WO2011160340A1

WO2011160340A1 - Method and apparatus for implementing common frequency measurements in time division synchronous code division multiple access (td-scdma) system

Info

Publication number: WO2011160340A1
Application number: PCT/CN2010/076894
Authority: WO
Inventors: 梁立宏
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-06-21
Filing date: 2010-09-14
Publication date: 2011-12-29
Also published as: CN102291161B; CN102291161A

Abstract

A method and an apparatus for implementing common frequency measurements in a Time Division Synchronous Code Division Multiple Access (TD-SCDMA) system are provided. The method includes: receiving signals of multiple cells, implementing Parallel Interference Cancellation (PIC) processing for each cell, and obtaining the first level channel estimation value of each cell (101); according to the first level channel estimation value of each cell, implementing Successive Interference Cancellation (SIC) processing for each PIC-processed cell, and obtaining a channel estimation result of each cell (102); according to the channel estimation result of each cell, obtaining the value of the Primary Common Control Physical Channel Received Signal Code Power (PCCPCH-RSCP) of the corresponding cell (103). By implementing the PIC and the dynamic sorting SIC processing for the received signals of the multiple cells in sequence, the solution obtains accurate PCCPCH-RSCP values, which improves the measurement accuracy of the strong signal cells on the premise of guaranteeing the measurement accuracy of the weak signal cells.

Description

Method and device for performing same frequency measurement in TD-SCDMA system

The present invention relates to the field of wireless communications, and in particular, to a method and apparatus for performing intra-frequency measurement in a TD-SCDMA (Time Division Synchronous Code Division Multiple Access) system. Background technique

In order to improve the spectrum utilization rate, the TD-SCDMA system uses the same-frequency networking technology as an effective solution, but the same-frequency networking technology also brings about the same-frequency interference problem while improving the spectrum utilization rate. Co-channel interference is the signal interference between different cells caused by neighboring co-frequency cells using the same carrier frequency for data transmission. The same-frequency interference will degrade system performance.

On the other hand, in order to improve user experience and support mobile communication, reselection and handover between intra-frequency cells is required in the TD-SCDMA system. The cell reselection means that the UE (User Equipment) selects a best cell to provide services by monitoring the signal quality of the local cell and the neighboring cell at any time in the idle mode; the cell handover refers to when the UE moves from a cell to a cell. In another cell, channel switching is required in order to keep the UE's communication uninterrupted.

The value of the received signal code (RSCP) on the PCCPCH (Primary Common Control Physical Channel) is used to identify the strength of the cell signal, and the reselection or handover performance between the same frequency cells. The accuracy of the measurement result of the PCCPCH-RSCP value of the current cell and the intra-frequency neighboring cell depending on the same frequency measurement. In the prior art, the measured value of PCCPCH-RSCP is calculated by using the channel estimation tap value in the first channel window of the channel estimation value on the midamble code (training sequence code) in the TS0 slot.

In TD-SCDMA systems, single-cell channel estimation is usually done using the classical Steiner channel estimator, which is a low-cost channel estimation method. The basic principle is: The basic midamble code constructs the midamble code of each cell according to a certain rule, so that the matrix of the midamble code system at the receiving end has cyclic correlation, and passes FFT (Fast Fourier Transform) and IFFT (Inverse Fast Fourier). Transform, Inverse Fast Fourier Transform) calculates the channel estimates quickly. The specific calculation process is as follows: The Steiner channel estimator performs frequency domain calculation first, and then obtains the time domain channel estimation value through the IFFT inverse transform. Finally, the channel estimation result is removed by channel estimation and the channel estimation result is obtained.

For the current cell with the same-frequency neighboring cell signal interference, in addition to the TS0 slot signal of the local cell, there is also a TS0 slot signal of the neighboring cell, so it is necessary to perform joint channel estimation of multiple intra-frequency cells. In order to get a more accurate channel estimation result. The joint channel estimation of multiple co-frequency cells generally adopts two structures: SIC (Successive Interference Cancellation) or PIC (Parallel Interference Cancellation).

