Wideband Code Division Multiple Access (WCDMA) based on the W-CDMA technology), the capacity of dedicated uplink channels is a bottleneck of system, and the performance that how to improve up link always is a problem that receives much attention.Existing multi-user test method based on long scrambler is unsatisfactory among the UMTS, and this has just influenced the performance of up link to a certain extent.

In addition, the existing MUD (multi-user detection device 1) that is used for other system is also because problem separately and can't being incorporated in the UMTS system:

1.CDMA the MUD in (code division multiple access) system is mainly based on spread spectrum and short scrambler, its problem is, computation complexity is higher and do not support long scrambler;

2.IDMA the MUD in (interlacing multi-address) system is mainly based on interleaver, its problem is, need for each subscriber equipment (for simplicity's sake, below " subscriber equipment " being abbreviated as " user ") interleaver that distributes a unique length may reach thousands of chips is used for Multiuser Detection, in addition, the incompatible UMTS of IDMA, and do not support many yards transmission.

Therefore, need a kind of new multi-user test method and device, thereby optimize the performance of UMTS system (up) link.

Summary of the invention

The present invention proposes in order to solve the aforementioned problems in the prior just.

According to a first aspect of the invention, a kind of method that the signal from the multi-user is detected of being used in the receiving equipment of wireless network is provided, this method may further comprise the steps: based on first estimated value from each user's subscriber signal is come primary signal is carried out united detection processing, to generate second estimated value from each user's subscriber signal respectively, wherein said primary signal comprises the subscriber signal from all users; Respectively second estimated value of described subscriber signal from each user is carried out and the corresponding demultiplexing of transmitting terminal is handled, with the demultiplexing estimated value of the subscriber signal that generates described each user; Respectively the demultiplexing estimated value of described each user's subscriber signal is carried out the signal multiplexing identical with transmitting terminal and handle and do not have, to generate the first new estimated value from each user's subscriber signal; The first new estimated value of described subscriber signal is repeated above-mentioned steps a-c until satisfying predetermined condition as first estimated value.

According to a second aspect of the invention, a kind of multi-user detection device that the signal from the multi-user is detected of being used in the receiving equipment of wireless network is provided, this device comprises: the joint-detection device, be used for based on first estimated value from each user's subscriber signal is come primary signal is carried out united detection processing, to generate second estimated value from each user's subscriber signal respectively, wherein said primary signal comprises the subscriber signal from all users; Deplexing apparatus is used for respectively second estimated value of described subscriber signal from each user is carried out and the corresponding demultiplexing of transmitting terminal is handled, with the demultiplexing estimated value of the subscriber signal that generates described each user; The signal multiplexing device is used for that respectively the demultiplexing estimated value of described each user's subscriber signal is carried out the signal multiplexing identical with transmitting terminal and handles, to generate the first new estimated value from each user's subscriber signal; Control device is used to control described joint-detection device, Deplexing apparatus and signal multiplexing device the first new estimated value of described subscriber signal is repeated above-mentioned processing until satisfying predetermined condition as first estimated value.

According to a third aspect of the present invention, provide a kind of method that auxiliary reception equipment carries out Multiuser Detection that in the transmitter of wireless network, is used for, it is characterized in that, utilized the relevant information that interweaves that prestores to carry out interleaving treatment to sent burst.

According to a fourth aspect of the present invention, a kind of servicing unit that auxiliary reception equipment carries out Multiuser Detection that is used in the transmitter of wireless network is provided, it is characterized in that, utilize the relevant information that interweaves that prestores to carry out interleaving treatment to sent burst.

According to a fifth aspect of the present invention, provide a kind of receiving equipment in wireless network, it is characterized in that, the multi-user detection device that being used for of providing according to a second aspect of the invention detected the signal from the multi-user has been provided.

According to a sixth aspect of the invention, provide a kind of transmitter in wireless network, it is characterized in that, the servicing unit that auxiliary reception equipment carries out Multiuser Detection that is used for that provides according to a fourth aspect of the present invention has been provided.

Adopt method provided by the invention and related device, can realize the Multiuser Detection optimized, to improve the uplink performance of wireless network (for example, UMTS network).

Description of drawings

By reading the detailed description of non-limiting example being done with reference to the following drawings, other features, objects and advantages of the present invention will become more apparent.

Fig. 1 is the wireless network schematic diagram according to a specific embodiment of the present invention;

Fig. 2 is for being used for method flow diagram that the signal from the multi-user is detected according to a specific embodiment of the present invention in the receiving equipment of wireless network shown in Figure 1;

Fig. 3 is for being used for multi-user detection device block diagram that the signal from the multi-user is detected according to a specific embodiment of the present invention in the receiving equipment of wireless network shown in Figure 1;

Fig. 4 is the method schematic diagram that is used for signal is carried out interleaving treatment and deinterleaving processing in multi-user detection device shown in Figure 3 (or transmitter of ustomer premises access equipment) according to a specific embodiment of the present invention;

Fig. 5 is for being used for the method flow diagram that auxiliary reception equipment (being positioned at V place, base station) carries out Multiuser Detection according to a specific embodiment of the present invention in the transmitter of wireless network shown in Figure 1;

Fig. 6 is for being used for the device block diagram that auxiliary reception equipment (being positioned at V place, base station) carries out Multiuser Detection according to a specific embodiment of the present invention in the transmitter of wireless network shown in Figure 1;

Fig. 7 shows the MUD of the present invention's proposition and the performance of existing UMTS compares;

Fig. 8 is the simulation result figure of iteration convergence under the situation of 12 UE;

Fig. 9 has/does not have the approximate simulation result figure of maximum of sequence transformation in the multipath additive white Gaussian noise channel.

Embodiment

Describe the present invention below in conjunction with accompanying drawing.

In the following description, subscriber signal is represented the signal from a user, in addition, should understand neatly " signal " this notion, it both can be understood as the information bit that is used for the both link ends communication between devices that transmitter b sends, can be understood as yet and comprise that above-mentioned information bit also comprises a upperseat concept of (obtaining based on described information bit) other type information simultaneously, tool exclusively can not comprise priori and/or posteriority log-likelihood ratio.

The network configuration explanation

Fig. 1 is the wireless network schematic diagram according to a specific embodiment of the present invention, and this wireless network (for example, the UMTS network) comprises a plurality of user I-IV (for example, mobile phone), in addition, also comprises a base station V.The multi-user detection device 1 that is used for that in receiving equipment a the signal from the multi-user is detected provided by the present invention promptly is disposed at the receiving equipment a of base station V; Correspondingly, servicing unit 2 provided by the invention is disposed among the transmitter b of each subscriber equipment.The application that should be appreciated that multi-user detection device provided by the invention is not limited to the base station, can be applied in the network equipment that any needs carry out Multiuser Detection.Wherein, for simplicity's sake, transmitter b and servicing unit 2 wherein only have been shown in user I.

Among Fig. 1, user I, user II, user III and user IV send subscriber signal based on the W-CDMA technology via the base station V of up channel under it, at base station V, the primary signal that its receiving equipment a receives comprises the superposed signal from above-mentioned each user's subscriber signal.Therefore, base station V need detect by 1 pair of described primary signal of the multi-user detection device among its receiving equipment a, therefrom separates each the road subscriber signal from each user.

Receiving terminal (carry out the network equipment of Multiuser Detection, such as the base station)

Followingly first aspect of the present invention is described in detail with reference to Fig. 2 and in conjunction with Fig. 1.Fig. 2 is for being used for method flow diagram that the signal from the multi-user is detected according to a specific embodiment of the present invention in the receiving equipment a of wireless network shown in Figure 1.This method originates in step S10:

In step S10, after comprising primary signal from each road subscriber signal of user I-IV and arriving the receiving equipment a place of base station V, base station V is based on to from first estimated value of each user's subscriber signal (for example, the priori log-likelihood ratio) comes primary signal is carried out united detection processing, to generate second estimated value respectively from each user's subscriber signal.Need to understand, owing to relate to iteration, therefore, the primary signal that base station V receives can be in each time iteration and the feedback of previous iteration (be described priori log-likelihood ratio, below can the detailed description) joint-detection that fellowship is new.

