CN101742600B - Method for selecting common-frequency cell and mobile terminal - Google Patents

Abstract

The invention discloses a method for selecting a common-frequency cell and a mobile terminal. The method comprises the following steps: determining a processing signal in a first signal except for effective information of a first cell by the terminal, wherein the first signal is transmitted to the terminal by a base station, and the first cell is a cell with highest power in a reference common-frequency cell group of the terminal; acquiring initial channel impulse response of each cell in other cells according to the processing signal and basic training sequences of other cells in the reference common-frequency cell group except for the first cell, and acquiring effective diameter power according to the initial channel impulse response of each cell in other cells; and using the cell with effective diameter power more than a predetermined threshold in other cells and the first cell as a common-frequency cell of the terminal. The method and the mobile terminal can take the cell with high correlation as the common-frequency cell, can effectively improve the performance of common-frequency interference elimination in a simple mode, and solve the problem of abnormality of common-frequency interference elimination.

Description

The system of selection of co-frequency cell and portable terminal

Technical field

The present invention relates to the data network communications field, relate in particular to a kind of system of selection and portable terminal of co-frequency cell.

Background technology

As shown in Figure 1; Be TD-SCDMA (Time Division-Synchronous Code DivisionMultiple Access; Abbreviate TD-SCDMA as) the frame structure sketch map of system, in the TD-SCDMA system, come the capacity of further expansion system through adopting the identical networking technology; Though can increase the capacity of system like this, can bring the problem of phase mutual interference between co-frequency cell simultaneously.

Because the existence of co-frequency cell, terminal must be eliminated with disturbing frequently to guarantee demodulation performance.At present, the base station is through measuring and detect portable terminal, and according to the co-frequency cell tabulation of signal power size configure portable terminal at each time slot, it is that interference cancellation operation is carried out in each sub-district in the co-frequency cell tabulation of its configuration that portable terminal utilizes the base station.But the base station can not consider that in configuration co-frequency cell when tabulation institute the correlation of sub-district carries out the selection of sub-district, after the relatively poor sub-district of correlation is selected into co-frequency cell and tabulates, when carrying out interference eliminated, can cause the result of interference eliminated to occur unusually.

To the sub-district of correlation difference influences the problem of interference eliminated owing to not considering the correlation of sub-district in the tabulation of configuration co-frequency cell in the correlation technique, effective solution is not proposed as yet at present.

Summary of the invention

To the sub-district of correlation difference influences the problem of interference eliminated owing to not considering the correlation of sub-district in the tabulation of configuration co-frequency cell in the correlation technique; The present invention proposes a kind of system of selection and portable terminal of co-frequency cell; Can be that co-frequency cell is selected at the terminal according to the correlation of sub-district, avoid with the unusual problem of frequency interference eliminated.

To the sub-district of correlation difference influences the problem of interference eliminated owing to not considering the correlation of sub-district in the tabulation of configuration co-frequency cell in the correlation technique; The present invention also proposes a kind of selection portable terminal of co-frequency cell; Can be that co-frequency cell is selected at the terminal according to the correlation of sub-district, avoid with the unusual problem of frequency interference eliminated.

Technical scheme of the present invention is achieved in that

A kind of system of selection of co-frequency cell comprises:

The processing signals of the first sub-district effective information is confirmed to remove in first signal in the terminal, and wherein, said first signal sends to said terminal by the base station, the strongest sub-district of power in the reference co-frequency cell group that said first sub-district is said terminal;

Carry out channel estimating to said with reference to each sub-district in other sub-districts except that said first sub-district in the co-frequency cell group according to said processing signals; Obtain the initial channel impulse response of each sub-district in said other sub-districts, and obtain the effective diameter power of this each sub-district according to the initial channel impulse response of each sub-district in said other sub-districts;

With effective diameter power in said other sub-districts greater than Pow _{Max cell}/ Thresh _ACDSub-district and said first sub-district as the co-frequency cell at said terminal, wherein, Pow _{Max cell}Be the effective diameter power of said first sub-district, Thresh _ACDFor activating thresholding in predetermined sub-district.