The SIC generally uses a method of gradually subtracting the maximum user interference, and the SIC detector performs data decision on the received multiple user signals one by one, and then recreates one after the decision, and subtracts the user reconstructed signal according to the order of the signal power. First, the signal with high power is operated first, so that the signal with the weakest power benefits the most, and the signal with the strongest power has the least benefit. Therefore, the detection performance of the SIC for the weak signal is better, and the detection performance for the strong signal is poor. Moreover, the reordering needs to be performed when the signal power changes. In addition, if the initial data decision is unreliable during the SIC processing, a large interference will be generated to the lower stage, thereby causing the performance of the subsequent stages to be degraded.

PIC generally uses the method of simultaneous decision, regeneration and cancellation for each stage. That is, the PIC constructs the interference signal of all users by using the information of the previous stage decision, and then cancels the interference signal from the received signal, and finally judges at the same time. Since PIC uses parallel processing of signal interference, there is no need to sort the processed signals, so PIC has poor detection capability for weak signals. When power control is not ideal, such as in multipath channels, PIC performance is worse than SIC. . Summary of the invention

In view of this, the main object of the present invention is to provide a method and apparatus for performing on-frequency measurement in a TD-SCDMA system, which aims to solve the PCCPCH-RSCP value for a strong signal cell in the same-frequency multi-cell scenario in the prior art. The problem that the weak signal cell cannot be balanced.

In order to solve the above technical problem, the technical solution of the present invention is implemented as follows:

A method for performing on-frequency measurement in a time division synchronous code division multiple access (OFDM) TD-SCDMA system includes the following steps: receiving a multi-cell signal, and performing parallel interference cancellation PIC processing on each cell to obtain a first-level channel estimation of each cell a value; performing, according to the first-level channel estimation value of each cell, the PIC-processed cells, performing subsequent serial interference, and performing SIC processing on each cell to obtain channel estimation results of each cell; and acquiring the main cell according to the channel estimation result of each cell The common control physical channel receives the signal code channel power PCCPCH-RSCP value.

The step of performing PIC processing on each cell to obtain a first-level channel estimation value of each cell specifically includes: performing Fast Fourier Transform FFT and Fast Fourier according to the received multi-cell signal and the basic training sequence midamble code of each cell Inverting the IFFT to obtain the original channel estimation of each cell; performing denoising on the original channel estimation values of each cell to obtain the first-level channel estimation values of each cell, and each channel estimation value has 128 channel estimation tap values.

The step of performing subsequent SIC processing on each PIC processed cell according to the first-level channel estimation value of each cell, and obtaining the channel estimation result of each cell specifically includes: 128 out of the first-level channel estimation values of each cell The channel estimation tap value is used for energy accumulation to obtain a first energy accumulation value; each cell is sorted according to the first energy accumulation value from large to small; and the sorted cells are sequentially subjected to SIC processing to obtain channel estimation values of each cell at the current level. And subtracting the channel estimation tap value corresponding to the previous channel estimation value of each cell to obtain 128 channel estimation tap difference values of consecutive two-stage channel estimation values of each cell; and comparing two consecutive channel estimation values of each cell The 128 channel estimation tap difference values are used for energy accumulation to obtain a second energy accumulation value; each cell is sorted according to the second energy accumulation value from small to large; when the second energy accumulation value of each cell is smaller than the preset When the threshold or interference cancellation reaches a predetermined number of levels, the SIC processing flow is exited, and the channel estimation value of each cell is the channel estimation result of each cell; otherwise, the interference is eliminated for each of the sorted cells. The step of obtaining the channel estimation value of each cell at the current level.

The step of sequentially performing the SIC processing on each of the sorted cells to obtain the channel estimation value of each cell of the cell includes: reconstructing each of the cells other than the current processing cell according to the basic midamble code of each cell and the latest channel estimation value. a cell signal; performing SIC processing according to the reconstructed signal to obtain an interference cancellation result; calculating an initial channel estimation value of the currently processed cell according to the interference cancellation result and the basic midamble code of the currently processed cell; and initial channel estimation for the currently processed cell The value is denoised to obtain the current channel estimation value of the currently processed cell. The above steps are repeated, and each cell is sequentially subjected to SIC processing to obtain a channel estimation value of each cell.

