CN1384679A - Interference-eliminating baseband processing method based on intelligent antenna - Google Patents

Abstract

The interference-eliminating baseband processing method based on intelligent antenna includes: channel estimation, searching the strongest path in multiple-path signal, obtaining the strong-path signal level signal, merging treatment of multiple paths, re-constituting strong-path code sheet level signal, elimianting the interference of the strong-path signal to the multiple-path signals in the received signals, and repeating the above said steps. The present invention can reduce multple-address interference between subscribers and raise system performance.

Description

Interference-eliminating baseband processing method based on smart antenna

The present invention relates to the signal processing method of wireless communication field, relate in particular to the baseband processing method of the interference eliminated of smart antenna.

,, improve system sensitivity and under low transmitting power, obtain communication distance far away particularly in code division multiple access (CDMA) wireless communication system in modern wireless communication systems, all adopt so-called intelligent antenna technology in order to improve power system capacity.Its relevant base station, comprise aerial array, corresponding feeder cable and one group of relevant radio-frequency (RF) transceiver that one or more antennas are formed, according to the received differential responses of each antenna element in the aerial array from the signal of user terminal, obtain the space characteristics vector and the direction of arrival of signal of this signal by baseband processor, realize the antenna beam figuration by corresponding algorithm again.

Because radio communication, especially mobile communication, be therefore must considering of in mobile environment complicated and changeable, working serious the time become and multipath transmisstion influences.For eliminate above one to, at present a lot of scholars just are being devoted to the research of the beamforming algorithm of smart antenna, its algorithm is comparatively complicated.But under mobile communication environment, wave beam forming must be finished in real time, and present digital signal processor can't be finished the real-time processing of this complexity, the interference cancellation method that must find a kind of simple, real-time working and be convenient to use in wireless system.

Patent application CN99111349.7 has proposed a kind of baseband processing method of the interference eliminated based on smart antenna.In this method, at first carry out channel estimating; Next utilizes the result of channel estimating to carry out the search in strong footpath, and to strong footpath signal carry out that intelligent antenna beam shaping is handled and the despreading scramble process to extract useful symbol level signal; Secondly the useful symbol level signal that obtains is carried out the data reconstruction of strong footpath signal again, and add that scrambler is to obtain the reconstruction signal of strong footpath chip-level; Then from received signal, deduct this reconstruction signal, promptly eliminated of the interference of strong footpath signal weak footpath signal; Constantly repeat above-mentioned steps then, eliminating strong footpath one by one according to the height order of multipath energy disturbs so that recover each footpath signal exactly, if the signal to noise ratio of a certain user's multipath useful signal has reached predetermined thresholding, then can no longer handle this user, directly utilize restoring signal to carry out the symbol judgement line output of going forward side by side, specify requirement to export the result of subscriber signal otherwise must wait until that the elimination number of times that multipath is disturbed has reached.In this method, mainly considered the interference eliminated of strong footpath signal, but do not considered the phase mutual interference between the strong footpath of different user, so its accuracy of eliminating interference, restoring signal is not high weak footpath signal.

The objective of the invention is for a kind of interference-eliminating baseband processing method based on smart antenna is provided, it can consider the phase mutual interference between the strong footpath of different user, improve the accuracy that signal recovers, the multiple access that can reduce multipath transmission interference and other subscriber signal simultaneously disturbs.

For achieving the above object, solution of the present invention is: at the baseband signal that each array element of antenna receives, the present invention will eliminate processing to the phase mutual interference between the strong footpath of each user earlier before eliminating the interference of strong footpath.Its concrete steps are:

A, baseband receiving signals is carried out channel estimating, obtain the channel estimating of each subscriber channel on each array element;

B, utilize channel estimating to search out most powerful path in the untreated multipath signal;

C, utilize the strong footpath information search, obtain each user's strong footpath symbol level signal;

D, each user's of reconstruct strong footpath chip level signal utilizes all users' reconstruction signal to eliminate the strong directly interference of signal of other user in each user's received signal, extracts the symbol level signal in the strong footpath of each user then again;

E, the merging that each user is carried out multipath are respectively handled;

The chip level signal in F, each user's of reconstruct strong footpath, the strong footpath of whole users signal is to the interference of untreated multipath signal in the elimination received signal;

G, execution in step B to F repeatedly.