Preferably, said terminal confirms that the operation of said processing signals comprises:

Said terminal obtains the initial channel impulse response of said first sub-district according to the basic training sequences of said first signal and said first sub-district, and denoising is carried out in the initial channel impulse response of said first sub-district;

Obtain secondary signal according to the said initial channel impulse response after the denoising and the basic training sequences of said first sub-district, and obtain said processing signals according to said first signal and said secondary signal.

Wherein, obtain said secondary signal according to following formula:

Rec _rebuild＝IFFT(FFT(H _{denoise_max?cell}).*FFT(Mid _max?cell))

Wherein, Rec _RebuildBe said secondary signal, H _{Denoise_max cell}Be the said initial channel impulse response after the denoising, Mid _{Max cell}Basic training sequences for said first sub-district.

Wherein, obtain said processing signals according to following formula:

Rec _IC＝Rec _old-Rec _rebuild

Wherein, Rec _ICBe said processing signals, Rec _OldBe said first signal, Rec _RebuildBe said secondary signal.

Wherein, confirm the initial channel impulse response of each sub-district in said other sub-districts according to following formula:

H _{ini_intra_i}＝IFFT(FFT(Rec _IC)./FFT(Mid _{intra_i}))，i＝1…N

Wherein, H _{Ini_intra_i}Be the initial channel impulse response of i sub-district in said other sub-districts, Mid _{Intra_i}Be the basic training sequences of i sub-district, Rec _ICBe said processing signals, N is the number of said other sub-districts.

Preferably, the quantity of said co-frequency cell can demodulation greater than said terminal the situation of largest cell quantity under, said method further comprises:

From said co-frequency cell, select the actual co-frequency cell of M sub-district as said terminal according to effective diameter power order from big to small, wherein, M is the largest cell quantity that said terminal can demodulation.

A kind of portable terminal comprises:

Strong cell selecting device is used for from select the first the strongest sub-district of power as strong sub-district with reference to the co-frequency cell group;

The first initial channel impulse response estimator is used for obtaining according to the basic training sequences of said first signal and said first sub-district initial channel impulse response of said first sub-district;

The signal reconstruction calculator is used for denoising is carried out in the initial channel impulse response of said first sub-district, and obtains secondary signal according to the said initial channel impulse response after the denoising and the basic training sequences of said first sub-district;

The second initial channel impulse response estimator; Be used for obtaining processing signals according to said first signal and said secondary signal; And according to said processing signals and said with reference in the co-frequency cell group except that said first sub-district basic training sequences of other sub-districts; Obtain the initial channel impulse response of each sub-district in said other sub-districts, wherein, said processing signals is to remove the signal of the said first sub-district effective information in said first signal;

Detector is activated in the sub-district, be used for detecting the effective diameter power of each sub-district according to initial channel impulse response with reference to each sub-district of co-frequency cell, with effective diameter power in said other sub-districts greater than Pow _{Max cell}/ Thresh _ACDSub-district and said first sub-district as the co-frequency cell at said terminal, wherein, Pow _{Max cell}Be the effective diameter power of said first sub-district, Thresh _ACDFor activating thresholding in predetermined sub-district.

The present invention is through confirming to receive the co-frequency cell that the processing signals of removing the strongest sub-district of power effective information in the signal obtains the effective diameter power of each sub-district and then confirms this terminal; Sub-district that can correlation is high is as co-frequency cell; Effectively raising is avoided in the correlation technique with the unusual problem of interference eliminated appearance frequently with the performance of frequency interference eliminated.

Description of drawings

Fig. 1 is the frame structure sketch map according to the TD-SCDMA system of prior art;

Fig. 2 is the flow chart of steps according to the system of selection of the co-frequency cell of the embodiment of the invention;

Fig. 3 is the process chart of believing according to the system of selection of the co-frequency cell of the embodiment of the invention;

Fig. 4 is the composition structure connection layout according to the terminal of the embodiment of the invention.