The step of acquiring the PCCPCH-RSCP value of the corresponding cell according to the channel estimation result of each cell specifically includes: performing energy accumulation on the 16 tap values of the first channel estimation window in the channel estimation result, to obtain a third energy accumulated value, where The third energy accumulated value is the PCCPCH-RSCP value of the corresponding cell.

A device for performing intra-frequency measurement in a TD-SCDMA system, comprising: a PIC processing module, configured to receive a multi-cell signal, and perform PIC processing on each cell to obtain a first-level channel estimation value of each cell; and an SIC processing module Performing subsequent SIC processing on each PIC processed cell according to the first-level channel estimation value of each cell to obtain channel estimation results of each cell; and acquiring, configured to acquire PCCPCH-RSCP value of the corresponding cell according to the channel estimation result of each cell .

The PIC processing module specifically includes: a receiving unit, configured to receive a multi-cell signal; a first calculating unit, configured to obtain, by using the FFT and the IFFT, the original channel of each cell according to the received multi-cell signal and the basic midamble code of each cell Estimating; the denoising processing unit is configured to perform denoising processing on the original channel estimation values of the cells to obtain first-level channel estimation values of the respective cells, and each channel estimation value has 128 channel estimation tap values.

The SIC processing module specifically includes: a second calculating unit, configured to be used for the first level of each cell The 128 channel estimation tap values in the channel estimation value are energy accumulated to obtain a first energy accumulation value; the first sorting unit is configured to sort each cell according to the first energy accumulation value from large to small; the interference cancellation unit uses The SIC processing is performed on each of the sorted cells to obtain the channel estimation value of each cell, and the third calculating unit is configured to subtract the channel estimation value of each channel from the channel estimation tap value corresponding to the previous channel estimation value, Obtaining 128 channel estimation tap differences of consecutive two-stage channel estimation values of each cell; a fourth calculating unit, configured to perform energy accumulation on 128 channel estimation tap difference values of consecutive two-stage channel estimation values of each cell to obtain second energy The second sorting unit is configured to sort the cells according to the second energy accumulation value from small to large; the determining unit is configured to: when the second energy accumulation value of each cell is less than a preset threshold or the interference cancellation reaches a predetermined level When counting, the SIC processing procedure is exited, and the channel estimation value of each cell is the channel estimation result of each cell; otherwise, the interference cancellation unit Each cell sorted sequentially SIC process, the small Qu Benji obtained channel estimation value.

The interference cancellation unit specifically includes: a reconstruction subunit, configured to reconstruct, according to the basic midamble code of each cell and the latest channel estimation value, each cell signal except the current processing cell; Performing SIC processing according to the reconstructed signal to obtain an interference cancellation result; a calculation subunit, configured to calculate, according to the interference cancellation result and the basic midamble code of the currently processed cell, to obtain an initial channel estimation value of the currently processed cell; And a processing subunit, configured to perform denoising processing on the initial channel estimation value of the currently processed cell, to obtain a current channel estimation value of the currently processed cell.

The acquiring module is specifically configured to: perform energy accumulation on the 16 tap values of the first channel estimation window in the channel estimation result to obtain a third energy accumulated value, where the third energy accumulated value is the PCCPCH-RSCP of the corresponding cell. value.

The present invention relates to a method and apparatus for performing on-frequency measurement in a TD-SCDMA system, which performs PIC and SIC processing on a received multi-cell signal in sequence, and in the SIC processing, dynamically adjusts interference and eliminates the sequence, Each cell performs multi-level interference and ί 消消 until each cell has two consecutive levels The energy accumulation value of the 128 channel estimation tap difference values of the channel estimation value is less than the preset threshold value or the interference ί 消达到 reaches the predetermined number of stages, and the accurate PCCPCH-RSCP value is obtained, which is the premise of ensuring the measurement accuracy of the weak signal cell. Next, the measurement accuracy of the strong signal cell is improved. DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a flow chart showing an embodiment of a method for performing intra-frequency measurement in a TD-SCDMA system of the present invention;

2 is a schematic diagram showing the specific flow of step 101 in the method for performing the same frequency measurement in the TD-SCDMA system shown in FIG. 1;

3 is a schematic diagram showing a specific flow of step 102 in the method for performing the same frequency measurement in the TD-SCDMA system shown in FIG. 1;