Particularly, in the present embodiment, be modulated to example with QPSK (quaternary PSK), the transmit chip signal under the non-many yards forms belongs to I/Q, needs to calculate the probability of each reception chip of each user who forms the QPSK signal.

Suppose to have in system K user, then the primary signal that receives of the receiving equipment a of base station V can be expressed as formula (1):

$r_i=\underset{k=1}{\overset{K}{\mathrm{\Σ}}}\underset{l=1}{\overset{L_k}{\mathrm{\Σ}}}{h}_k^l{x}_k^{i-l+1}+n_i---\left(1\right)$

Please understand, detect owing to the present invention is based on chip-level, i represents in the corresponding a plurality of multiple chips that detect processing in the V of base station synchronously of this signal (exactly, this chip) i at this; L _kExpression is from the maximum number of the transmission path of the subscriber signal of user k; h _k ^lExpression is from the complex channel parameter of the l transmission paths of the subscriber signal of user k; n _iBe that average is 0, variance is σ ²Multiple Gaussian noise.

Therefore, rotate the QPSK symbol in mode shown in the formula (2), to obtain the planisphere of matrix pattern:

$r_i=\underset{k=1}{\overset{K}{\mathrm{\Σ}}}\underset{l=1}{\overset{L_k}{\mathrm{\Σ}}}{h}_k^l\frac{(1+j)(1-j)}{2}{x}_k^{i-l+1}+n_i=\underset{k=1}{\overset{K}{\mathrm{\Σ}}}\underset{l=1}{\overset{L_k}{\mathrm{\Σ}}}\frac{h_k^l(1+j)}{\sqrt{2}}{y}_k^{i-l+1}+n_i---\left(2\right)$

Y wherein _k ⁱBe a QPSK symbol, with channel parameter h with standard constellation _k ^lTurn clockwise 45 °, obtain

Its preservation is used for the processing of back.Therefore can obtain formula (3):

Wherein, at the subscriber signal η that pays close attention to from a user (such as user k) _k ^l(i) should regard subscriber signal and the aforementioned n that comprises from other each user as _iAt interior one big noise.According to central-limit theorem, η _k ^l(i) can be approximately a multiple Gaussian random variable well, so its probability density function can be obtained by formula (4):

${\mathrm{pdf}}_k^{l,i}({\mathrm{<figure-callout\; id="1"\; label="x"\; filenames="A20071003675100341.png,A20071003675100351.png"\; state="\{\{state\}\}">x</figure-callout>}}_1,x_2)=\frac{1}{2\mathrm{\&pi;}\sqrt{\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Re}}\right)\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Im}}\right)}}\exp [-\frac{{(x_1-E\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Re}}\right))}^2}{\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Re}}\right)}-\frac{{(x_2-E\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Im}}\right))}^2}{\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Im}}\right)}]---\left(4\right)$

Wherein, subscript " Re " and " Im " and " x ₁" and " x ₂" represent real part and imaginary part respectively.Variable η _k ^l(i) average (E) and the variance (var) of (for the so-called noise from the subscriber signal of user k) are provided by formula (5) and formula (6), should be appreciated that described variance is noise η _k ^l(i) power:

Wherein,

Will With

Replace with With Can obtain E (η _k ^l(i) ^Im, var (η _k ^l(i) ^Im, E (r _i ^Im) and var (r _i ^Im).

According to a specific embodiment of the present invention, in cdma system, Multiuser Detection provided by the invention has the structure of Turbo type, and all users' subscriber signal is carried out joint-detection, particularly, utilize the priori log-likelihood ratio LLR that returns from last loop feedback _PrioriPromptly

With Further estimate each QPSK symbol y _k ⁱAverage and variance (LLR _PrioriProcurement process ask for an interview description to step S11).Particularly, this QPSK symbol y _k ⁱAverage and variance can through type (9a) and formula (9b) obtain:

$E\left\{y_k^{i^{\mathrm{Re}\left(\mathrm{Im}\right)}}\right\}=\tanh \left(\frac{{\mathrm{LLR}}_{\mathrm{priori}}\left[y_k^{i^{\mathrm{Re}\left(\mathrm{Im}\right)}}\right]}{2}\right)---\left(9a\right)$

$\mathrm{var}\left\{y_k^{i^{\mathrm{Re}\left(\mathrm{Im}\right)}}\right\}=1-E^2\left\{y_k^{i^{\mathrm{Re}\left(\mathrm{Im}\right)}}\right\}---\left(9b\right)$

According to a specific embodiment of the present invention, when Multiuser Detection just begins, when promptly iteration does not begin as yet for the first time yet, because therefore the priori log-likelihood ratio that does not return makes in step S10 $E^{y_k^i}=0;$ And ${\mathrm{var}}^{y_k^i}=1.$ Promptly suppose y _k ⁱFor expectation is 0, variance is the noise of 1 (also being that power is 1), carries out the joint-detection first time.

Then, through type (10) and (11) obtain each chip-level QPSK symbol y _k ⁱ, i=1,2 ... the real part of frame (wherein, frame is a simultaneously treated multiple number of chips in multi-user detection device) and the posteriority log-likelihood ratio (LLR of imaginary part _Posterior).

Wherein subscript " 1 " is represented the 1st transmission paths.Utilize maximal index approximate, above-mentioned two formulas can be simplified to following formula (12) and formula (13).

Wherein, $f_k^{l,i}(x_1,x_2)=\frac{{(x_1-E\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Re}}\right))}^2}{\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Re}}\right)}+\frac{{(x_2-E\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Im}}\right))}^2}{\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Im}}\right)}.$ Emulation shows that formula (12) and formula (13) provide cotype (10) and formula (11) capacity about the same, and therefore, this is approximate to be effective.

Calculating is before all carried out respectively at each bars transmission path, below merges the pairing posteriority log-likelihood ratio that is obtained by formula (12) and (13) of mulitpath based on RAKE receiver:

${\mathrm{LLR}}_{\mathrm{post}}^{\mathrm{RAKE}}\left[y_k^{i^{\mathrm{Re}}}\right]=\underset{l=1}{\overset{L_k}{\mathrm{\&Sigma;}}}{\mathrm{LLR}}_{\mathrm{post}}^l\left[y_k^{i^{\mathrm{Re}}}\right]$ With ${\mathrm{LLR}}_{\mathrm{post}}\left[y_k^{i^{\mathrm{Im}}}\right]=\underset{l=1}{\overset{L_k}{\mathrm{\&Sigma;}}}{\mathrm{LLR}}_{\mathrm{post}}^l\left[y_k^{i^{\mathrm{Im}}}\right]---\left(14\right)$

Use it for subsequent treatment then, represent with plural form as the formula (15):

${\mathrm{LLR}}_{\mathrm{post}}^{\mathrm{RAKE}}\left[y_k^i\right]={\mathrm{LLR}}_{\mathrm{post}}\left[y_k^{i^{\mathrm{Re}}}\right]+j{\mathrm{LLR}}_{\mathrm{post}}\left[y_k^{i^{\mathrm{Im}}}\right]---\left(15\right)$

The specific embodiment of the present invention under the non-many yards transmission has more than been described.Because many yards transmission (it is that the orthogonal spectrum expansion factor is come synchronously transmission signals that a plurality of Dedicated Physical Data Channels adopt different OVSF) are the features of UMTS, therefore, multi-user detection device provided by the invention and method thereof are also supported many yards transmission.Certainly, this method also is applicable to QAM (quadrature amplitude modulation) modulation, therefore also can be used for the HSUPA (high speed uplink packet access) in WCDMA (Wideband Code Division Multiple Access (WCDMA)) system.