Utilize channel estimation value to carry out power among the aforesaid step B earlier and estimate,, find out the most powerful path of untreated multipath signal again according to the distribute power situation of estimating.

Described step C and D utilize strong footpath information that back searches and each user's spreading code to carry out despreading descrambling and smart antenna algorithm process to received signal, obtain each user's strong footpath symbol level signal.

Eliminate the purpose of disturbing in order further to reach to finish expeditiously, can also add the processing of a judgement in the back of aforesaid step F or G: a) user's signal interference ratio meets the demands; B) multipath number of having handled has surpassed the length of channel estimating impulse response or the number of appointment.As long as judged result satisfies in above-mentioned two conditions any one, then recover all subscriber signal results; Otherwise, will continue execution in step G.Can before carrying out, aforesaid step B judge earlier also whether the multipath number of having handled surpasses the length of channel estimating impulse response or the number of appointment, then recovers all subscriber signal results in this way, otherwise continues execution in step B.

The present invention is by the chip level signal in the strong footpath of each user of reconstruct, utilize all users' reconstruction signal to eliminate the strong directly interference of signal of other user in each user's received signal, before disturbing weak footpath signal, the strong footpath of elimination carried out eliminating the different user phase mutual interference between the footpath by force, overcome conventional method and can only eliminate strong footpath to the interference of weak footpath signal and to the helpless shortcoming of the interference between the strong footpath, thereby make this method to disturb by anti-multipath, and the multiple access that can reduce between the user disturbs the raising systematic function.

System is an example with TD SDMA (TD-SCDMA), below in conjunction with the drawings and specific embodiments the utility model is described in further detail.

Fig. 1 is the intelligent antenna base station structured flowchart that the present invention has anti-interference function.

Fig. 2 is the first kind of flow chart that the present invention is based on the baseband processing method of smart antenna and interference eliminated.

Fig. 3 is the second kind of flow chart that the present invention is based on the baseband processing method of smart antenna and interference eliminated.

Fig. 4 is the third flow chart that the present invention is based on the baseband processing method of smart antenna and interference eliminated.

Fig. 5 is the first kind of flow process detail drawing that the present invention is based on the baseband processing method of smart antenna and interference eliminated.

Fig. 1 has provided the intelligent antenna base station structured flowchart that the present invention has anti-interference function.It mainly comprises j same antenna element 1, the feeder cable 2 that the j bar is same, j radio-frequency (RF) transceiver 3 and the baseband processor of being made up of channel estimation module 4 and smart antenna Interference Cancellation module 5.For the present invention, mainly be that baseband processor is carried out.All radio-frequency (RF) transceiver 3 are used same local oscillation signal source, work mutually to guarantee each radio-frequency (RF) transceiver in the base station.

Supposing has K user in the TD-SCDMA wireless communication system, the array element number of antenna array is J, and the baseband signal that antenna array receives is r ₁(n), j=1 ... J describes in detail shown in the figure, to baseband receiving signals r based on first kind of flow process of the baseband processing method of smart antenna and interference eliminated based on first kind of flow chart, Fig. 5 of the baseband processing method of smart antenna and interference eliminated as Fig. 2 _j(n) processing procedure is as follows:

(1) channel estimating: baseband receiving signals r _j(n) enter channel estimation module 4, its concrete processing procedure is:

Suppose that k subscriber channel based on the recovering pulse response of array element j is: H ^j _k=[h ^j _{K, 1}, h ^j _{K, 2}H ^j _{K, W}] ^T, to be W be written as vector form with K user based on the channel response of array element j to its channel impulse response length: H ^j=[(H ^j ₁) ^T, (H ^j ₂) ^T(H ^j _K) ^T] ^T