Embodiment

In plurality of communication systems such as the TD-SCDMA system; Network using identical networking technology further enlarges power system capacity; But identical networking can bring the interference between co-frequency cell, and the terminal need be selected the same frequency tabulation of high level configuration in order to improve system's receptivity; How to select co-frequency cell, and the number of co-frequency cell all there is fundamental influence to complexity and the performance of calculating.The present invention is through confirming to receive the co-frequency cell that the processing signals of removing the strongest sub-district of power effective information in the signal obtains the effective diameter power of each sub-district and then confirms this terminal; Sub-district that can correlation is high is effectively improved the performance with the frequency interference eliminated as co-frequency cell with simple mode.

Fig. 2 is the flow chart of steps of system of selection of the co-frequency cell of the embodiment of the invention, and is as shown in Figure 2, and concrete implementation method is following:

Step S201; The processing signals of the first sub-district effective information is confirmed to remove in first signal in the terminal, and wherein, first signal is the reception signal that the base station sends to the terminal; First sub-district is the strongest sub-district of power in the reference co-frequency cell group at terminal; The concrete operations of this step are: the terminal obtains the initial channel impulse response of first sub-district according to the basic training sequences of first signal and first sub-district, and denoising is carried out in the initial channel impulse response of first sub-district, afterwards; Basic training sequences according to the initial channel impulse response after the denoising and first sub-district obtains secondary signal, and obtains processing signals according to first signal and secondary signal.

Step S202; According to processing signals to carrying out channel estimating with reference to each sub-district in other sub-districts except that first sub-district in the co-frequency cell group; Obtain the initial channel impulse response of each sub-district in other sub-districts, and obtain the effective diameter power of this each sub-district according to the initial channel impulse response of each sub-district in other sub-districts.

Step S203, with effective diameter power in other sub-districts greater than Pow _{Max cell}/ Thresh _ACDSub-district and first sub-district as the co-frequency cell at terminal, wherein, Pow _{Max cell}Be the effective diameter power of first sub-district, Thresh _ACDFor activating thresholding in predetermined sub-district, wherein, Thresh _ACDSpan is the natural number between [4,32].

Preferably; The quantity of co-frequency cell can demodulation greater than the terminal the situation of largest cell quantity under; Can from co-frequency cell, select the actual co-frequency cell of M sub-district as the terminal according to effective diameter power order from big to small, wherein, M is the largest cell quantity that the terminal can demodulation.For example; S201 is to step S203 for the process above-mentioned steps; The number of determining the co-frequency cell at terminal is 6, and according to the demodulation ability at terminal, and the largest cell quantity that the terminal can demodulation is 5; Be M=5, then the terminal goes out the actual co-frequency cell of 5 sub-districts as the terminal with these 6 co-frequency cells according to effective diameter power selective sequential from big to small.Again for example, to step S203, the number of determining the co-frequency cell at terminal is 6 through above-mentioned steps S201; And according to the demodulation ability at terminal; The terminal can demodulation largest cell quantity be 7, i.e. M=7, then the terminal with these 6 co-frequency cells all as the actual co-frequency cell at terminal.

Need to prove that the terminal can be selected to carry out the moment of above-mentioned steps S201 to step S203 as required flexibly; For example; A step S201 can be carried out to step S203 by a time slot in the terminal, also can carry out a step S201 to step S203 by at interval several time slots, and perhaps terminal configuration execution in step S201 is to the cycle of step S203; To step S203, execution in step S201 is to step S203 in the time of also can behind starting up of terminal, business being arranged with regard to execution in step S201 for certain hour at interval.And in correlation technique; The co-frequency cell list configuration will can not change in a very long time after well, if during network condition change, will cause the co-frequency cell tabulation can't satisfy the requirement of real-time; Therefore; Through regular execution above-mentioned processing of the present invention, can confirm in real time in time to adapt to the variation of network by co-frequency cell.

Fig. 3 is the process chart of believing according to the system of selection of the co-frequency cell of the embodiment of the invention, and is as shown in Figure 3, comprises following processing:

Step S301; At first tabulate (promptly from the same frequency of high level configuration in the terminal; Reference co-frequency cell group mentioned above) selects a strongest sub-district of power in as strong sub-district (that is, first sub-district mentioned above), for example; High-rise when the configuration co-frequency cell, also carried the historical signal power level of co-frequency cell simultaneously.Maximum signal power intensity corresponding district can be selected in the terminal from the historical signal power level of each sub-district be strong sub-district.