Suppose that user k transmits with many coding modes, then formula (1)-(5) stand good.Because for multi-user detection device 1, the employed scrambler of each user is known, and multi-user detection device 1 is easy to just know y _k ⁱWhich part by six parallel sign indicating numbers multiplexing (be real part, or imaginary part).Therefore, by using respectively

With Replace y _k ⁱBe re-used the part average and variance, can calculate the posteriority log-likelihood ratio, wherein subscript " u " refers to the sub-DPDCH in u rank (Dedicated Physical Data Channel),

Be these u rank sub-DPDCH spreading code laminar flows, by with the similar step of formula (9), can obtain

With

Therefore, each chip among the sub-DPDCH

, i=1,2 ... the posteriority log-likelihood ratio of frame (" frame " is illustrated in the number of simultaneously treated continuous plural chip among the V of base station) can be drawn by formula 16 and 17.

Wherein symbol " | Re " refers to that many yards transmission are positioned at the real part of QPSK symbol.With With

Replace

With

Can obtain LLR _Post ^l[z _{K, u} ⁱ| Im] and Such scheme also can utilize maximal index to be similar to simplify, and emulation shows that described maximal index is approximate can provide the performance that is close with such scheme.

Utilize RAKE receiver can obtain { LLR from merging that all transmission paths come with user k information corresponding _Post ^RAKE[z _{K, u} ^l| Re] } _I=1 ^FrameWith (or { LLR _Post ^RAKE[z _{K, u} ^l| Im] } _I=1 ^FrameWith

), so far, generated second estimated value (in this specific embodiment, described second estimated value is the posteriority log-likelihood ratio) from each user's subscriber signal, then enter step S11:

In step S11, the posteriority log-likelihood ratio from each user's subscriber signal that multi-user detection device 1 obtains step S10 respectively carries out and the corresponding demultiplexing of transmitting terminal is handled, with the demultiplexing estimated value of the subscriber signal that generates described each user.According to a specific embodiment of the present invention, described demultiplexing is handled and is comprised descrambling reconciliation spread processing, and according to a preferred embodiment of the present invention, described demultiplexing processing comprises descrambling, separates spread spectrum and deinterleaving processing.Particularly, described demultiplexing is handled by following process and is realized:

If { s _k ⁱ} _I=1 ^FrameThe multiple scrambler sequence of when user side carries out scrambling to signal, using for user k.Because the QPSK signal that receives has been turned clockwise 45 ° in step S10, therefore, use

The posteriority log-likelihood ratio that descrambling obtains from step S10;

The LLR of plural number QPSK symbols streams is mapped to two DTCH (Dedicated Traffic Channel), and being mapped among the DPDCH (Dedicated Physical Data Channel) is { LLR _Post ^RAKE[α _k ⁱ] _I=1 ^Frame, be { LLR among the DPCCH (Dedicated Physical Control Channel) and be mapped to _Post ^RAKE[b _k ⁱ] _I=1 ^FrameWherein, α _kSignal behind the corresponding transmitting terminal spread spectrum coding on DPDCH; And b _kThe signal on DPCCH behind the then corresponding transmitting terminal spread spectrum coding.

Persons of ordinary skill in the art may appreciate that in many yards transmission { LLR _Post ^RAKE[z _{K, u} ⁱ] _I=1 ^FrameBe mapped to u rank DPDCH.

Then, described burst through descrambling being carried out soft decoding (Soft Decoding) also is that despreading is handled.Shown in following formula (18) and formula (19):

${\mathrm{LLR}}^{\mathrm{ant}}\left[{\mathrm{\&alpha;}}_k^i\right]=\underset{p=(i-1)M_{\mathrm{\&alpha;}}+1}{\overset{{\mathrm{iM}}_{\mathrm{\&alpha;}}}{\mathrm{\&Sigma;}}}{\mathrm{\&omega;}}_k^{p-(i-1)\&times;M_{\mathrm{\&alpha;}}}\&times;{\mathrm{LLR}}_{\mathrm{post}}^{\mathrm{RAKE}}{\left[a_k^p\right]}_{\mathrm{ant}},i=\mathrm{1,2},\&CenterDot;\&CenterDot;\&CenterDot;,\frac{\mathrm{frame}}{M_{\mathrm{\&alpha;}}}---\left(18\right)$

${\mathrm{LLR}}^{\mathrm{ant}}\left[{\mathrm{\&beta;}}_k^i\right]=\underset{p=(i-1)M_{\mathrm{\&beta;}}+1}{\overset{{\mathrm{iM}}_{\mathrm{\&beta;}}}{\mathrm{\&Sigma;}}}{\mathrm{\&upsi;}}_k^{p-(i-1)\&times;M_{\mathrm{\&beta;}}}\&times;{\mathrm{LLR}}_{\mathrm{post}}^{\mathrm{RAKE}}{\left[b_k^p\right]}_{\mathrm{ant}},i=\mathrm{1,2},\&CenterDot;\&CenterDot;\&CenterDot;,\frac{\mathrm{frame}}{M_{\mathrm{\&beta;}}}---\left(19\right)$

ant＝1，2，...ANT

Wherein, " α _k" signal before the spread spectrum coding of corresponding transmitting terminal on DPDCH, and " β _k" the preceding signal on DPCCH of corresponding transmitting terminal spread spectrum coding; M is the spreading factor on the respective channel; " ant " and " ANT " represents certain reception antenna in the multi-antenna structure and the sum of reception antenna respectively, subscript " ^l" refer to the 1st reception antenna.Understand easily, in many yards transmission, use

M _γAnd z _{K, u} ^pReplace respectively

M _αAnd α _k ^pAfter, can obtain LLR ^Ant[γ _{K, u} ⁱ], wherein, γ ⁱ _{K, μ}Signal on corresponding transmitting terminal each DPDCH before spread spectrum coding, and ω _kBe channel code, so far, step S11 has finished the demultiplexing to signal;

If described receiving equipment a only comprises a reception antenna, then can directly enter S12; If described receiving equipment a comprises a plurality of reception antennas, then also need the demultiplexing estimated value (through the posteriority log-likelihood ratio of demultiplexing) of pairing each user's of a plurality of reception antennas same signal is merged, with the merging estimated value of the subscriber signal that generates each user.Particularly, utilize following formula that the posteriority log-likelihood ratio through demultiplexing in step S11 is made up:

LLR[u]＝∑ _{1≤ant≤ANT}LLR ^ant[u]

Wherein variable u represents α in non-many yards transmission _k ⁱAnd β _k ⁱ, in many yards transmission, represent γ _{K, u} ⁱAnd β _k ⁱBy collecting the information of coming, and it is made up estimate some bits, observe more confirmation, only need iteration loop seldom just can estimate to restrain a stage from a plurality of reception antennas.After merging, enter step S12;

In substep S12, described demultiplexing estimated value (corresponding single reception antenna) or merging estimated value (corresponding multiple receive antenna) are carried out the signal multiplexing processing, to generate new priori log-likelihood ratio, be used for power and variance in as the formula (9) processing signal calculated from each user's subscriber signal.When this signal is counted as noise for another signal (carrying out single user over against another user when decoding), the variance of trying to achieve can be used as the power of this " noise " effectively.After the variance summation of the subscriber signal of a plurality of users except the subscriber signal of being investigated, just can regard as and be investigated the suffered total noise jamming of signal, detect thereby can carry out single user to it.

Along with the increase of iterations, before convergence, the absolute value of these priori log-likelihood ratios is with increasing, and variance is also just more and more littler so, and is close to " 0 ".So when the subscriber signal to some users detected, the noise power that becomes owing to the equivalence from other user's subscriber signal was along with iterations reduces, the precision of estimation just can improve.

According to a specific embodiment of the present invention, the signal multiplexing among the described step S12 is handled and is comprised spread spectrum and scrambling; According to a preferred embodiment of the present invention, described signal multiplexing is handled and is comprised spread spectrum, scrambling and interleaving treatment.Particularly, described signal multiplexing is handled by following process and is realized:

With the multiple receive antenna situation is example, generates new priori LLR based on merging estimated value, shown in (20) and (21).

Wherein, i=1,2 ..., frame, Represent integer arithmetic.So, not only finished spread spectrum, and removed extrinsic information, pure intrinsic information is sent in the subsequent operation.

In many yards transmission, formula (20) need be adjusted to the form of formula (22).