4 is a schematic diagram of a specific process of step 1023 in the method step 102 of performing the same frequency measurement in the TD-SCDMA system shown in FIG. 3;

Figure 5 is a block diagram showing an embodiment of an apparatus for performing the same frequency measurement in the TD-SCDMA system of the present invention;

6 is a schematic diagram showing the specific structure of a PIC processing module in a device for performing the same frequency measurement in the TD-SCDMA system shown in FIG. 5;

7 is a schematic diagram showing the specific structure of an SIC processing module in a device for performing the same frequency measurement in the TD-SCDMA system shown in FIG. 5;

Fig. 8 is a view showing the specific structure of an interference canceling unit in the SIC processing module in the apparatus for performing the same frequency measurement in the TD-SCDMA system shown in Fig. 7. detailed description

The solution of the embodiment of the present invention is mainly: performing PIC and SIC processing on the received multi-cell signal in sequence, and performing multi-level interference and cancellation on each cell in the SIC processing until the channel estimation value of each cell is continuous. The energy accumulation of the 128 channel estimation tap differences is less than the preset The threshold or interference cancellation reaches a predetermined number of levels, and the channel estimation result of each cell is obtained, and the PCCPCH-RSCP value is obtained according to the channel estimation result of each cell.

In order to make the technical solutions of the present invention clearer and clearer, the following will be further described in detail with reference to the accompanying drawings.

As shown in FIG. 1, an embodiment of the present invention provides a method for performing intra-frequency measurement in a TD-SCDMA system, including:

Step 101: Receive a multi-cell signal, and perform PIC processing on each cell to obtain a first-level channel estimation value of each cell.

In this embodiment, in order to improve the measurement accuracy in the same-frequency scenario, the cell to be tested needs to be interfered with, and the cell to be tested includes the current cell and the same-frequency neighboring cell, and is processed by the multi-cell channel estimator. The capability is limited. Only a certain number of cell signals can be processed at a time, for example, 4 cells are processed at a time. Therefore, when there are a large number of cells to be tested, for example, there are 16 cells to be tested, the cells to be tested are subjected to packet processing. This embodiment will be described by taking four cells at a time as an example.

First (first stage processing), PIC channel estimation is performed on four cell signals, and channel estimation is performed using a classical Steiner channel estimator to obtain 128 channel estimation tap values of each cell. It should be noted that, for each received cell signal, the PIC structure is first used for channel estimation processing, which can reduce channel estimation accuracy of each cell in the subsequent stages due to inaccurate channel estimation of the first stage of the first stage under strong interference. The impact.

Step 102: Perform subsequent SIC processing on each PIC processed cell according to the first-level channel estimation value of each cell, and obtain channel estimation results of each cell.

This step will be specifically described below in conjunction with FIG. 3.

Step 103: Acquire a PCCPCH-RSCP value of the corresponding cell according to the channel estimation result of each cell.

In this step, the 16 tap values of the first channel estimation window in the channel estimation result are enabled. The amount is accumulated to obtain a third energy accumulated value, and the third energy accumulated value is the corresponding cell

PCCPCH-RSCP value.

As shown in FIG. 2, step 101 specifically includes:

Step 1011: Receive a multi-cell signal.

Step 1012: Obtain original channel estimation of each cell by performing FFT and IFFT according to the received multi-cell signal and the basic midamble code of each cell.

Step 1013: Perform denoising on the original channel estimation of each cell to obtain a first-level channel estimation value of each cell.

Wherein each channel estimate has 128 channel estimation tap values.

As shown in FIG. 3, step 102 specifically includes:

Step 1021: Perform energy accumulation on 128 channel estimation tap values in the first-level channel estimation values of the cells to obtain a first energy accumulated value.

Step 1022: Sort each cell according to the first energy accumulation value from large to small; Step 1023, sequentially perform SIC processing on each sorted cell to obtain an estimated channel value of each cell;

Step 1024: Subtracting the channel estimation value of each cell from the channel estimation tap value corresponding to the previous channel estimation value, and obtaining 128 channel estimation tap difference values of consecutive two-stage channel estimation values of each cell; Step 1025, continuously The 128 channel estimation tap values of the two-stage channel estimation value are energy accumulated to obtain a second energy accumulated value;

Step 1026: Sort each cell according to the second energy accumulation value from small to large; Step 1027, determine whether the second energy accumulation value of each cell is less than a preset threshold or whether the interference cancellation reaches a predetermined level; if yes, enter Step 1028; otherwise, proceed to step 1023.