The middle pilot code (midamble sign indicating number) of supposing k user is m ^(k), the length of middle pilot code be L then k user's middle pilot code can be expressed as $m^{\left(k\right)}={[m_1^{\left(k\right)},m_2^{\left(k\right)}...m_L^{\left(k\right)}]}^T$ ,, therefore, receive initial W-1 the element of pilot tone (midamble) in the middle of each yard and be not used in channel estimating because the length of supposition channel impulse response is the influence that initial W-1 sampled data in the W received signal is subjected to the time delayed signal of other sequence.By the well-determined received signal of middle pilot code itself L-W+1 element only arranged, the received signal of establishing corresponding j array element is E _j=[e _{J, 1}, e _{J, 2}... e _{J, L-W+1}] ^TCan carry out following channel estimating according to this L-W+1 element: ${\hat{H}}^j={\left(G^{*T}G\right)}^{-1}{G}^{*T}{E}_j$ , wherein

Be the channel impulse response H of array element j ^jEstimation, G is the user ID matrix, is a matrix of being determined by pilot code in the middle of the user, wherein, G=[G ⁽¹⁾, G ⁽²⁾G ^(K)], $G^{\left(k\right)}=\left(G_{\mathrm{ij}}^{\left(k\right)}\right),k=1...K,G_{\mathrm{ij}}^{\left(k\right)}=m_{W+i-j}^{\left(k\right)},$ I=1 ... L-W+1; J=1 ... W, promptly $G^{\left(k\right)}=\left[\begin{array}{cccc}{m}_W^{\left(k\right)}& m_{W-1}^{\left(k\right)}& ...& m_1^{\left(k\right)}\\ m_{W+1}^{\left(k\right)}& m_W^{\left(k\right)}& ..& m_2^{\left(k\right)}\\ ...& ...& ...& ...\\ m_L^{\left(k\right)}& m_{L-1}^{\left(k\right)}& ...& m_{L-W+1}^{\left(k\right)}\end{array}\right].$

(2) power is estimated: utilize channel estimation value to carry out power and estimate, estimate the distribute power situation of each footpath signal in each subscriber channel, the power in k user's l footpath is estimated as ${\hat{P}}_{k,l}=\underset{j=1}{\overset{J}{\mathrm{\Σ}}}\mathrm{abs}\left(h_{k,l}^{\hat{j}}\right)$ , wherein Be the channel estimation value of the l footpath of k subscriber channel based on array element j.Because the corresponding relation of power and energy, a prominent footpath are promptly for the strongest footpath of energy.

This step is finished by a power estimation module, calculates all users' main footpath and the distribute power situation of multipath in search window.

(3) the strong footpath of search: according to the distribute power situation of estimating , find out the most powerful path in the untreated multipath signal of each user.Specific implementation can be to carry out signal in the distribute power situation feed signals maker that previous step is calculated suddenly to generate, and calculates the loca of each user's maximum peak power, and peak point is stored in the power points.Described when calculating each user's peak-peak loca, for most powerful path not with other user on same point with user base station asynchronous, send the adjustment parameter to its sending module.

(4) recover strong footpath symbol level signal: the spreading code that utilizes strong footpath information that back searches and each user is r to received signal ^j(n) carry out despreading descrambling and smart antenna algorithm process, obtain each user's strong footpath symbol level signal S ^{K, p}(d), suppose that wherein the strong footpath that back searches user k is the p footpath.

The above-mentioned smart antenna algorithm implementation method of mentioning can adopt the method for wave beam forming, other method is also arranged certainly, as long as this method can extract strong footpath symbol level signal from the waveform of despreading.The implementation method of wave beam forming has a lot, and wherein the ceiling capacity merge algorithm is the easiest the simplest realization.The specific implementation that adopts ceiling capacity to merge can be expressed as: $S_{k,p}\left(d\right)=\frac{1}{Q}\underset{j=1}{\overset{J}{\mathrm{\Σ}}}\underset{q=1}{\overset{Q}{\mathrm{\Σ}}}{\left(h_{k,p}^j\right)}^{*}\·r_j((d-1)Q+q+p_k)C_k^{*}\left(q\right)C_s^{*}\left(q\right)$ , wherein, S _{K, p}(d) be the symbol level restoring signal in d symbol p footpath of k user,

Be the channel estimation value of k user p footpath based on array element j, Q represents spreading factor, p _kRepresent the delay number of chips of k user p footpath, C with respect to first footpath _k(q) k user's of expression spreading code, C _s(q) scrambler of expression sub-district employing, subscript * represents this numerical value is asked conjugation.