Then, use Come the priori log-likelihood ratio of scrambling by formula (22) gained.In fact, the purpose of the scrambling here is to exchange in DPDCH and DPCCH corresponding log-likelihood ratio, the log-likelihood ratio among each DTCH of scrambling then on the same position at random.After this, will be used for the operation (for example, from step S10 to step S12) of next iteration loop through the priori log-likelihood ratio of scrambling, until iteration convergence.According to a specific embodiment of the present invention, can preset iterations, after the number of times of iterative detection reaches predetermined value, utilize described merging estimated value (corresponding a plurality of reception antennas) or through the posteriority log-likelihood ratio (corresponding single reception antenna) of demultiplexing, carry out decision process, restore each user's signal at receiving terminal.For example, if should merge estimated value, then it is judged to 1, otherwise is judged to 0 near 1.

According to a specific embodiment of the present invention, if upward signal to be sent has been carried out interleaving treatment at transmitting terminal (being user side), then the demultiplexing among the step S11 of this method is handled and also will be comprised corresponding deinterleaving processing, and the multiplexing operation among the step S12 also will comprise corresponding interleaving treatment, be described below in conjunction with Fig. 4, Fig. 4 is the method schematic diagram that is used for signal is carried out interleaving treatment and deinterleaving processing in multi-user detection device shown in Figure 3 (or transmitter of ustomer premises access equipment) according to a specific embodiment of the present invention.

In step S11, signal is carried out process that deinterleaving handles be preferably located in after the descrambling, and be positioned at soft decoding (promptly separating spread spectrum) before.Understand easily, described deinterleaving is handled and need be based upon on the basis that base station V understands the used interleaving mode of each user of its subordinate.Correspondingly, among the described step S12, the process that signal is carried out interleaving treatment is preferably located in after the spread spectrum, and is positioned at before the scrambling.According to a specific embodiment of the present invention, base station V can by in the process of random access be connected when setting up, when being transmitted as the user and distributing scrambler, the orthogonal spectrum expansion factor (OVSF) with regard to the signal of up link, for the user distributes concrete several PT (sequence transformation label), realize further randomization, make Gaussian approximation more accurate burst.Should be appreciated that this sequence transformation label can be pre-stored in user side equally.

Please refer to Fig. 4, the left side shows the method for interleaving treatment among the figure, should be appreciated that the method for described interleaving treatment is not limited only to be applied in the multi-user detection device 1 of base station receiver equipment a, is equally applicable in user's the emitter.With the interleaving treatment in user's the emitter is example, adopts the order shown in the lower left corner that the sequence of symhols through spread spectrum is transmitted.The original transmitted of shown burst is in proper order: #1#2#...#PT-1#PT#PT+1...#frame, (precedingly address based on this sequence transformation label, base station V knows its subordinate's the used interleaving mode of each user) burst is carried out interleaving treatment as figure after, new transmission sequence is: #1#PT+1#2PT+1#...#...#frame.Right-hand part shows the method that deinterleaving is handled among the figure, is used for that burst is carried out the device that deinterleaving handles the burst that arrives is stored from top to bottom, transmits according to the order shown in the upper right corner then.Particularly, described solution sequence map function is that the burst of #1#PT+1#2PT+1#...#...#frame is stored to the transmission sequence that receives, according to the output of the order shown in the upper right corner among the figure, the transmission sequence of output sequence is: #1#2#3#4#...#...#frame, the transmission sequence of the original signal sequence of handling with non-interleaved is identical.

Scrambler reasonably will disturb (comprise noise and from other user's signal) to carry out Gaussian approximation, and this helps, and the optimum code chip level detects and multi-user's differentiation.Above-mentioned interleaving treatment then further randomization the order of each stream of chips, therefore, the suffered interference of each chip of gained has comprised the chip that obtains behind a plurality of different original information bits spread spectrums of other user from each respectively behind original information bits spread spectrum.That is to say, the interference from each original information bits of each user has been obtained further randomization.

For instance, if do not adopt sequence transformation (promptly need not distribute corresponding sequence transformation label, just do not have sequence transformation and solution sequence conversion in user and the multi-user detection device 1 yet), will include only corresponding bits to interference from other each UE from each bit of a user.Illustrate, supposing to have 8 users and spreading factor is 8, then from each one of all the other 7 users totally 7 bits constituted interference to targeted customer's corresponding bits.Adopt interleaving treatment, the interference of targeted customer's a bit is comprised that from totally 56 chips of each 8 bit of other 7 users therefore involve 56 different bits, this makes Gaussian approximation more accurate.

Adopt at user side under the situation of interleaving treatment, correspondingly, the object that despreading of carrying out at the step S11, the S12 that are used for the method for Multiuser Detection described in the described multi-user detection device 1 (soft decoding) and scrambling are handled correspondingly becomes " signal of handling through deinterleaving " and " through the signal of interleaving treatment ", repeats no more.

Followingly second aspect of the present invention is described in detail with reference to Fig. 3 and in conjunction with Fig. 1.Fig. 3 is for being used for multi-user detection device block diagram that the signal from the multi-user is detected according to a specific embodiment of the present invention in the receiving equipment a of wireless network shown in Figure 1.Described multi-user detection device 1 comprises: joint-detection device 10, Deplexing apparatus 11, signal multiplexing device 12, control device 13, judgment device 14, merging device 15.Wherein, adopt under the situation of a plurality of reception antennas at the receiving equipment a of base station V, can be each reception antenna configuration described joint-detection 10, Deplexing apparatus 11, signal multiplexing device 12 and a control device 13, and, can in a receiving equipment a, use a described merging device 15 and a judgment device 14 for considerations such as saving costs.

After comprising primary signal from each road subscriber signal of user I-IV and arriving the receiving equipment a place of base station V, described joint-detection device 10 is based on first estimated value from each user's subscriber signal is come primary signal is carried out united detection processing, to generate second estimated value from each user's subscriber signal respectively.Particularly, in the present embodiment, be modulated to example, need to calculate the probability of each reception chip of each user who forms the QPSK signal with QPSK (quaternary PSK).

Suppose to have in system K user, then the primary signal that receives of the receiving equipment a of base station V can be expressed as formula (1):

$r_i=\underset{k=1}{\overset{K}{\mathrm{\&Sigma;}}}\underset{l=1}{\overset{L_k}{\mathrm{\&Sigma;}}}{h}_k^l{x}_k^{i-\mathrm{<figure-callout\; id="1"\; label="l\; +"\; filenames="A20071003675100341.png,A20071003675100351.png"\; state="\{\{state\}\}">l</figure-callout>}+1}+n_i---\left(1\right)$

Wherein, i represents that this signal correspondence detects a plurality of i of answering in the chips of processing synchronously in the V of base station; L _kExpression is from the maximum number of the transmission path of the subscriber signal of user k; h _k ^lExpression is from the complex channel parameter of the l transmission paths of the subscriber signal of user k; n _iBe that average is 0, variance is σ ²Multiple Gaussian noise.

Rotate the QPSK symbol in mode shown in the formula (2), to obtain the planisphere of matrix pattern:

$r_i=\underset{k=1}{\overset{K}{\mathrm{\&Sigma;}}}\underset{l=1}{\overset{L_k}{\mathrm{\&Sigma;}}}{h}_k^l\frac{(1+j)(1-j)}{2}{x}_k^{i-\mathrm{<figure-callout\; id="1"\; label="l\; +"\; filenames="A20071003675100341.png,A20071003675100351.png"\; state="\{\{state\}\}">l</figure-callout>}+1}+n_i=\underset{k=1}{\overset{K}{\mathrm{\&Sigma;}}}\underset{l=1}{\overset{L_k}{\mathrm{\&Sigma;}}}\frac{h_k^l(1+j)}{\sqrt{2}}{y}_k^{i-\mathrm{<figure-callout\; id="1"\; label="l\; +"\; filenames="A20071003675100341.png,A20071003675100351.png"\; state="\{\{state\}\}">l</figure-callout>}+1}+n_i---\left(2\right)$

Y wherein _k ⁱBe a QPSK symbol, with channel parameter h with standard constellation _k ^lTurn clockwise 45 °, obtain

Its preservation is used for the processing of back.Therefore can obtain formula (3):

Wherein, η _k ^l(i) can regard a big noise that comprises from other each user's subscriber signal as.According to central-limit theorem, η _k ^l(i) can be approximately a multiple Gaussian random variable well, so its probability density function can be obtained by formula (4):

${\mathrm{pdf}}_k^{l,i}(x_1,x_2)=\frac{1}{2\mathrm{\&pi;}\sqrt{\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Re}}\right)\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Im}}\right)}}\exp [-\frac{{(x_1-E\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Re}}\right))}^2}{\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Re}}\right)}-\frac{{(x_2-E\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Im}}\right))}^2}{\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Im}}\right)}]---\left(4\right)$

Wherein, subscript " Re " and " Im " and " x ₁" and " x ₂" represent real part and imaginary part respectively.Variable η _k ^l(i) average (E) of (also being noise) and variance (var is appreciated that the power that is this noise) are provided by formula (5) and formula (6):

Wherein,

Will

With

Replace with

With Can obtain E (η _k ^l(i) ^Im), var (η _k ^l(i) ^Im, E (r _i ^Im) and var (r _i ^Im).