Step S302; The terminal receives from the reception signal of base station (promptly; First signal mentioned above); And be that the middle Midamble sign indicating number (training sequence) of 128chips and the basic Midamble sign indicating number of strong sub-district carry out channel estimating according to length in this reception signal, obtain the initial channel impulse response H of strong sub-district _{Ini_max cell}, for example, can utilize following formula to confirm H _{Ini_max cell}:

H _{Ini_max cell}=IFFT (FFT (Rec _Old)/Mid _{Max cell}) wherein, Rec _OldFor being the middle Midamble sign indicating number of 128chips from length in the reception signal of base station, Mid _{Max cell}Basic Midamble sign indicating number for strong sub-district.

Step S303 carries out denoising to the initial channel impulse response of strong sub-district, and utilizes channel impulse response and the strong above-mentioned reception signal of sub-district basic Midamble code weight structure after the denoising of strong sub-district, obtains reconstruction signal (that is, mentioned above secondary signal).

Particularly; The every some performance number and the noise power threshold value of the initial channel impulse response of strong sub-district compare, if performance number then is changed to 0 with performance number less than this noise power threshold; Otherwise keep this performance number, obtain the channel impulse response H after the denoising of strong sub-district _{Denoise_max cell}, wherein, denoising thresholding Thresh _DenoiseCan for: ${\mathrm{Thresh}}_{\mathrm{Denoise}}=P_{\mathrm{Denoise}}*(\underset{k=0}{\overset{127}{\mathrm{\Σ}}}{\left|h_{\mathrm{Ini}\_\mathrm{Max}\mathrm{Cell}\_k}\right|}^2/128),$ Parameter P wherein _DenoiseBe adjustable parameter, can adjust, and can utilize following formula that denoising is carried out in the initial channel impulse response of strong sub-district to obtain H according to simulation performance _{Denoise_max cell}:

$H_{\mathrm{denoise}\_\max \mathrm{cell}\_k}=\left\{\begin{array}{cc}{H}_{\mathrm{ini}\_\max \mathrm{cell}\_k},& \mathrm{if}{\left|h_{\mathrm{ini}\_\max \mathrm{cell}\_k}\right|}^2>{\mathrm{Thresh}}_{\mathrm{denoise}}\\ 0,& \mathrm{or\; else}\end{array}\right..$

Then, utilize H _{Denoise_max cell}Obtain reconstruction signal with the basic Midamble sign indicating number of strong sub-district, for example, can utilize following formula to obtain reconstruction signal Rec _Rebuild:

Rec _Rebuild=IFFT (FFT (H _{Denoise_max cell}) .*FFT (Mid _{Max cell})) wherein, H _{Denoise_maxcell}Be the channel impulse response after the strong sub-district denoising, Mid _{Max cell}Basic Midamble sign indicating number for strong sub-district.

Step S304 is according to above-mentioned reception signal Rec _DataObtain receiving signal Rec with reconstruction signal _DataThe middle processing signals of removing strong sub-district effective information for example, can utilize following formula to obtain processing signals Rec _IC:

Rec _IC＝Rec _old-Rec _rebuild。

Step S305; For in the co-frequency cell table except that strong sub-district each sub-district in other sub-districts, the basic Midamble sign indicating number according to processing signals and this sub-district obtains the initial channel impulse response of this sub-district; For example, can utilize following formula to confirm the initial channel impulse response of this each sub-district:

H _{Ini_intra_i}=IFFT (FFT (Rec _IC) ./FFT (Mid _{Intra_i})), i=1 ... N, wherein, H _{Ini_intra_i}Be the initial channel impulse response of i sub-district in other sub-districts, Mid _{Intra_i}Be the basic Midamble sign indicating number of i sub-district, Rec _ICBe processing signals, N be in the co-frequency cell table except that strong sub-district the number of other sub-districts.