(5) the strong footpath of reconstruct chip level signal is eliminated the interference between the strong footpath of different user, extracts strong footpath symbol level signal again: utilize S _{K, p}(d), each user of scrambler reconstruct of the channel estimation value in this footpath, each user's spreading code and sub-district is based on the chip level signal in the strong footpath of each array element , utilize all users' reconstruction signal that each user is handled respectively simultaneously, eliminate received signal r _j(n) interference of the strong footpath of other user signal in, , utilize the reception data of eliminating after disturbing then

Carry out despreading descrambling and beam forming processing once more, extract the symbol level signal S in the strong footpath of each user again _{K, p}(d).In this step, restructuring procedure can be declared the result and realizes based on soft, also can realize that wherein a kind of reconstruct mode is based on declaring the result firmly: $S_{k,p}^j(Q(d-1)+q+p_k)=h_{k,p}^j{S}_{k,p}\left(d\right)C_k\left(q\right)C_s\left(q\right)/\underset{j=1}{\overset{J}{\mathrm{\Σ}}}|h_{k,p}^j{|}^2,q=1...Q,$ Wherein

The reconstruct chip level signal of representing k user p footpath.In this step, interference eliminated can adopt following method: Also can adopt the removing method of fixing power or self adaptation power.

Because the interference between the user mainly concentrates on each with in the interference between the householder footpath, therefore can be only main footpath signal be carried out interference eliminated between this user.

(6) time domain multipath RAKE merges: the merging of each user being carried out multipath is respectively handled, and the multipath signal of soon having handled acquisition carries out time domain RAKE and merges, and the result after will merging is kept at variable S _k(d), i.e. S _k(d)=S _k(d)+S _{K, p}(d), wherein, S _k(d) the symbol level restoring signal of d symbol of k user of expression, S _k(d) initial value is made as zero.

(7) handling end condition judges: this step will be carried out two judgements, and one is that the signal interference ratio that utilizes restored symbol level signal to carry out the user is judged, one is that the multipath number of utilizing handled this moment is judged.Two can termination condition have: a) user's signal interference ratio meets the demands; B) multipath number of having handled has surpassed the length of channel estimating impulse response or the number of appointment.As long as judged result satisfies in above-mentioned two conditions any one, then can directly utilize this subscriber signal S _k(d) carry out symbol judgement and export court verdict; Otherwise, will continue following steps subscriber signal will be handled.

The signal interference ratio of described estimating user comprises: the power that calculates the user; With the be judged as effective power of power, the signal of all effective power is asked variance on the point of the planisphere of their correspondences above certain thresholding; Variance judges that user's signal interference ratio is low during greater than given thresholding, and variance is during less than given thresholding, and the signal interference ratio of judging the user be a height.

The method that the signal interference ratio that utilizes restored symbol level signal to carry out the user is judged has a lot, one of them is: respectively the multipath signal that has recovered is carried out signal interference ratio and estimate, the estimated result of comprehensive each footpath signal interference ratio carries out the judgment processing of user's signal interference ratio, require if user's signal interference ratio surpasses, then can stop to handle and directly carry out symbol judgement output.