In step 1028, the SIC processing flow is exited, and the channel estimation value of each cell is the channel estimation result of each cell.

In the above steps 1021 to 1028, the first stage of each cell after the PIC processing is first performed. The 128 channel estimation tap values in the channel estimation value are subjected to energy accumulation to obtain a first energy accumulation value, and the cells are sorted according to the first energy accumulation value from large to small, and the SIC processing is sequentially performed on each of the sorted cells to obtain The current channel estimation value of each cell, and then the current channel estimation value of each cell and the previous channel estimation value (it should be noted that if the first round of SIC interference cancellation, the pre-channel estimation value is PIC processed The first-stage channel estimation value is subtracted corresponding to the channel estimation tap value, and 128 channel estimation tap difference values of consecutive two-stage channel estimation values of each cell are obtained, and 128 channel estimation tap difference values of consecutive two-stage channel estimation values of each cell are obtained. Performing energy accumulation to obtain a second energy accumulation value, sorting each cell according to the second energy accumulation value from small to large, and proceeding to the next round of interference cancellation processing procedure until 128 channel estimation taps of consecutive two-stage channel estimation values of all cells The energy accumulated value of the difference is less than the preset threshold or the interference cancellation reaches a predetermined number of times.

As shown in FIG. 4, in the embodiment, the foregoing step 1023 specifically includes:

Step 10231: Reconfigure each cell signal except the currently processed cell according to the basic midamble code of each cell and the latest channel estimation value.

Step 10232: Perform SIC processing according to the reconstructed signal to obtain an interference cancellation result; Step 10233, perform calculation according to the interference cancellation result and the basic midamble code of the currently processed cell, to obtain an initial channel estimation value of the currently processed cell;

Step 10234, performing denoising processing on the initial channel estimation value of the currently processed cell, to obtain a current channel estimation value of the current processing cell;

Step 10235: Determine whether all cell interference cancellation processing is completed; if yes, exit the program, otherwise, proceed to step 10231 to perform interference on the next cell.

Ρ

The technical solution of the embodiment of the present invention is specifically described below by using: = 8 as an example, wherein

K = 128 is the basic midamble code length, = 16 is the channel estimation window length, 4 cells are processed at a time, there are 16 cells to be tested, and the predetermined interference cancellation level is 4, that is, the maximum level 4 interference cancellation processing is performed. The specific processing steps are as follows:

In the first step, 16 cells are divided into 4 groups, which are 1 ~ 4, 5 ~ 8 , 9 ~ 12 , 13 - 16 respectively; the second step is to perform the first level interference cancellation processing, using the PIC structure, according to the received The midamble code partial data and the basic midamble code of each cell calculate the original channel estimation value of each cell:

First calculate the frequency domain value of the received midamble portion of 128chip received_midamble value received midamble fft:

The received channel midamble fft = #t(received_midamble)

Channel = ifft(received_midamble_fft . /basic_midamble_fft) ( 2 ) where basic_midamble_fft is the basic midamble code frequency domain value corresponding to a cell, and ./ indicates the division of the two array corresponding numbers.

Performing channel estimation on the obtained time domain signal to perform denoising to obtain a first-stage channel estimation value of each cell;

The channel estimation post-processing compares the result of the channel estimation with a preset threshold, and the channel estimation tap value smaller than the threshold is set to zero. A channel estimation value channel (l: 128, i) of up to 4 cells is obtained, where i = 1, 2, 3, 4, indicating a cell index number.

In the third step, the SIC structure is used to perform interference on each cell, and the channel estimation result of each cell is obtained.