Step S306; Initial channel impulse response according to strong sub-district; Calculate the effective diameter power of this strong sub-district; And obtain the effective diameter power of each sub-district according to the initial channel impulse response of each sub-district in other sub-districts, and afterwards, with the sub-district and strong sub-district co-frequency cell as terminal of effective diameter power in other sub-districts greater than predetermined threshold.For example, the effective diameter power of each sub-district is (Pow in other sub-districts _{Max cell}, Pow _{Intra_1}..., Pow _{Intra_N}), the effective diameter power of strong sub-district is Pow _{Max cell},

Wherein, the effective diameter power of strong sub-district can obtain through following formula: Pow _{Max cell}=Max (| h _j| ²), wherein, Pow _{Max cell}Be the effective diameter power of strong sub-district, h _jBe the j item in the channel impulse response array after the strong sub-district denoising, j=1,2 ..., 128.

The effective diameter power of other each sub-districts can obtain through following formula: Pow _{Intra_i}=Max (| H _{Ini_intra_i}(j) | ²), wherein, H _{Ini_intra_i}(j) be the numerical value of j item in the channel impulse response array of i sub-district in N the sub-district, j=1,2 ..., 128, i=1 ..., N.

Effective diameter power Pow i sub-district _{Intra_i}When meeting the following conditions, with the co-frequency cell of this sub-district as the terminal, Pow _{Intra_i}＞Pow _{Max cell}/ Thresh _ACD, wherein, parameter Thresh _ACDBe adjustable parameter.

Step S307; The quantity N of co-frequency cell can demodulation greater than the terminal the situation of largest cell quantity under; Can from co-frequency cell, select the actual co-frequency cell of M sub-district as the terminal according to effective diameter power order from big to small, wherein, M is the largest cell quantity that the terminal can demodulation.

Through above-mentioned processing, can further screen the sub-district in the co-frequency cell tabulation of system configuration, effectively improve the correlation of co-frequency cell, improve performance with the frequency interference eliminated.

Fig. 4 is the composition structure chart of following according to the portable terminal of the embodiment of the invention, and is as shown in Figure 4, and this portable terminal comprises:

Strong cell selecting device 401 is used for from select the first the strongest sub-district of power as strong sub-district with reference to the co-frequency cell group;

The first initial channel impulse response estimator 402 is used for obtaining according to the basic training sequences of first signal and first sub-district initial channel impulse response of first sub-district;

Signal reconstruction calculator 403 is used for denoising is carried out in the initial channel impulse response of first sub-district, and obtains secondary signal according to the basic training sequences of the initial channel impulse response after the denoising and first sub-district;

The second initial channel impulse response estimator 404; Be used for obtaining processing signals according to first signal and secondary signal; And according to processing signals and with reference in the co-frequency cell group except that first sub-district basic training sequences of other sub-districts; Obtain the initial channel impulse response of each sub-district in other sub-districts, wherein, processing signals is to remove the signal of the first sub-district effective information in first signal;

Detector 405 is activated in the sub-district, be used for detecting the effective diameter power of each sub-district according to initial channel impulse response with reference to each sub-district of co-frequency cell, with effective diameter power in other sub-districts greater than Pow _{Max cell}/ Thresh _ACDSub-district and first sub-district as the co-frequency cell at terminal, wherein, Pow _{Max cell}Be the effective diameter power of first sub-district, Thresh _ACDFor activating thresholding in predetermined sub-district.

Each device in the portable terminal shown in Figure 4 is realized the selection course of co-frequency cell of the present invention according to following operation principle:

Strong cell selecting device 401 selects the strongest sub-district of power as strong sub-district from the co-frequency cell tabulation of high level configuration; For example; High-rise when the configuration co-frequency cell; Also carried simultaneously the historical signal power level of co-frequency cell, strong cell selecting device 401 can be selected maximum signal power intensity corresponding district from the historical signal power level of each sub-district be strong sub-district.