Multiuser Detection provided by the invention adopts the structure of Turbo type, and all users' subscriber signal is carried out joint-detection, particularly, utilizes the priori log-likelihood ratio LLR that returns from last loop feedback _PrioriPromptly With

Estimate each QPSK symbol y _k ⁱAverage and variance (owing to relate to iteration, LLR _PrioriProcurement process ask for an interview description to step S11).Particularly, this QPSK symbol y _k ⁱAverage and variance can through type (9a) and formula (9b) obtain:

$E\left\{y_k^{i^{\mathrm{Re}\left(\mathrm{Im}\right)}}\right\}=\tanh \left(\frac{{\mathrm{LLR}}_{\mathrm{priori}}\left[y_k^{i^{\mathrm{Re}\left(\mathrm{Im}\right)}}\right]}{2}\right)---\left(9a\right)$

$\mathrm{var}\left\{y_k^{i^{\mathrm{Re}\left(\mathrm{Im}\right)}}\right\}=1-E^2\left\{y_k^{i^{\mathrm{Re}\left(\mathrm{Im}\right)}}\right\}---\left(9b\right)$

According to a specific embodiment of the present invention, just having begun in Multiuser Detection is when iteration does not begin as yet for the first time, because the priori log-likelihood ratio that does not return, therefore order $E^{y_k^i}=0;$ And ${\mathrm{var}}^{y_k^i}=1.$ Promptly suppose y _k ⁱFor expectation is 0, variance is the noise of 1 (also being that power is 1), carries out the joint-detection first time.

Then, through type (10) and (11) obtain each chip-level QPSK symbol y _k ⁱ, i=1,2 ... the real part of frame (wherein, frame is a simultaneously treated multiple number of chips in multi-user detection device) and the posteriority log-likelihood ratio (LLR of imaginary part _Posterior).

Wherein subscript " 1 " is represented the 1st transmission paths.Utilize maximal index approximate, above-mentioned two formulas can be simplified to following formula (12) and formula (13).

Wherein, $f_k^{l,i}(x_1,x_2)=\frac{{(x_1-E\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Re}}\right))}^2}{\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Re}}\right)}+\frac{{(x_2-E\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Im}}\right))}^2}{\mathrm{var}\left({\mathrm{\&eta;}}_k^l{\left(i\right)}^{\mathrm{Im}}\right)}.$ Emulation shows that formula (12) and formula (13) provide cotype (10) and formula (11) capacity about the same, and therefore, this is approximate to be effective.

Calculating is before all carried out respectively at each bars transmission path, below merges the pairing posteriority log-likelihood ratio that is obtained by formula (12) and (13) of mulitpath based on RAKE receiver:

${\mathrm{LLR}}_{\mathrm{post}}^{\mathrm{RAKE}}\left[y_k^{i^{\mathrm{Re}}}\right]=\underset{l=1}{\overset{L_k}{\mathrm{\&Sigma;}}}{\mathrm{LLR}}_{\mathrm{post}}^l\left[y_k^{i^{\mathrm{Re}}}\right]$ With ${\mathrm{LLR}}_{\mathrm{post}}\left[y_k^{i^{\mathrm{Im}}}\right]=\underset{l=1}{\overset{L_k}{\mathrm{\&Sigma;}}}{\mathrm{LLR}}_{\mathrm{post}}^l\left[y_k^{i^{\mathrm{Im}}}\right]---\left(14\right)$

Use it for subsequent treatment then, represent with plural form as the formula (15):

${\mathrm{LLR}}_{\mathrm{post}}^{\mathrm{RAKE}}\left[y_k^i\right]={\mathrm{LLR}}_{\mathrm{post}}\left[y_k^{i^{\mathrm{Re}}}\right]+j{\mathrm{LLR}}_{\mathrm{post}}\left[y_k^{i^{\mathrm{Im}}}\right]---\left(15\right)$

The specific embodiment of the present invention under the non-many yards transmission has more than been described.Because many yards transmission (it is that the orthogonal spectrum expansion factor is come synchronously transmission signals that a plurality of Dedicated Physical Data Channels adopt different OVSF) are the features of UMTS, therefore, multi-user detection device provided by the invention and method thereof are also supported many yards transmission.Certainly, this method also is applicable to QAM (quadrature amplitude modulation) modulation, therefore also can be used for the HSUPA (high speed uplink packet access) in WCDMA (Wideband Code Division Multiple Access (WCDMA)) system.

Suppose that user k transmits with many coding modes, then formula (1)-(5) stand good.Because for multi-user detection device 1, the employed scrambler of each user is known, and multi-user detection device 1 is easy to just know y _k ⁱWhich part by six parallel sign indicating numbers multiplexing (be real part, or imaginary part).Therefore, by using respectively

With

Replace y _k ⁱBe re-used the part average and variance, can calculate the posteriority log-likelihood ratio, wherein subscript " u " refers to the sub-DPDCH in u rank (Dedicated Physical Data Channel), Be these u rank sub-DPDCH spreading code laminar flows, by with the similar step of formula (9), can obtain

With

Therefore, each chip among the sub-DPDCH

I=1,2 ... the posteriority log-likelihood ratio of frame (" frame " is illustrated in the number of simultaneously treated continuous plural chip among the V of base station) can be drawn by formula 16 and 17.

Wherein symbol " | Re " refers to that many yards transmission are positioned at the real part of QPSK symbol.With

With

Replace

With

Can obtain LLR _Post ^l[z _{K, u} ⁱ| Im] and

Such scheme also can utilize maximal index to be similar to simplify, and emulation shows that described maximal index is approximate can provide the performance that is close with such scheme.

Utilize RAKE receiver can obtain { LLR from merging that all transmission paths come with user k information corresponding _Post ^RAKE[z _{K, u} ⁱ| Re] } _I=1 ^FrameWith

(or { LLR _Post ^RAKE[z _{K, u} ⁱ| Im] } _I=1 ^FrameWith

), so far, generated second estimated value (in this specific embodiment, described second estimated value is the posteriority log-likelihood ratio) from each user's subscriber signal, this joint-detection device 10 passes to described Deplexing apparatus 11 with the described posteriority log-likelihood ratio of its generation:

The posteriority log-likelihood ratio from each user's subscriber signal that 11 pairs of these joint-detection devices 10 of Deplexing apparatus obtain carries out and the corresponding demultiplexing of transmitting terminal is handled, with the demultiplexing estimated value of the subscriber signal that generates described each user.According to a specific embodiment of the present invention, described demultiplexing is handled and is comprised descrambling reconciliation spread processing, and according to a preferred embodiment of the present invention, described demultiplexing processing comprises descrambling, separates spread spectrum and deinterleaving processing.Particularly, described demultiplexing is handled by following process and is realized:

If { s _k ⁱ} _I=1 ^FrameThe multiple scrambler sequence of when user side carries out scrambling to signal, using for user k.Because the QPSK signal that receives has been turned clockwise 45 ° in step S10, therefore, use The posteriority log-likelihood ratio that descrambling is obtained by joint-detection device 10;

The LLR of plural number QPSK symbols streams is mapped to two DTCH (Dedicated Traffic Channel), and being mapped among the DPDCH (Dedicated Physical Data Channel) is { LLR _Post ^RAKE[α _k ⁱ] _I=1 ^Frame, be { LLR among the DPCCH (Dedicated Physical Control Channel) and be mapped to _Post ^RAKE[b _k ⁱ] _I=1 ^FrameWherein, α _kSignal behind the corresponding transmitting terminal spread spectrum coding on DPDCH; And b _kThe signal on DPCCH behind the then corresponding transmitting terminal spread spectrum coding.