First, the first level of SIC interference, the energy accumulation of 128 channel estimation tap values in the first-level channel estimation values of each cell, to obtain the first energy accumulation value, as shown in formula (3), Each cell sorts according to the first energy accumulation value from large to small;

128

Power (i) - ^ real (channel (k, ί)) ² -imag (channel (k, ί)) ² ( 3 ) Secondly, subsequent SIC interference cancellation: Interfering with the above-mentioned sorted cells in sequence The offset processing is performed to obtain the channel estimation value of each cell; the channel estimation value of each cell and the pre-channel channel estimation value are obtained (the first-stage SIC interference is eliminated, and the pre-channel channel estimation value of each cell is PIC processed) The first-stage channel estimation value is subtracted corresponding to the channel estimation tap value, and 128 channel estimation tap difference values of consecutive two-stage channel estimation values of each cell are obtained; 128 channel estimation tap difference values of consecutive two-stage channel estimation values of each cell are obtained. The energy accumulation is performed to obtain a second energy accumulation value, as shown in the formula (4); the cells are sorted according to the second energy accumulation value from small to large.

Power _n (/)

128

= ^ [real (channel _n (k, /)) - real (channel^ (k, i))f + [imag (channel _n (k, /)) - imag (channel^ (k, /))]

(4) where n is the number of stages of interference cancellation, and the PIC processing step is set to the first stage interference cancellation, so in the SIC interference cancellation processing, n=2, 3, 4;

The above SIC interference cancellation process is repeated until the energy accumulation value of the 128 channel estimation tap differences of the continuous two-stage channel estimation values of all cells is less than a preset threshold value or the level 4 interference cancellation is completed. In this embodiment, the preset threshold value may be determined according to simulation or testing. Finally, the channel estimation result of each cell, that is, the channel estimation value obtained by the last round of interference cancellation is obtained.

In the fourth step, the PCCPCH-RSCP value of the corresponding cell is obtained according to the channel estimation result of each cell: the 16 tap values of the first channel estimation window of each cell channel estimation result are energy-accumulated to obtain a third energy accumulated value, that is, The PCCPCH-RSCP value of the corresponding cell.

In the fifth step, the second to fourth steps are repeated, and the other groups of cells are separately processed until all the packets are processed.

In the third step, the subsequent SIC interference cancellation is performed, and the SIC processing is performed on each of the sorted cells in sequence, and the process of obtaining the channel estimation values of each cell is:

Reconstructing each cell signal except the current processing cell according to the basic midamble code of each cell and the latest channel estimation value;

SIC processing is performed according to the reconstructed signal, and the interference is obtained.

Calculated based on the interference cancellation result and the basic midamble code of the currently processed cell, The initial channel estimate of the current processing cell;

Denoising the initial channel estimation value of the currently processed cell to obtain a current channel estimation value of the currently processed cell;

The above steps are repeated, and each cell is sequentially subjected to SIC processing to obtain a channel estimation value of each cell.

In the embodiment of the present invention, the PIC and SIC processes are sequentially performed on the received multi-cell signal, and in the SIC processing, the interference adjustment sequence is dynamically adjusted, and multi-level interference is cancelled for each cell until two consecutive channels of each cell are used. The energy accumulation value of the estimated 128 channel estimation tap differences is less than the preset threshold or the interference cancellation reaches a predetermined number of stages, and the accurate PCCPCH-RSCP value is obtained, which is improved under the premise of ensuring the measurement accuracy of the weak signal cell. Measurement accuracy of strong signal cells.

As shown in FIG. 5, an embodiment of the present invention provides a device for performing intra-frequency measurement in a TD-SCDMA system, including:

The PIC processing module 501 is configured to receive the multi-cell signal, and perform PIC processing on each cell to obtain a first-level channel estimation value of each cell;

The SIC processing module 502 is configured to perform subsequent SIC processing on each PIC processed cell according to the first-level channel estimation value of each cell, to obtain channel estimation results of each cell;

The obtaining module 503 is configured to obtain a PCCPCH-RSCP value of the corresponding cell according to the channel estimation result of each cell. In this embodiment, the obtaining module 503 is specifically configured to perform energy accumulation on the 16 tap values of the first channel estimation window in the channel estimation result to obtain a third energy accumulated value, where the third energy accumulated value is the corresponding cell. PCCPCH-RSCP value.