The estimation of user's signal interference ratio can be finished by an iterative processing, and detailed process is as follows: the symbol level restoring signal S that at first utilizes d symbol p footpath of k user _{K, p}(d) carry out symbol phase and estimate that phase estimation is ${\mathrm{\φ}}_{k,d}=\underset{\mathrm{\φ}=\{\mathrm{k\π}/2,k=\mathrm{0,1,2,3}\}}{\max }\mathrm{Re}\left\{S_{k,p}\left(d\right)\exp (-\mathrm{j\φ})\right\}$ , next estimates the signal energy in k user p footpath, Energy Estimation is ${\mathrm{power}}_k=|\frac{1}{N}\underset{d=1}{\overset{N}{\mathrm{\Σ}}}{S}_{k,p}\left(d\right)\exp (-j{\mathrm{\φ}}_{k,d}){|}^2$ , wherein N is the symbolic number of user in the time slot, estimates the interference in k user p footpath then, Interference Estimation is $I_k=\frac{1}{N}\underset{d=1}{\overset{N}{\mathrm{\Σ}}}|S_{k,p}\left(d\right)-\underset{j=1}{\overset{J}{\mathrm{\Σ}}}|h_{k,l}^j{|}^2{|}^2$ , then calculate k user's signal interference ratio and estimate, wherein SIR _kInitial value be made as zero, be that the signal interference ratio in k user p footpath is estimated, the SIR on the right of the equation _kIt is last signal interference ratio estimated result.At the signal interference ratio of estimating user signal is that every footpath signal to the user carries out signal interference ratio respectively and estimates that the signal interference ratio in each footpath that will handle is then estimated to add up as this time carrying out the value that signal interference ratio is judged.

What more than introduce is a kind of iteration method of estimation, and the estimation of signal interference ratio also can directly utilize S _k(d) finish, estimation procedure is: the symbol level restoring signal S that at first utilizes d symbol of k user _k(d) carry out symbol phase and estimate that phase estimation is ${\mathrm{\φ}}_{k,d}=\underset{\mathrm{\φ}=\{\mathrm{k\π}/2,k=\mathrm{0,1,2,3}\}}{\max }\mathrm{Re}\left\{S_k\left(d\right)\exp (-\mathrm{j\φ})\right\}$ Next estimates k subscriber signal energy, and Energy Estimation is ${\mathrm{power}}_k=|\frac{1}{N}\underset{d=1}{\overset{N}{\mathrm{\Σ}}}{S}_k\left(d\right)\exp (-j{\mathrm{\φ}}_{k,d}){|}^2$ , wherein N is the symbolic number of user in the time slot; Estimate k user's interference then, Interference Estimation is $I_k=\frac{1}{N}\underset{d=1}{\overset{N}{\mathrm{\Σ}}}|S_k\left(d\right)\exp (-j{\mathrm{\φ}}_{k,d})-\underset{l=1}{\overset{L}{\mathrm{\Σ}}}\underset{j=1}{\overset{J}{\mathrm{\Σ}}}|h_{k,l}^j{|}^2{|}^2$ , wherein L is the multipath number handled, the channel estimation value in this moment this formula must be the channel estimating of the multipath handled, but directly uses l=1 in the formula in order to be reduced at ... L represents these footpaths; Calculate k user's signal interference ratio at last and estimate SIR _k=power _k/ I _k

(8) the strong footpath of reconstruct chip level signal is eliminated the interference of the strong footpath of whole users to weak footpath signal: utilize S ^{K, p}(d), each user of scrambler reconstruct of channel estimation value, each user's in this footpath spreading code and sub-district is based on the chip level signal in the strong footpath of each array element, and eliminates received signal r _j(n) whole users' strong footpath signal is to the interference of untreated multipath signal, promptly in $r_j\left(n\right)=r_j\left(n\right)-\underset{k=1}{\overset{K}{\mathrm{\Σ}}}{S}_{k,p}^j\left(n\right)$ 。In this step, restructuring procedure equally both can be declared the result and realized based on soft, can realize that nature can adopt the reconstruct mode in the step (5) based on declaring the result firmly again, was the S on equation the right with step (5) difference _{K, p}(d) numerical value is different, and employed in this step is the symbol level signal of eliminating d the symbol p footpath of k user of recovering again after the inter-user interference.

(9) execution in step (3) is to (8) repeatedly, and the judgement output condition in satisfying step (7) is recovered all users' signal.