Persons of ordinary skill in the art may appreciate that in many yards transmission { LLR _Post ^RAKE[z _{K, u} ⁱ] _I=1 ^FrameBe mapped to u rank DPDCH.

Then, described burst through descrambling being carried out soft decoding (Soft Decoding) also is that despreading is handled.Shown in following formula (18) and formula (19):

${\mathrm{LLR}}^{\mathrm{ant}}\left[{\mathrm{\&alpha;}}_k^i\right]=\underset{p=(i-1)M_{\mathrm{\&alpha;}}+1}{\overset{{\mathrm{iM}}_{\mathrm{\&alpha;}}}{\mathrm{\&Sigma;}}}{\mathrm{\&omega;}}_k^{p-(i-1)\&times;M_{\mathrm{\&alpha;}}}\&times;{\mathrm{LLR}}_{\mathrm{post}}^{\mathrm{RAKE}}{\left[a_k^p\right]}_{\mathrm{ant}},i=\mathrm{1,2},\&CenterDot;\&CenterDot;\&CenterDot;,\frac{\mathrm{frame}}{M_{\mathrm{\&alpha;}}}---\left(18\right)$

${\mathrm{LLR}}^{\mathrm{ant}}\left[{\mathrm{\&beta;}}_k^i\right]=\underset{p=(i-1)M_{\mathrm{\&beta;}}+1}{\overset{{\mathrm{iM}}_{\mathrm{\&beta;}}}{\mathrm{\&Sigma;}}}{\mathrm{\&upsi;}}_k^{p-(i-1)\&times;M_{\mathrm{\&beta;}}}\&times;{\mathrm{LLR}}_{\mathrm{post}}^{\mathrm{RAKE}}{\left[b_k^p\right]}_{\mathrm{ant}},i=\mathrm{1,2},\&CenterDot;\&CenterDot;\&CenterDot;,\frac{\mathrm{frame}}{M_{\mathrm{\&beta;}}}---\left(19\right)$

ant＝1，2，...ANT

Wherein, " α _k" signal before the spread spectrum coding of corresponding transmitting terminal on DPDCH, and " β _k" the preceding signal on DPCCH of corresponding transmitting terminal spread spectrum coding; M is the spreading factor on the respective channel; " ant " and " ANT " represents certain reception antenna in the multi-antenna structure and the sum of reception antenna respectively, subscript " ^l" refer to the 1st reception antenna.Understand easily, in many yards transmission, use M _γAnd z _{K, u} ^pReplace respectively

M _αAnd a _k ^pAfter, can obtain LLR ^Ant[γ _{K, u} ⁱ], wherein, γ ⁱ _{K, μ}Signal on corresponding transmitting terminal each DPDCH before spread spectrum coding, and ω _kBe channel code, so far, Deplexing apparatus 11 has been finished the demultiplexing of signal has been handled, and has generated the demultiplexing estimated value of described each user's subscriber signal;

If described receiving equipment a only comprises a reception antenna, then can directly the demultiplexing estimated value be passed to described signal multiplexing device 12; If described receiving equipment a comprises a plurality of reception antennas, then also need utilize one to merge device 15 the demultiplexing estimated value of pairing each user's of a plurality of reception antennas same signal (the posteriority log-likelihood ratios of handling through Deplexing apparatus 11) is merged, with the merging estimated value of the subscriber signal that generates each user.Particularly, utilize following formula to making up at the posteriority log-likelihood ratio of handling through this Deplexing apparatus 11:

LLR[u]＝∑ _{1≤ant≤ANT}LLR ^ant[u]

Wherein variable u represents α in non-many yards transmission _k ⁱAnd β _k ⁱ, in many yards transmission, represent γ _{K, u} ⁱAnd β _k ⁱBy collecting the information of coming, and it is made up estimate some bits, observe more confirmation, only need iteration loop seldom just can estimate to restrain a stage from a plurality of reception antennas.After merging, will merge estimated value and pass to signal multiplexing device 12;

12 pairs of described demultiplexing estimated values of signal multiplexing device (corresponding single reception antenna) or merging estimated value (corresponding multiple receive antenna) are carried out signal multiplexing and are handled, to generate new priori log-likelihood ratio, be used for power and variance in as the formula (9) processing signal calculated from each user's subscriber signal.When this signal is counted as noise for another signal (carrying out single user over against another user when decoding), the variance of trying to achieve can be used as the power of this " noise " effectively.After the variance summation of the subscriber signal of a plurality of users except the subscriber signal of being investigated, just can regard as and be investigated the suffered total noise jamming of signal, detect thereby can carry out single user to it.

Along with the increase of iterations, before convergence, the absolute value of these priori log-likelihood ratios is with increasing, and variance is also just more and more littler so, and is close to " 0 ".So when the subscriber signal to some users detected, the noise power that becomes owing to the equivalence from other user's subscriber signal was along with iterations reduces, the precision of estimation just can improve.

According to a specific embodiment of the present invention, the signal multiplexing that described signal multiplexing device 12 carries out is handled and is comprised spread spectrum and scrambling; According to a preferred embodiment of the present invention, described signal multiplexing is handled and is comprised spread spectrum, scrambling and interleaving treatment.Particularly, described signal multiplexing is handled by following process and is realized:

With the multiple receive antenna situation is example, generates new priori LLR based on merging estimated value, shown in (20) and (21).

Wherein, i=1,2 ..., frame,

Represent integer arithmetic.So, not only finished spread spectrum, and removed extrinsic information, pure intrinsic information is sent in the subsequent operation.

In many yards transmission, formula (20) need be adjusted to the form of formula (22).

Then, use Come the priori log-likelihood ratio of scrambling by formula (22) gained.In fact, the purpose of the scrambling here is to exchange in DPDCH and DPCCH corresponding log-likelihood ratio, the log-likelihood ratio among each DTCH of scrambling then on the same position at random.

After this described control device 13 will be used for the operation of next iteration loop through the priori log-likelihood ratio of scrambling, and for example, control joint-detection device 10, Deplexing apparatus 11 and signal multiplexing device 12 repeat operation separately, until iteration convergence.According to a specific embodiment of the present invention, can preset iterations, after the number of times of iterative detection reaches predetermined value, utilize described merging estimated value (corresponding a plurality of reception antennas) or through the posteriority log-likelihood ratio (corresponding single reception antenna) of demultiplexing by described judgment device 14, carry out decision process, restore each user's signal at receiving terminal.For example, if should merge estimated value, then it is judged to 1, otherwise is judged to 0 near 1.

According to a specific embodiment of the present invention, if upward signal to be sent has been carried out interleaving treatment at transmitting terminal (being user side), then this Deplexing apparatus 11 should comprise the device (not illustrating in the drawings for simplicity) that is used for signal is carried out the deinterleaving processing, and the multiplexing operation of described signal multiplexing device 12 also will comprise the device (not illustrating in the drawings for simplicity) that is used for signal is carried out interleaving treatment accordingly, be described below in conjunction with Fig. 4.