As shown in FIG. 6, the PIC processing module 501 specifically includes:

The receiving unit 5011 is configured to receive a multi-cell signal.

a first calculating unit 5012, configured to obtain, by using the FFT and the IFFT, the original channel estimation of each cell according to the received multi-cell signal and the basic training sequence midamble code of each cell; The denoising processing unit 5013 is configured to perform denoising processing on the original channel estimation of each cell to obtain first-level channel estimation values of the respective cells, and each channel estimation value has 128 channel estimation tap values.

As shown in FIG. 7, the SIC processing module 502 specifically includes:

a second calculating unit 5021, configured to perform energy accumulation on 128 channel estimation tap values in the first-level channel estimation values of the cells, to obtain a first energy accumulated value;

a first sorting unit 5022, configured to sort each cell according to a first energy accumulation value from largest to smallest;

The interference cancellation unit 5023 is configured to sequentially perform SIC processing on each sorted cell to obtain an estimated channel value of each channel of each cell;

The third calculating unit 5024 is configured to subtract the channel estimation value of each cell from the channel estimation tap value corresponding to the previous channel estimation value, and obtain 128 channel estimation tap difference values of consecutive two channel estimation values of each cell;

a fourth calculating unit 5025, configured to perform energy accumulation on 128 channel estimation tap differences of consecutive two-stage channel estimation values of each cell to obtain a second energy accumulated value;

a second sorting unit 5026, configured to sort each cell according to a second energy accumulation value from small to large;

The determining unit 5027 is configured to exit the SIC processing procedure when the second energy accumulation value of each cell is less than a preset threshold or the interference ί 消 reaches a predetermined number of stages, and the channel estimation value of each cell is a channel of each cell. The result is estimated; otherwise, the interference cancellation unit 5023 sequentially performs interference cancellation processing on each of the sorted cells to obtain a channel estimation value of each cell.

As shown in FIG. 8, the interference unit 5023 specifically includes:

The reconstruction subunit 50231 is configured to reconstruct, according to the basic midamble code of each cell and the latest channel estimation value, each cell signal except the currently processed cell;

The interference cancellation subunit 50232 is configured to perform SIC processing according to the reconstructed signal to obtain an interference cancellation result; The calculating subunit 50233 is configured to calculate, according to the interference cancellation result and the basic midamble code of the currently processed cell, to obtain an initial channel estimation value of the currently processed cell;

The denoising processing sub-unit 50234 is configured to perform denoising processing on the initial channel estimation value of the currently processed cell to obtain a current channel estimation value of the currently processed cell.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the invention, and equivalent structural or process changes made by the present specification and the drawings may be directly or indirectly applied to other related technical fields. The same is included in the scope of patent protection of the present invention.

Claims

Claim

1. A time division synchronous code division multiple access method A method for performing the same frequency measurement in a TD-SCDMA system, characterized in that the method comprises the following steps:

Receiving a multi-cell signal, and performing parallel interference cancellation PIC processing on each cell to obtain a first-stage channel estimation value of each cell;

Performing subsequent interferences on the PIC-processed cells according to the first-level channel estimation values of the cells, and performing SIC processing to obtain channel estimation results of each cell;

Obtaining a primary common control physical channel received signal channel power PCCPCH-RSCP value of the corresponding cell according to the channel estimation result of each cell.

The method according to claim 1, wherein the step of performing PIC processing on each cell to obtain a first-level channel estimation value of each cell specifically includes:

Decoding the original channel estimates of each cell by using a fast Fourier transform FFT and an inverse fast Fourier transform (IFFT) according to the received multi-cell signal and the basic training sequence midamble code of each cell. The first stage channel estimation values of the respective cells are obtained, and each channel estimation value has 128 channel estimation tap values.

The method according to claim 1 or 2, wherein the step of performing SIC processing on each of the PIC-processed cells according to the first-level channel estimation value of each cell to obtain channel estimation results of each cell is performed. Specifically include:

Performing energy accumulation on 128 channel estimation tap values in the first-level channel estimation values of the cells to obtain a first energy accumulated value;

Sorting each cell according to a first energy accumulation value from large to small;

Performing SIC processing on the sorted cells in sequence to obtain channel estimation values of the current cells of each cell; and subtracting channel estimation values corresponding to the channel estimation values of the previous channel from each channel to obtain successive channel estimations of each cell 128 channel estimates of the value of the difference;

Performing energy estimation on 128 channel estimation tap differences of successive two-stage channel estimation values of each cell Adding, obtaining a second energy accumulated value;

Sorting each cell according to the second energy accumulation value from small to large;

When the second energy accumulation value of each cell is less than the preset threshold or the interference cancellation reaches a predetermined level, the SIC processing flow is exited, and the channel estimation value of each cell is the channel estimation result of each cell; otherwise,

The process of sequentially performing interference cancellation processing on each of the sorted cells to obtain an estimated channel value of each channel of each cell is returned.