In described step e, G, all mention the strong footpath of reconstruct chip level signal, when being reconstructed, can utilize three kinds of different signals:

First kind is utilize to recover the strong footpath symbol level signal that obtains, adds channel estimating, utilizes each user's the spreading code and the scrambler of sub-district to carry out spectrum-spreading and scrambling again, like this with regard to reconstruct the chip level signal of each user based on the strong footpath of each array element.

Second kind is the multipath symbol level signal after can utilizing merging, adds channel estimating, utilizes each user's the spreading code and the scrambler of sub-district to carry out spectrum-spreading and scrambling again, like this with regard to reconstruct the chip level signal of each user based on the strong footpath of each array element.

The third is the deferred message that can only utilize most powerful path symbol level signal and need the strong footpath of recovery, add channel estimating, utilize each user's the spreading code and the scrambler of sub-district to carry out spectrum-spreading and scrambling again, like this with regard to reconstruct the chip level signal of each user based on the strong footpath of each array element.Amount of calculation is still less for preceding dual mode for the amount of calculation of this mode.

Fig. 3 has provided second kind of flow chart of the baseband processing method that the present invention is based on smart antenna and interference eliminated.The difference of this flow chart and Fig. 1 is: after carrying out multipath merging processing, carry out the judgement of end condition earlier, be reconstructed strong footpath chip level signal again, eliminate the interference of strong footpath to weak footpath.That is to say that the position of step 7 and step 8 is changed.

Fig. 4 has provided the third flow chart of the baseband processing method that the present invention is based on smart antenna and interference eliminated.In this flow chart, its deterministic process is only carried out the judgement of condition b, if only carry out the judgement of condition b, then can mention before the step 3, that is to say: after the channel estimating, carry out the judgement of condition b earlier, if the multipath number of having handled has surpassed the length of channel estimating impulse response or the number of appointment, then do not carry out following step, directly judgement output; Otherwise then strong footpath symbol level signal is recovered in the strong footpath of search, eliminates between strong footpath and disturbs, and multipath merges, and eliminates strong footpath weak footpath is disturbed, as shown in Figure 4.

Claims (17)

1, a kind of interference-eliminating baseband processing method based on smart antenna, it comprises:

A, baseband receiving signals is carried out channel estimating, obtain the channel estimating of each subscriber channel on each array element;

B, utilize channel estimating to search out most powerful path in the untreated multipath signal;

C, utilize the strong footpath information search, obtain each user's strong footpath symbol level signal;

D, each user's of reconstruct strong footpath chip level signal utilizes all users' reconstruction signal to eliminate the strong directly interference of signal of other user in each user's received signal, extracts the symbol level signal in the strong footpath of each user then again;

E, the merging that each user is carried out multipath are respectively handled;

The chip level signal in F, each user's of reconstruct strong footpath, the strong footpath of whole users signal is to the interference of untreated multipath signal in the elimination received signal;

G, execution in step B to F repeatedly.

2, the interference-eliminating baseband processing method based on smart antenna according to claim 1, it is characterized in that: utilize channel estimation value to carry out power among the aforesaid step B earlier and estimate, according to the distribute power situation of estimating, find out the most powerful path of untreated multipath signal again.

3, the interference-eliminating baseband processing method based on smart antenna according to claim 1, it is characterized in that: described step C and D utilize strong footpath information that back searches and each user's spreading code to carry out despreading descrambling and smart antenna algorithm process to received signal, obtain each user's strong footpath symbol level signal.

4, the interference-eliminating baseband processing method based on smart antenna according to claim 3 is characterized in that: the smart antenna algorithm that step C adopted, and by beam forming processing.

5, the interference-eliminating baseband processing method based on smart antenna according to claim 1, it is characterized in that: described step D, F, it is the strong footpath symbol level signal that utilizes recovery to obtain, add channel estimating, utilize each user's the spreading code and the scrambler of sub-district to carry out spectrum-spreading and scrambling again, like this with regard to reconstruct the chip level signal of each user based on the strong footpath of each array element.

6, the interference-eliminating baseband processing method based on smart antenna according to claim 1, it is characterized in that: described step D, F, it is the multipath symbol level signal that utilizes after merging, add channel estimating, utilize each user's the spreading code and the scrambler of sub-district to carry out spectrum-spreading and scrambling again, like this with regard to reconstruct the chip level signal of each user based on the strong footpath of each array element.

7, the interference-eliminating baseband processing method based on smart antenna according to claim 1, it is characterized in that: described step D, F, it is the deferred message that utilizes most powerful path symbol level signal and need the strong footpath of recovery, add channel estimating, utilize each user's the spreading code and the scrambler of sub-district to carry out spectrum-spreading and scrambling again, like this with regard to reconstruct the chip level signal of each user based on the strong footpath of each array element.

8, the interference-eliminating baseband processing method based on smart antenna according to claim 1, it is characterized in that: aforesaid step e also comprises: multipath is judged after merging processing: a, user's signal interference ratio meet the demands; Or b, the multipath number handled surpass the length of channel estimating impulse response or the number of appointment, then recovers all subscriber signal results, otherwise continue execution in step F.

9, the interference-eliminating baseband processing method based on smart antenna according to claim 1, it is characterized in that: aforesaid step F also comprises: the subscriber signal of eliminating after strong footpath signal disturbs the multipath signal that is untreated is judged: a, user's signal interference ratio meet the demands; Or b, the multipath number handled surpass the length of channel estimating impulse response or the number of appointment, then recovers all subscriber signal results, otherwise continue execution in step G.

10, the interference-eliminating baseband processing method based on smart antenna according to claim 1, it is characterized in that: judge earlier before aforesaid step B carries out whether the multipath number of having handled surpasses the length of channel estimating impulse response or the number of appointment, then recover all subscriber signal results in this way, otherwise continue execution in step B.

11, according to claim 1,8,9 or 10 described interference-eliminating baseband processing methods based on smart antenna, it is characterized in that: described steps A is finished by channel estimation module, in channel estimation module, utilize the pilot portion of received signal that each channel is estimated.

12, according to claim 1,8,9 or 10 described interference-eliminating baseband processing methods based on smart antenna, it is characterized in that: described step C is that the spreading code by each user carries out despreading to received signal, and carries out descrambling.

13, according to claim 1,8,9 or 10 described interference-eliminating baseband processing methods based on smart antenna, it is characterized in that: the reconstruct among step D, the F, its restructuring procedure can be declared the result and realizes based on soft, also can realize based on declaring the result firmly.

14, the interference-eliminating baseband processing method based on smart antenna according to claim 13 is characterized in that: the interference eliminated described in step D, the F is the removing method that adopts fixing power or self adaptation power.

15, according to Claim 8 or 9 described interference-eliminating baseband processing methods based on smart antenna, it is characterized in that: utilize restored symbol level signal to judge user's signal interference ratio, can estimate that the estimated result of comprehensive each footpath signal interference ratio carries out the judgment processing of user's signal interference ratio and carries out by respectively the multipath signal that has recovered being carried out signal interference ratio.

16, interference-eliminating baseband processing method based on smart antenna according to claim 15, it is characterized in that: the estimation of above-mentioned user's signal interference ratio can be finished by an iterative processing, at first utilize the symbol level restoring signal in a certain footpath of user symbol to carry out the symbol phase estimation, next estimates the signal energy in this this footpath of user, estimate the interference in this this footpath of user then, the signal interference ratio that calculates this user is estimated, the signal interference ratio of estimating user signal is that the every footpath signal to the user carries out signal interference ratio respectively and estimates that the signal interference ratio in each footpath that will handle is then estimated to add up as this time carrying out the value that signal interference ratio is judged.

17, the interference-eliminating baseband processing method based on smart antenna according to claim 15, it is characterized in that: the estimation of this signal interference ratio also can directly utilize the symbol level restoring signal to finish, at first utilize the symbol level restoring signal of a certain symbol of user to carry out the symbol phase estimation, next estimates this subscriber signal energy, estimates this user's interference then.

Images