The reception signal that the first initial channel impulse response estimator 402 receives from the base station; And be that the basic Midamble sign indicating number of the strong sub-district selected in middle Midamble sign indicating number and the strong cell selecting device 401 of 128chips carries out channel estimating according to length in this reception signal, obtain the initial channel impulse response H of strong sub-district _{Ini_max cell}, that is, be the Midamble data Rec of 128chips with receiving length _OldWith strong zone leader be the basic Midamble sign indicating number Mid of 128chips _ServiceBe input in the first initial channel impulse response estimator 402, the algorithm of initial channel impulse response can be realized through the method for prior art.For example, can utilize following formula to confirm H _{Ini_max cell}:

H _{Ini_max cell}=IFFT (FFT (Rec _Old)/Mid _{Max cell}), wherein, Rec _OldFor being the middle Midamble sign indicating number of 128chips from length in the reception signal of base station, Mid _{Max cell}Basic Midamble sign indicating number for strong sub-district.

Signal reconstruction calculator 403; Denoising is carried out in initial channel impulse response to the strong sub-district determined in the first initial channel impulse response estimator 402; And utilize the channel impulse response and the strong above-mentioned reception signal of sub-district basic Midamble code weight structure after the denoising of strong sub-district, obtain reconstruction signal.That is, the initial channel impulse response of strong sub-district is input in the signal reconstruction calculator 403, signal reconstruction calculator 403 at first carries out denoising to the initial channel impulse response of strong sub-district.

Particularly; Signal reconstruction calculator 403 can carry out denoising to the initial channel impulse response of strong sub-district through following manner: the every some performance number and the noise power threshold value of the initial channel impulse response of strong sub-district compare; If performance number is less than this noise power threshold; Then performance number is changed to 0, otherwise keeps this performance number, obtain the channel impulse response H after the denoising of strong sub-district _{Denoise_max cell}, wherein, denoising thresholding Thresh _DenoiseCan for: ${\mathrm{Thresh}}_{\mathrm{Denoise}}=P_{\mathrm{Denoise}}*(\underset{k=0}{\overset{127}{\mathrm{\Σ}}}{\left|h_{\mathrm{Ini}\_\mathrm{Max}\mathrm{Cell}\_k}\right|}^2/128),$ Parameter P wherein _DenoiseBe adjustable parameter, can adjust, and can utilize following formula that denoising is carried out in the initial channel impulse response of strong sub-district to obtain H according to simulation performance _{Denoise_max cell}:

$H_{\mathrm{denoise}\_\max \mathrm{cell}\_k}=\left\{\begin{array}{cc}{H}_{\mathrm{ini}\_\max \mathrm{cell}\_k},& \mathrm{if}{\left|h_{\mathrm{ini}\_\max \mathrm{cell}\_k}\right|}^2>{\mathrm{Thresh}}_{\mathrm{denoise}}\\ 0,& \mathrm{or\; else}\end{array}\right..$

Then, signal reconstruction calculator 403 utilizes H _{Denoise_max cell}Obtain reconstruction signal with the basic Midamble sign indicating number of strong sub-district, for example, can utilize following formula to obtain reconstruction signal Rec _Rebuild:

Rec _Rebuild=IFFT (FFT (H _{Denoise_max cell}) .*FFT (Mid _{Max cell})), wherein, H _{Denoise_max cell}Be the channel impulse response after the strong sub-district denoising, Mid _{Max cell}Basic Midamble sign indicating number for strong sub-district.

The second initial channel impulse response estimator 404 is used for according to above-mentioned reception signal Rec _DataObtain receiving signal Rec with the reconstruction signal that obtains in the signal reconstruction calculator 403 _DataIn remove the processing signals of strong sub-district effective information, and in the co-frequency cell table except that strong sub-district each sub-district in other sub-districts, the basic Midamble sign indicating number according to processing signals and this sub-district obtains the initial channel impulse response of this sub-district,

For example, with original reception signal Rec _DataWith reconstructed received signal Rec _RebuildBe input in the second initial channel impulse response estimator 404, the second initial channel impulse response estimator 404 at first utilizes Rec _Old-Rec _RebuildThe processing signals Rec of strong sub-district effective information is removed _ICThen, the second initial channel impulse response estimator 404 can utilize following formula to confirm the initial channel impulse response of this each sub-district:

H _{Ini_intra_i}=IFFT (FFT (Rec _IC) ./FFT (Mid _{Intra_i})), i=1 ... N, wherein, H _{Ini_intra_i}Be the initial channel impulse response of i sub-district in other sub-districts, Mid _{Intra_i}Be the basic Midamble sign indicating number of i sub-district, Rec _ICBe processing signals, N be in the co-frequency cell table except that strong sub-district the number of other sub-districts.

Detector 405 is activated in the sub-district; Be used for initial channel impulse response according to strong sub-district; Calculate the effective diameter power of this strong sub-district, and obtain the effective diameter power of each sub-district, promptly according to the initial channel impulse response of each sub-district in other sub-districts; The initial channel impulse response of each sub-district in the co-frequency cell tabulation is input to the sub-district activates in the detector 405, detector 405 is activated in the sub-district, and impulse response detects the maximum diameter performance number of each sub-district according to initial channel; Afterwards, with the sub-district and strong sub-district co-frequency cell as terminal of effective diameter power in other sub-districts greater than predetermined threshold.For example, the effective diameter power of each sub-district is (Pow in other sub-districts _{Max cell}, Pow _{Intra_1}..., Pow _{Intra_N}), the effective diameter power of strong sub-district is Pow _{Max cell},

Wherein, the effective diameter power of strong sub-district can obtain through following formula: Pow _{Max cell}=Max (| h _j| ²), wherein, Pow _{Max cell}Be the effective diameter power of strong sub-district, h _jBe the j item in the channel impulse response array after the strong sub-district denoising, j=1,2 ..., 128.

The effective diameter power of other each sub-districts can obtain through following formula: Pow _{Intra_i}=Max (| H _{Ini_intra_i}(j) | ²), wherein, H _{Ini_intra_i}(j) be the numerical value of j item in the channel impulse response array of i sub-district in N the sub-district, j=1,2 ..., 128, i=1 ..., N.

Effective diameter power Pow i sub-district _{Intra_i}When meeting the following conditions, with the co-frequency cell of this sub-district as the terminal, Pow _{Intra_i}＞Pow _{Max cell}/ Thresh _ACD, wherein, parameter Thresh _ACDBe adjustable parameter.

Through said apparatus, can further screen the sub-district in the co-frequency cell tabulation of system configuration, effectively improve the correlation of co-frequency cell, improve performance with the frequency interference eliminated.

In sum; By means of technical scheme of the present invention; Through confirming that the processing signals of removing the strongest sub-district of power effective information in the reception signal obtains the effective diameter power of each sub-district and then the co-frequency cell at definite this terminal, sub-district that can correlation is high is effectively improved together the performance of interference eliminated frequently as co-frequency cell with simple mode; Multiple stationary problem in the solution communications field (for example; Can be applicable to the stationary problem of TD-SCDMA system), and implementation procedure of the present invention is simple, thus can carry out the purpose that reaches the real-time update co-frequency cell with some cycles or rule.

The above is merely preferred embodiment of the present invention, and is in order to restriction the present invention, not all within spirit of the present invention and principle, any modification of being done, is equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (6)

1. the system of selection of a co-frequency cell is characterized in that, comprising:

The processing signals of the first sub-district effective information is confirmed to remove in first signal in the terminal, and wherein, said first signal sends to said terminal by the base station, the strongest sub-district of power in the reference co-frequency cell group that said first sub-district is said terminal;

Carry out channel estimating to said with reference to each sub-district in other sub-districts except that said first sub-district in the co-frequency cell group according to said processing signals; Obtain the initial channel impulse response of each sub-district in said other sub-districts, and obtain the effective diameter power of this each sub-district according to the initial channel impulse response of each sub-district in said other sub-districts;

With effective diameter power in said other sub-districts greater than Pow _{Max cell}/ Thresh _ACDSub-district and said first sub-district as the co-frequency cell at said terminal, wherein, Pow _{Max cell}Be the effective diameter power of said first sub-district, Thresh _ACDFor activating thresholding in predetermined sub-district;

Wherein, said terminal confirms that the operation of said processing signals comprises:

Said terminal obtains the initial channel impulse response of said first sub-district according to the basic training sequences of said first signal and said first sub-district, and denoising is carried out in the initial channel impulse response of said first sub-district;

Obtain secondary signal according to the said initial channel impulse response after the denoising and the basic training sequences of said first sub-district, and obtain said processing signals, wherein, obtain said processing signals according to following formula according to said first signal and said secondary signal:

Rec _IC＝Ree _old-Rec _rebuild

Wherein, Rec _ICBe said processing signals, Rec _OldBe said first signal, Rec _RebuildBe said secondary signal.

2. method according to claim 1 is characterized in that, obtains said secondary signal according to following formula:

Rec _rebuild＝IFFT(FFT(H _{denoise_max?cell})·*FFT(Mid _max?cell))，

Wherein, Rec _RebuildBe said secondary signal, H _{Denoise_max cell}Be the said initial channel impulse response after the denoising, Mid _{Max cell}Be the basic training sequences of said first sub-district, FFT representes Fourier transform, and IFFT representes inverse fourier transform.

3. method according to claim 1 and 2; It is characterized in that; Carry out channel estimating to said with reference to each sub-district in other sub-districts except that said first sub-district in the co-frequency cell group according to said processing signals, the processing that obtains the initial channel impulse response of each sub-district in said other sub-districts comprises:

For said with reference in the co-frequency cell group except that said first sub-district each sub-district in other sub-districts, according to the basic training sequences of said processing signals and said sub-district, obtain the initial channel impulse response of said sub-district.

4. method according to claim 1 and 2 is characterized in that, confirms the initial channel impulse response of each sub-district in said other sub-districts according to following formula:

H _{ini_intra_i}＝IFFT(FFT(Rec _IC)./FFT(Mid _{intra_i}))，i＝1…N

Wherein, H _{Ini_intra_i}Be the initial channel impulse response of i sub-district in said other sub-districts, Mid _{Intra_i}Be the basic training sequences of i sub-district, Rec _ICBe said processing signals.

5. method according to claim 1 and 2 is characterized in that, the quantity of said co-frequency cell can demodulation greater than said terminal the situation of largest cell quantity under, said method further comprises:

From said co-frequency cell, select the actual co-frequency cell of M sub-district as said terminal according to effective diameter power order from big to small, wherein, M is the largest cell quantity that said terminal can demodulation.

6. a portable terminal is characterized in that, comprising:

Strong cell selecting device is used for from select the first the strongest sub-district of power as strong sub-district with reference to the co-frequency cell group;

The first initial channel impulse response estimator is used for obtaining according to the basic training sequences that the base station sends to first signal and said first sub-district of portable terminal the initial channel impulse response of said first sub-district;

The signal reconstruction calculator is used for denoising is carried out in the initial channel impulse response of said first sub-district, and obtains secondary signal according to the said initial channel impulse response after the denoising and the basic training sequences of said first sub-district;

The second initial channel impulse response estimator; Be used for obtaining processing signals according to said first signal and said secondary signal; And according to said processing signals and said with reference in the co-frequency cell group except that said first sub-district basic training sequences of other sub-districts, obtain the initial channel impulse response of each sub-district in said other sub-districts, wherein; Said processing signals is to remove the signal of the said first sub-district effective information in said first signal, and said processing signals obtains according to following formula:

Rec _IC＝Rec _old-Rec _rebuild

Wherein, Rec _ICBe said processing signals, Rec _OldBe said first signal, Rec _RebuildBe said secondary signal;

Detector is activated in the sub-district, be used for detecting the effective diameter power of each sub-district according to initial channel impulse response with reference to each sub-district of co-frequency cell, with effective diameter power in said other sub-districts greater than Pow _{Max cell}/ Thresh _ACDSub-district and said first sub-district as the co-frequency cell at said terminal, wherein, Pow _{Max cell}Be the effective diameter power of said first sub-district, Thresh _ACDFor activating thresholding in predetermined sub-district.

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