Preferably, describedly be used for that signal is carried out the device that deinterleaving handles the signal through descrambling is handled, handle and will be used for follow-up soft decoding (promptly separating spread spectrum) through the signal that its deinterleaving is handled.Understand easily, described deinterleaving is handled and need be based upon on the basis that base station V understands the used interleaving mode of each user of its subordinate.Correspondingly, the described device that is used for signal is carried out interleaving treatment is handled the signal through spread spectrum, handles and will be used for follow-up scrambling through the signal of its interleaving treatment.According to a specific embodiment of the present invention, base station V can by in the process of random access be connected when setting up, when being transmitted as the user and distributing scrambler, the orthogonal spectrum expansion factor (OVSF) with regard to the signal of up link, for the user distributes concrete several PT (sequence transformation label), realize further randomization, make Gaussian approximation more accurate burst.Should be appreciated that this sequence transformation label can be pre-stored in user side equally.

Please refer to Fig. 4, the left side shows the method for interleaving treatment among the figure, should be appreciated that the method for described interleaving treatment is not limited only to be applied in the multi-user detection device 1 of base station receiver equipment a, is equally applicable in user's the emitter.With the interleaving treatment in user's the emitter is example, adopts the order shown in the lower left corner that the sequence of symhols through spread spectrum is transmitted.The original transmitted of shown burst is in proper order: #1#2#...#PT-1#PT#PT+1...#frame, (precedingly address based on this sequence transformation label, base station V knows its subordinate's the used interleaving mode of each user) burst is carried out interleaving treatment as figure after, new transmission sequence is: #1#PT+1#2PT+1#...#...#frame.Right-hand part shows the method that deinterleaving is handled among the figure, is used for that burst is carried out the device that deinterleaving handles the burst that arrives is stored from top to bottom, transmits according to the order shown in the upper right corner then.Particularly, described solution sequence map function is that the burst of #1#PT+1#2PT+1#...#...#frame is stored to the transmission sequence that receives, according to the output of the order shown in the upper right corner among the figure, the transmission sequence of output sequence is: #1#2#3#4#...#...#frame, the transmission sequence of the original signal sequence of handling with non-interleaved is identical.Wherein, the set of chip under the sequence transformation tag length after will interweaving is called a Page (page or leaf), and the size of this Page also correspondence the size of a subdivision of transmitter register and receiving register.

Scrambler reasonably will disturb (comprise noise and from other user's signal) to carry out Gaussian approximation, and this helps, and the optimum code chip level detects and multi-user's differentiation.Above-mentioned interleaving treatment then further randomization the order of each stream of chips, therefore, the suffered interference of each chip of gained has comprised the chip that obtains behind a plurality of different original information bits spread spectrums of other user from each respectively behind original information bits spread spectrum.That is to say, the interference from each original information bits of each user has been obtained further randomization.

For instance, if do not adopt sequence transformation (promptly need not distribute corresponding sequence transformation label, just do not have sequence transformation and solution sequence conversion in user and the multi-user detection device 1 yet), will include only corresponding bits to interference from other each UE from each bit of a user.Illustrate, supposing to have 8 users and spreading factor is 8, then from each one of all the other 7 users totally 7 bits constituted interference to targeted customer's corresponding bits.Adopt interleaving treatment, the interference of targeted customer's a bit is comprised that from totally 56 chips of each 8 bit of other 7 users therefore involve 56 different bits, this makes Gaussian approximation more accurate.

Adopt at user side under the situation of interleaving treatment, correspondingly, the object that despreading of carrying out in the Deplexing apparatus 11 of described multi-user detection device 1 and signal multiplexing device 12 (soft decoding) and scrambling are handled correspondingly becomes " signal of handling through deinterleaving " and " through the signal of interleaving treatment ", repeats no more.

Transmitting terminal (ustomer premises access equipment)

For improving the precision of Gaussian approximation, the present invention preferably carries out interleaving treatment to burst in the transmitter b of user side, further the randomization chip sequence.Below specifically be described in conjunction with Fig. 5 and Fig. 6 and with reference to Fig. 1.

Fig. 5 is for being used for the method flow diagram that auxiliary reception equipment a (being positioned at V place, base station) carries out Multiuser Detection according to a specific embodiment of the present invention in the transmitter b of wireless network shown in Figure 1.As seen from the figure, the transmitter b of ustomer premises access equipment utilizes the PT (sequence transformation label) that prestores that the signal (chip sequence) through spread processing is carried out interleaving treatment, chip sequence on each channel after the interleaving treatment is through merging (for simplicity's sake, the step of chip sequence on described each channel of not shown merging), the signal that obtains being shown below $c_k^{\frac{2560}{\mathrm{PT}}\&times;(\mathrm{\&zeta;}-1)+\mathrm{\&xi;}}=a_k^{\mathrm{PT}\&times;(\mathrm{\&xi;}-1)+\mathrm{\&zeta;}}+j\&times;b_k^{\mathrm{PT}\&times;(\mathrm{\&xi;}-1)+\mathrm{\&zeta;}},\mathrm{\&zeta;}=\mathrm{1,2},\&CenterDot;\&CenterDot;\&CenterDot;,\mathrm{PT},\mathrm{\&xi;}=\mathrm{1,2},\&CenterDot;\&CenterDot;\&CenterDot;,\frac{2560}{\mathrm{PT}},$ With multiple scrambler it being carried out scrambling again handles.Multiple scrambler stream { s _k ⁱ} _I=1 ^FrameWith speed among the UMTS is that the scrambler stream of 3.84Mps is identical. ${\left\{x_k^i\right\}}_{i=1}^{\mathrm{frame}}={\left\{p_k^i\right\}}_{i=1}^{\mathrm{frame}}+j\&times;{\left\{q_k^i\right\}}_{i=1}^{\mathrm{frame}}$ The chip sequence that expression sends can adopt QPSK or QAM modulation, wherein { p _k ⁱ} _J=1 ^Frame{ q _k ⁱ} _J=1 ^FrameIt is sequence of real numbers.Among the figure, M _α, M _βBe the spreading factor on the respective channel;

The expression spreading code; Frame is illustrated in simultaneously treated number of chips among the transmitter b, understands easily, and corresponding original information bits number is frame/M _{α (β)}

Be to be understood that, though below only the described method under the non-many yards transmission meanss is described, but those skilled in the art can understand, under many yards transmission meanss, as long as according to foregoing description, carry out interleaving treatment respectively and get final product on each DPDCH, the chip sequence after being combined again carries out scrambling with multiple scrambler to be handled.

Fig. 6 is for being used for the device block diagram that auxiliary reception equipment a (being positioned at V place, base station) carries out Multiuser Detection according to a specific embodiment of the present invention in the transmitter b of wireless network shown in Figure 1.In order to show processing procedure according to present embodiment, be used to utilize the sequence transformation label that prestores that burst to be sent is carried out the servicing unit 21 of interleaving treatment except illustrating among Fig. 6, also show spread spectrum device 20 and scrambling apparatus 22.Particularly, this servicing unit 21 utilizes the PT (sequence transformation label) that prestores that the signal (chip sequence) that is carried out spread processing by spread spectrum device 20 and obtain is carried out interleaving treatment, then through merging (for simplicity's sake through the chip sequence on each channel of interleaving treatment, the not shown device that is used to merge chip sequence on described each channel), obtain as shown in the formula $c_k^{\frac{2560}{\mathrm{PT}}\&times;(\mathrm{\&zeta;}-1)+\mathrm{\&xi;}}=a_k^{\mathrm{PT}\&times;(\mathrm{\&xi;}-1)+\mathrm{\&zeta;}}+j\&times;b_k^{\mathrm{PT}\&times;(\mathrm{\&xi;}-1)+\mathrm{\&zeta;}},\mathrm{\&zeta;}=\mathrm{1,2},\&CenterDot;\&CenterDot;\&CenterDot;,\mathrm{PT},\mathrm{\&xi;}=\mathrm{1,2},\&CenterDot;\&CenterDot;\&CenterDot;,\frac{2560}{\mathrm{PT}}$ Shown signal, this signal utilize multiple scrambler to carry out scrambling by scrambling apparatus 22 again and handle.Be to be understood that, though below only to the described transmitter b under the non-many yards transmission meanss particularly wherein servicing unit 21 be described, but those skilled in the art can understand, under many yards transmission meanss, as long as according to foregoing description, carry out interleaving treatment respectively and get final product on each DPDCH, the chip sequence after being combined again carries out scrambling with multiple scrambler to be handled.

Below in conjunction with analogous diagram advantage of the present invention is described.

Ask for an interview Fig. 7, as seen, in present UMTS system, do not use such MUD, and directly come separate users with scrambler, the performance distance ideal effect greatly differs from each other.

In emulation, suppose that channel is an additive white Gaussian noise channel, adopt the DPDCH of 240kbps, since the capacity of DPCCH is not a problem, just do not consider DPCCH.When PT=1, utilize this programme can strengthen UMTS.MUD in this programme (multi-user detector) handles a time slot at every turn, and this time slot comprises 2560 chips of 160 bits, wherein, does not adopt chnnel coding.Simulation result before Fig. 7 provides time slot to cut apart.

In Fig. 7, " max " and " exp " represents approximate MUD and original MUD respectively.K is the total number of UE in the system (subscriber equipment).KUMTS represents to have existing coding/decoding method among the UMTS of K UE.For " 12max (exp) " and " 16max (exp) " predefine one 8 loop iteration, still less adopting 6 loop iteration in the user.MUD in this programme provides than existing UMTS more performance obviously, and can access more performance by chnnel coding.

Original MUD among UMTS when Fig. 8 has shown PT=1 and approximate MUD restrain in a spot of loop, and for example for the system with 12 UE, 5 to 6 loops are enough.Fig. 7 and 8 has proved the approximate validity of max log.

Fig. 9 has shown that the hypothesis spreading factor is 8 480kbps, the performance of the approximate MUD of the maximum of DPDCH, and transmission channel is an additive white Gaussian noise channel, and the PT vector is [16,8,32,5,64,10,20,40,2,4], and wherein each clauses and subclauses is distributed to different UE.During by PT=1, MUD is compared, be very easy to find and carry out the MUD of sequence transformation bigger capacity is provided sending sequence.

More than specific embodiments of the invention are described.It will be appreciated that the present invention is not limited to above-mentioned specific implementations, those skilled in the art can make various distortion or modification within the scope of the appended claims.

Claims (18)

1. one kind is used for method that the signal from the multi-user is detected in the receiving equipment of wireless network, may further comprise the steps:

A. come primary signal is carried out united detection processing based on first estimated value from each user's subscriber signal, to generate second estimated value from each user's subscriber signal respectively, wherein said primary signal comprises the subscriber signal from all users;

B. respectively second estimated value of described subscriber signal from each user is carried out demultiplexing and handle, with the demultiplexing estimated value of the subscriber signal that generates described each user;

C. respectively the demultiplexing estimated value of described each user's subscriber signal is carried out signal multiplexing and handle, to generate the first new estimated value from each user's subscriber signal;

D. the first new estimated value with described subscriber signal repeats above-mentioned steps a-c until satisfying predetermined condition as first estimated value.

2. method according to claim 1 is characterized in that, and is further comprising the steps of:

F. after satisfying predetermined condition, the demultiplexing estimated value of described each user's subscriber signal is carried out decision process, to generate described each user's output signal.

3. method according to claim 1 is characterized in that, and is further comprising the steps of:

B '. the demultiplexing estimated value of pairing each user's of a plurality of reception antennas same signal is merged, with the merging estimated value of the subscriber signal that generates each user;

Wherein, described step c is: respectively the estimated value through merging of described each user's subscriber signal is carried out signal multiplexing and handle, to generate the first new estimated value from each user's subscriber signal.

4. method according to claim 3 is characterized in that, and is further comprising the steps of:

F. after satisfying predetermined condition, the merging estimated value of described each user's subscriber signal is carried out decision process, to generate described each user's output signal.

5. according to each described method among the claim 1-4, it is characterized in that described step a also comprises:

To each user, based on first estimated value from other all users' subscriber signal is come primary signal is carried out united detection processing, to generate second estimated value respectively from this user's subscriber signal.

6. according to each described method among the claim 1-5, it is characterized in that described step b also comprises:

Respectively second estimated value of described subscriber signal from each user is carried out descrambling and/or despreading and/or deinterleaving and handle, the subscriber signal of handling with the descrambling that generates described each user and/or despreading and/or deinterleaving;

Wherein, described step c also comprises:

The subscriber signal through reduction to described each user carries out scrambling and/or spread spectrum and/or interleaving treatment respectively, to generate the first new estimated value from each user's subscriber signal.

7. according to each described method among the claim 1-6, it is characterized in that described first estimated value is the priori log-likelihood ratio; Described second estimated value is the posteriority log-likelihood ratio.

8. one kind is used for multi-user detection device that the signal from the multi-user is detected in the receiving equipment of wireless network, comprising:

The joint-detection device, be used for based on first estimated value from each user's subscriber signal is come primary signal is carried out united detection processing, to generate second estimated value from each user's subscriber signal respectively, wherein said primary signal comprises the subscriber signal from all users;

Deplexing apparatus is used for that respectively second estimated value of described subscriber signal from each user is carried out demultiplexing and handles, with the demultiplexing estimated value of the subscriber signal that generates described each user;

The signal multiplexing device is used for that respectively the demultiplexing estimated value of described each user's subscriber signal is carried out signal multiplexing and handles, to generate the first new estimated value from each user's subscriber signal;

Control device is used to control described joint-detection device, Deplexing apparatus and signal multiplexing device the first new estimated value of described subscriber signal is repeated above-mentioned processing until satisfying predetermined condition as first estimated value.

9. multi-user detection device according to claim 8 is characterized in that, also comprises:

Judgment device is used for after satisfying predetermined condition, the demultiplexing estimated value of described each user's subscriber signal is carried out decision process, to generate described each user's output signal.

10. multi-user detection device according to claim 8 is characterized in that, also comprises:

Merge device, the demultiplexing estimated value of pairing each user's of a plurality of reception antennas same signal is merged, with the merging estimated value of the subscriber signal that generates each user;

Wherein, described signal multiplexing device also is used for, and respectively the estimated value through merging of described each user's subscriber signal is carried out signal multiplexing and handles, to generate the first new estimated value from each user's subscriber signal.

11. multi-user detection device according to claim 10, it is characterized in that described judgment device also is used for, after satisfying predetermined condition, the merging estimated value of described each user's subscriber signal is carried out decision process, to generate described each user's output signal.

12. each described multi-user detection device according to Claim 8-11, it is characterized in that, described joint-detection device also is used for, to each user, based on first estimated value from other all users' subscriber signal is come primary signal is carried out united detection processing, to generate second estimated value respectively from this user's subscriber signal.

13. each described multi-user detection device is characterized in that according to Claim 8-12, described Deplexing apparatus comprises:

Descrambler and/or despreading device and/or de-interleaving apparatus, be used for that respectively second estimated value of described subscriber signal from each user is carried out descrambling and/or despreading and/or deinterleaving and handle, the subscriber signal of handling with the descrambling that generates described each user and/or despreading and/or deinterleaving;

Wherein, described signal multiplexing device also comprises:

Scrambling and/or spread spectrum and/or interlaced device are used for respectively described each user's the subscriber signal through reduction is carried out scrambling and/or spread spectrum and/or interleaving treatment, to generate the first new estimated value from each user's subscriber signal.

14. each described multi-user detection device is characterized in that according to Claim 8-13, described first estimated value is the priori log-likelihood ratio; Described second estimated value is the posteriority log-likelihood ratio.

15. the receiving equipment in wireless network is characterized in that, comprises according to Claim 8 in-14 each described multi-user detection device that the signal from the multi-user is detected of being used for.

16. one kind is used for the method that auxiliary reception equipment carries out Multiuser Detection in the transmitter of wireless network, it is characterized in that, utilizes the relevant information that interweaves that prestores to carry out interleaving treatment to sent burst.

17. one kind is used for the servicing unit that auxiliary reception equipment carries out Multiuser Detection in the transmitter of wireless network, it is characterized in that, utilizes the relevant information that interweaves that prestores to carry out interleaving treatment to sent burst.

18. the transmitter in wireless network is characterized in that, comprises the servicing unit that auxiliary reception equipment carries out Multiuser Detection that is used for according to claim 17.

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