The method according to claim 3, wherein the step of sequentially performing SIC processing on each of the sorted cells to obtain the channel estimation value of each cell of the cell includes:

Calculating according to the interference cancellation result and the basic midamble code of the currently processed cell, to obtain an initial channel estimation value of the currently processed cell;

The method according to claim 1 or 2, wherein the step of acquiring the PCCPCH-RSCP value of the corresponding cell according to the channel estimation result of each cell specifically includes:

And accumulating the 16 tap values of the first channel estimation window in the channel estimation result to obtain a third energy accumulated value, where the third energy accumulated value is the PCCPCH-RSCP value of the corresponding cell.

A device for performing on-frequency measurement in a TD-SCDMA system, comprising: a PIC processing module, configured to receive a multi-cell signal, and perform PIC processing on each cell to obtain First channel estimation value of each cell;

The SIC processing module is configured to perform subsequent SIC processing on each PIC processed cell according to the first-level channel estimation value of each cell, to obtain channel estimation results of each cell;

An acquiring module, configured to acquire, according to a channel estimation result of each cell, a corresponding cell

PCCPCH-RSCP value.

The device according to claim 6, wherein the PIC processing module specifically includes:

a receiving unit, configured to receive a multi-cell signal;

a first calculating unit, configured to obtain, by using the FFT and the IFFT, the original channel estimation of each cell according to the received multi-cell signal and the basic midamble code of each cell;

The denoising processing unit is configured to perform denoising processing on the original channel estimation values of the cells to obtain first-level channel estimation values of the respective cells, and each channel estimation value has 128 channel estimation tap values.

The device according to claim 6 or 7, wherein the SIC processing module specifically includes:

a second calculating unit, configured to perform energy accumulation on the 128 channel estimation tap values in the first-level channel estimation values of the cells, to obtain a first energy accumulated value;

a first sorting unit, configured to sort the cells according to the first energy accumulation value from the largest to the smallest; the interference cancellation unit is configured to sequentially perform SIC processing on the sorted cells to obtain the channel estimation values of the respective cells;

a third calculating unit, configured to subtract the channel estimation value of each channel from the channel estimation tap value corresponding to the previous channel estimation value, and obtain 128 channel estimation tap difference values of consecutive two-stage channel estimation values of each cell;

a fourth calculating unit, configured to perform energy accumulation on 128 channel estimation tap differences of consecutive two-stage channel estimation values of each cell to obtain a second energy accumulated value;

a second sorting unit, configured to sort each cell according to a second energy accumulation value from small to large; a judging unit, configured to: when the second energy accumulating value of each cell is less than a preset threshold or the interference cancellation reaches a predetermined level, exiting the SIC processing procedure, the channel estimation value of each cell is a channel estimation result of each cell; The interference cancellation unit sequentially performs SIC processing on each of the sorted cells to obtain an estimated channel value of each channel of each cell.

The apparatus according to claim 8, wherein the interference cancellation unit specifically includes:

a reconstruction subunit, configured to reconstruct, according to a basic midamble code of each cell and a latest channel estimation value, each cell signal except the currently processed cell;

An interference cancellation subunit, configured to perform SIC processing according to the reconstructed signal to obtain an interference cancellation result;

a calculating subunit, configured to perform, according to the interference cancellation result and the basic midamble code of the currently processed cell, to obtain an initial channel estimation value of the currently processed cell;

The denoising processing sub-unit is configured to perform denoising processing on the initial channel estimation value of the currently processed cell to obtain a current channel estimation value of the currently processed cell.

10. The device according to claim 6 or 7, wherein the acquisition module is specifically configured to: