CN102148793A - Timing tracking processing method and device for OFDM (Orthogonal Frequency Division Multiplexing) system - Google Patents
Timing tracking processing method and device for OFDM (Orthogonal Frequency Division Multiplexing) system Download PDFInfo
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- CN102148793A CN102148793A CN2011100833473A CN201110083347A CN102148793A CN 102148793 A CN102148793 A CN 102148793A CN 2011100833473 A CN2011100833473 A CN 2011100833473A CN 201110083347 A CN201110083347 A CN 201110083347A CN 102148793 A CN102148793 A CN 102148793A
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Abstract
The embodiment of the invention provides a timing tracking processing method and device for an OFDM (Orthogonal Frequency Division Multiplexing) system. The method comprises the steps of carrying out FFT (Fast Fourier Transform) on received data through an FFT window to obtain a frequency domain signal; judging whether the quality of the frequency domain signal is higher than a threshold; maintaining the position of the FFT window if the quality of the frequency domain signal is not higher than the threshold; and adjusting the position of the FFT window if the quality of the frequency domain signal is higher than the threshold. By using the method and device provided by the embodiment of the invention, the position of the FFT window is adjusted and protected according to whether channel quality is good or not so that the timing tracking reliability of the OFDM system can be improved.
Description
Technical field
The present invention relates to communication technical field, relate in particular to a kind of timing tracking processing method and device of ofdm system.
Background technology
OFDM (Orthogonal Frequency Division Multiplexing, orthogonal frequency division multiplexi) is a kind of multi-subcarrier modulation system, overcomes the frequency selective fading of channel by the influence that reduces and eliminate intersymbol interference.Its basic principle is to be N subsignal with signal segmentation, modulates N mutually orthogonal subcarrier respectively with N subsignal then.Because the frequency spectrum of subcarrier is overlapped, thereby can obtain higher spectrum efficiency.In the last few years, OFDM has obtained using widely at wireless communication field, as at LTE (Long Term Evolution, Long Term Evolution (evolution technology of 3G)), LTE-A (LTE-Advanced, the follow-up evolution of LTE technology), be used among the WiMax (Worldwide Interoperability for MicrowaveAccess, promptly worldwide interoperability for microwave inserts).
Ofdm system is to regularly responsive, requires the UE (User Equipment, subscriber equipment) can the regularly variation of sync bit of real-time tracking, guarantees reliable performance, promptly according to receiving the original position that the adjustment of data synchronization testing result receives data.As shown in Figure 1, ofdm system is FFT (Fast Fourier Transform at receiving terminal, fast fourier transform) conversion, the original position of its FFT conversion promptly provides by regularly following the tracks of synchronously, sync bit should guarantee as far as possible that the position is from the beginning of no ISI (Inter-Symbol Interference, intersymbol interference) zone.
Existing regularly tracking technique is divided into the time domain timing estimation (as utilizing CP (Cyclic Prefix, Cyclic Prefix) estimate) and frequency domain timing estimation (obtaining channel footpath power-delay spectrum as utilizing channel estimation results), after obtaining estimated result, adjustment amount is fed back to the FFT processing module and adjust the FFT position of window, as shown in Figure 1 by a loop of regularly following the tracks of.The adjustment amount here can be the single results estimated, also can be that single is estimated through the result behind the time-domain filtering.Yet, because wireless environment is had relatively high expectations to the robustness of regularly following the tracks of.The reliability that current timing track loop is estimated for timing offset lacks protection, may cause regularly following the tracks of under some deep fade or low signal-to-noise ratio scene makeing mistakes.In case continuous mistake occurs, cause the position deviation of FFT window excessive probably, exceed the following range of regularly following the tracks of, even return to communication environment preferably like this, the position of FFT window also can't correct.
Summary of the invention
The embodiment of the invention provides a kind of timing tracking processing method and device of ofdm system, the reliability of following the tracks of with the timing that improves ofdm system.
The above-mentioned purpose of the embodiment of the invention is achieved by the following technical solution:
A kind of timing tracking processing method of orthogonal frequency division multiplex OFDM system, described method comprises:
By fast fourier transform FFT window, the data that receive are FFT obtain frequency-region signal;
Whether the quality of judging described frequency-region signal is higher than a thresholding;
If described frequency-region signal is of low quality in described thresholding, then keep described FFT position of window; If the quality of described frequency-region signal is higher than described thresholding, then adjust described FFT position of window.
A kind of timing tracking processing apparatus of orthogonal frequency division multiplex OFDM system, described device comprises:
Fast fourier transform FFT processing module is used for the window by FFT, the data that receive is FFT obtains frequency-region signal;
The protection judging module is used to judge whether the quality of described frequency-region signal is higher than a thresholding, if described frequency-region signal is of low quality in described thresholding, then sends the protection indication to adjusting the indication computing module; If the quality of described frequency-region signal is higher than described thresholding, then send the de-preservation indication to described adjustment indication computing module;
Described adjustment indication computing module is used for keeping described FFT position of window when receiving described protection indication; When receiving the indication of described de-preservation, impel described FFT processing module to adjust described FFT position of window.
Method and apparatus by the embodiment of the invention provides carries out the adjustment protection of FFT the window's position according to the channel quality quality, can improve the reliability of the timing tracking of ofdm system.
Description of drawings
Accompanying drawing described herein is used to provide further understanding of the present invention, constitutes the application's a part, does not constitute limitation of the invention.In the accompanying drawings:
Fig. 1 is the processing procedure schematic diagram that the timing of present ofdm system is followed the tracks of;
Fig. 2 is the timing tracking processing method flow chart of the ofdm system of the embodiment of the invention;
The processing procedure schematic diagram that the timing of the ofdm system of Fig. 3 after for the method for using present embodiment is followed the tracks of;
Fig. 4 is for determining the flow chart of an embodiment of channel quality quality according to frequency-region signal in embodiment illustrated in fig. 2;
Fig. 5 A is signal to noise ratio condition channel power delay spectrum schematic diagram of EVA channel under 10M bandwidth when better;
Channel power delay spectrum schematic diagram when Fig. 5 B is deep fade;
Fig. 6 is for determining the flow chart of the another one embodiment of channel quality quality according to frequency-region signal in embodiment illustrated in fig. 2;
Fig. 7 is for determining the flow chart of the another one embodiment of channel quality quality according to frequency-region signal in embodiment illustrated in fig. 2;
Fig. 8 is for determining the flow chart of the another one embodiment of channel quality quality according to frequency-region signal in embodiment illustrated in fig. 2;
Fig. 9 A is the timing tracking performance schematic diagram that EPA channel deep fade is not done to protect;
Fig. 9 B is the timing tracking performance schematic diagram that EPA channel deep fade is done protection;
Figure 10 is the composition frame chart of timing tracking processing apparatus of the ofdm system of the embodiment of the invention.
Embodiment
For the purpose, technical scheme and the advantage that make the embodiment of the invention is clearer,, the embodiment of the invention is described in further details below in conjunction with embodiment and accompanying drawing.At this, illustrative examples of the present invention and explanation thereof are used to explain the present invention, but not as a limitation of the invention.
The timing tracking processing method flow chart of a kind of ofdm system that Fig. 2 provides for the embodiment of the invention please refer to Fig. 2, and this method comprises:
Step 201:, the data that receive are FFT obtain frequency-region signal by fast fourier transform FFT window;
Wherein, FFT can realize that the FFT processing module can be a processor by the FFT processing module, is used for carrying out the FFT conversion to receiving data, export a frequency-region signal for regularly following the tracks of or demodulation, the original position of its FFT conversion can be adjusted according to the timing offset results estimated.
Step 202: whether the quality of judging described frequency-region signal is higher than a thresholding;
Wherein, whether the quality of judging described frequency-region signal is higher than a thresholding and just determines the channel quality quality according to this frequency-region signal.
Wherein, can obtain to reflect the parameter of channel communication quality according to the frequency-region signal of FFT processing module output, RSRP (Reference Signal Receiving Power for example, Reference Signal Received Power), RSRQ (Reference SignalReceived Quality, Reference Signal Received Quality), SINR (Signal to Interference plus Noise Ratio, Signal to Interference plus Noise Ratio), the peak-to-average force ratio of channel power delay spectrum, noise gate etc., by these parameters, can determine the channel quality quality, thereby identify the scene that deep fade or this class of low signal-to-noise ratio may cause the timing estimation mistake.
Step 203:, then keep described FFT position of window if described frequency-region signal is of low quality in described thresholding; If the quality of described frequency-region signal is higher than described thresholding, then adjust described FFT position of window.
Wherein,, illustrate that channel quality is relatively poor, then keep described FFT position of window if described frequency-region signal is of low quality in described thresholding.For example can send the protection indication, should adjust the indication computing module with forbidden energy to adjusting the indication computing module.At this moment, this adjusts the indication computing module according to this protection indication, and no longer the estimated result according to the timing offset estimation module calculates adjustment amount, thereby does not also feed back this adjustment amount to the FFT processing module, and the FFT processing module is not also carried out the adjustment of FFT position of window.Particularly, can calculate the adjustment amount of adjusting the FFT window, and utilize described adjustment amount to carry out the adjustment of FFT window.The process of calculating adjustment amount can adopt in the background technology the described method of Fig. 1 frequency-region signal to be carried out the estimation of timing offset, and according to described estimated result calculating adjustment amount, can certainly adopt other method of prior art, present embodiment is not done qualification to it.After obtaining adjustment amount, can also carry out filtering in the present embodiment, and adopt filtered adjustment amount that the FFT window is adjusted adjustment amount.
Wherein,, illustrate that channel quality is better, then adjust described FFT position of window if the quality of described frequency-region signal is higher than described thresholding.For example can send the de-preservation indication, to enable this adjustment indication computing module to adjusting the indication computing module.At this moment, this adjusts the indication computing module according to this de-preservation indication, removes the protection that timing is followed the tracks of, and this adjusts the indication computing module can calculate adjustment amount according to the timing offset results estimated, and feeds back to FFT processing module adjustment FFT position of window.
In the present embodiment, if channel quality is relatively poor, then owing to may cause the timing estimation mistake; therefore under relatively poor these scenes of channel quality; fixing regularly the tracking do not adjusted, and recovers the back de-preservation at communication condition, thereby improves the reliability of regularly following the tracks of.
The method that the embodiment of the invention provides can improve the reliability of regularly following the tracks of by ofdm system timing tracking results is protected.
The processing procedure schematic diagram that the timing of the ofdm system of Fig. 3 after for the method for using present embodiment is followed the tracks of please refer to Fig. 3, and in the processing procedure that the timing of present ofdm system is followed the tracks of, comprise: FFT processing module 31 is used for carrying out the FFT conversion to receiving data; Timing offset estimation module 32 is used for the data after the FFT conversion are carried out the estimation of timing offset, obtains estimated result; Adjust indication computing module 33, be used for calculating adjustment amount according to estimated result; Loop filter 34 is used for adjustment amount is carried out Filtering Processing and feeds back to the FFT processing module, so that the FFT processing module is adjusted the FFT position of window according to this adjustment amount.
Method according to present embodiment; in the processing procedure that the timing of present ofdm system is followed the tracks of; increased protection judging module 35; be used for determining the quality of channel quality according to the frequency-region signal of FFT processing module output; quality according to the channel quality of determining sends protection indication or de-preservation indication to adjusting indication computing module 33; do not calculate adjustment amount so that adjust indication computing module 33 according to this protection indication, perhaps calculate adjustment amount and feed back to FFT processing module 31 and adjust the FFT position of window according to this de-preservation indication.
In the present embodiment, this protection judging module 35 is used method embodiment illustrated in fig. 2, can improve the reliability of regularly following the tracks of by ofdm system timing tracking results is protected.
Fig. 4 be embodiment illustrated in fig. 1 in, judge whether the quality of described frequency-region signal is higher than described thresholding, also promptly determine the flow chart of an embodiment of channel quality quality according to frequency-region signal, please refer to Fig. 4, this flow process comprises:
Step 401:, measure the peak-to-average force ratio that obtains the channel power delay spectrum according to the frequency-region signal of FFT processing module output;
Step 402: peak-to-average force ratio and the predetermined peak-to-average force ratio threshold value that will measure the channel power delay spectrum that obtains compare;
Step 403: if the peak-to-average force ratio of described channel power delay spectrum is higher than described predetermined peak-to-average force ratio threshold value, determine that then the quality of described frequency-region signal is higher than described thresholding, illustrate that channel quality is better.
Wherein, be lower than this predetermined peak-to-average force ratio threshold value, then determine to illustrate that channel quality is relatively poor by the of low quality of described frequency-region signal in described thresholding if measure the peak-to-average force ratio of the channel power delay spectrum that obtains.
In the present embodiment, be to use based on the peak-to-average force ratio of channel estimating acquisition channel power delay spectrum to judge the channel quality quality.
In one embodiment, obtain the channel power delay spectrum, at first obtain the channel estimating frequency domain representation, that is:
Then, the zero padding of channel estimating frequency domain is realized N point IFFT (Inverse Fast Fourier Transform, invert fast fourier transformation) conversion, obtain channel impulse response and estimate (as follows).In order to improve estimated accuracy, can to after channel estimating windowing (as the Hamming window) filtering again zero padding be IFFT.
Wherein,
Represent n the sampling point that m OFDM symbol time domain channel estimated, n is the sampling point numbering.
Then, average N
AvThe channel impulse response of individual OFDM symbol estimates to obtain the power-delay spectrum:
Wherein, the difference of the shape of power-delay spectrum when signal to noise ratio is better and during deep fade is very big, is example with the LTE system, shown in Fig. 5 A and Fig. 5 B, Fig. 5 A is signal to noise ratio condition channel power delay spectrum of EVA channel under 10M bandwidth when better, the channel power delay spectrum when Fig. 5 B is deep fade.
In the present embodiment, definition peak-to-average force ratio PAR (Peak-to-Average Ratio) is the maximum of channel power delay spectrum
Mean value with whole delay spectrum
The ratio, that is:
In the present embodiment, a peak-to-average force ratio thresholding is set, promptly predetermined peak-to-average force ratio threshold value, when channel was in the deep fade state, peak value and average difference were little, PAR is lower, when this PAR is lower than the peak-to-average force ratio thresholding, think that channel quality is relatively poor, the result of timing estimation is unreliable, this does not adjust FFT the window's position, up to surpassing thresholding.
More than measuring the mode that obtains the channel power delay spectrum is an execution mode of the embodiment of the invention; present embodiment not with this as restriction, the frequency-region signal according to FFT processing module output in the prior art is measured the protection range that the method that obtains the channel power delay spectrum all is contained in the embodiment of the invention.
By the method for present embodiment, utilize the peak-to-average force ratio of estimated channel power-delay spectrum to carry out the protection that ofdm system is regularly followed the tracks of, can improve the reliability of regularly following the tracks of.
Fig. 6 be embodiment illustrated in fig. 1 in, judge whether the quality of described frequency-region signal is higher than described thresholding, also promptly determine the flow chart of the another one embodiment of channel quality quality according to frequency-region signal, please refer to Fig. 6, this flow process comprises:
Step 601:, measure the peak value that obtains the channel power delay spectrum according to the frequency-region signal of FFT processing module output;
Wherein, the mode that measure to obtain the peak value of channel power delay spectrum can adopt the mode identical with Fig. 4 embodiment, also can adopt other modes of the prior art, present embodiment not with this as restriction.
Step 602: the peak value and the predetermined peak value threshold value of described channel power delay spectrum are compared;
Wherein, present embodiment will be measured the product of the noise that obtains and pre-determined factor as the predetermined peak value threshold value, compare with the peak value of the channel power delay spectrum of measuring acquisition.
Step 603: if the peak value of described channel power delay spectrum is higher than described predetermined peak value threshold value, determine that then the quality of described frequency-region signal is higher than described thresholding, illustrate that channel quality is better.
Wherein,, then determine the of low quality of described frequency-region signal, illustrate that channel quality is relatively poor in described thresholding if the peak value of described channel power delay spectrum is lower than described predetermined peak value threshold value.
Wherein, present embodiment utilizes Noise Estimation to constitute thresholding and the timing of ofdm system is followed the tracks of is protected, and thinks that channel quality is relatively poor when the peak value of channel power delay spectrum during less than this thresholding, does not adjust; Think that communication condition recovers when the peak value of channel power delay spectrum during greater than this thresholding, channel quality is better, and this moment, de-preservation can carry out the adjustment of FFT the window's position.
By the method for present embodiment, utilize Noise Estimation to constitute thresholding the timing tracking of ofdm system is protected, can improve the reliability of regularly following the tracks of.
Fig. 7 be embodiment illustrated in fig. 1 in, judge whether the quality of described frequency-region signal is higher than described thresholding, also promptly determine the flow chart of the another one embodiment of channel quality quality according to frequency-region signal, please refer to Fig. 7, this flow process comprises:
Step 701:, measure and obtain Reference Signal Received Quality RSRQ value according to the frequency-region signal of FFT processing module output;
Wherein, measure acquisition RSRQ value by the frequency-region signal of FFT processing module output and can realize, do not repeat them here by the means of prior art.
Step 702: described RSRQ value and RSRQ threshold value are compared;
Step 703: if described RSRQ value is higher than described RSRQ threshold value, determine that then the quality of described frequency-region signal is higher than described thresholding, illustrate that channel quality is better.
Wherein,, then determine the of low quality of described frequency-region signal, illustrate that channel quality is relatively poor in described thresholding if described RSRQ value is lower than described RSRQ threshold value.
Wherein, present embodiment utilizes Reference Signal Received Quality RSRQ value that the timing of ofdm system is followed the tracks of and protects, and thinks that channel quality is relatively poor when measuring the RSRQ value that obtains less than predetermined RSRQ threshold value, does not adjust; Think that communication condition recovers when the RSRQ value during greater than predetermined RSRQ threshold value, channel quality is better, and this moment, de-preservation can carry out the adjustment of FFT the window's position.
By the method for present embodiment, utilize Reference Signal Received Quality RSRQ value that the timing of ofdm system is followed the tracks of and protect, can improve the reliability of regularly following the tracks of.
Fig. 8 be embodiment illustrated in fig. 1 in, judge whether the quality of described frequency-region signal is higher than described thresholding, also promptly determine the flow chart of the another one embodiment of channel quality quality according to frequency-region signal, please refer to Fig. 8, this flow process comprises:
Step 801:, measure picked up signal and interference plus noise than the SINR value according to the frequency-region signal of FFT processing module output;
Wherein, measure acquisition SINR value by the frequency-region signal of FFT processing module output and can realize, do not repeat them here by the means of prior art.
Step 802: described SINR value and SINR threshold value are compared;
Step 803: if described SINR value is higher than described SINR threshold value, determine that then the quality of described frequency-region signal is higher than described thresholding, illustrate that channel quality is better.
Wherein,, then determine the of low quality of described frequency-region signal, illustrate that channel quality is relatively poor in described thresholding if described SINR value is lower than described SINR threshold value.
Wherein, present embodiment utilizes Signal to Interference plus Noise Ratio SINR value that the timing of ofdm system is followed the tracks of and protects, and thinks that channel quality is relatively poor when measuring the SINR value that obtains less than predetermined SINR threshold value, does not adjust; Think that communication condition recovers when the SINR value during greater than predetermined SINR threshold value, channel quality is better, and this moment, de-preservation can carry out the adjustment of FFT the window's position.
By the method for present embodiment, utilize Signal to Interference plus Noise Ratio SINR value that the timing of ofdm system is followed the tracks of and protect, can improve the reliability of regularly following the tracks of.
Fig. 9 A is EPA (Extended Pedestrian A model; expansion walking channel model A) the channel deep fade timing tracking performance schematic diagram not doing to protect; Fig. 9 B is a timing tracking performance schematic diagram of doing protection according to the method for present embodiment; the Ts of Y-axis unit (32.55ns) wherein; input signal does not have timing offset, and promptly desirable timing estimation results should be 0.As seen do not do protection and will cause regularly adjusting mistake,, can not recover correct timing even recover signal to noise ratio when the mistake adjustment surpasses regularly track algorithm effective range.Done the protection back and regularly can remain on original adjustment position, can after the channel signal to noise ratio is recovered, can also not continue current timing working according to wrong estimated result adjustment.
The composition frame chart of the timing tracking processing apparatus of a kind of orthogonal frequency division multiplex OFDM system that Figure 10 provides for the embodiment of the invention please refer to Figure 10, and this device comprises:
Fast fourier transform FFT processing module 101 is used for the window by FFT, the data that receive is FFT obtains frequency-region signal; This FFT processing module 101 can be a processor;
Adjust indication computing module 103, be used for when receiving described protection indication, keeping described FFT position of window; When receiving the indication of described de-preservation, impel described FFT processing module 101 to adjust described FFT position of window.Particularly, this adjustment indication computing module 103 can calculate an adjustment amount and send to FFT processing module 101, makes FFT processing module 101 can utilize described adjustment amount to carry out the adjustment of FFT window.The process of calculating adjustment amount can adopt the described method of Fig. 1 in the background technology, also can adopt other method of prior art, and present embodiment is not done qualification to it.Described adjustment indication computing module 103 can be a calculator.
In one embodiment, protection judging module 102 comprises:
First measurement module is used for according to described frequency-region signal, measures the peak-to-average force ratio that obtains the channel power delay spectrum; This module can be a meter;
First comparison module is used for the peak-to-average force ratio and the predetermined peak-to-average force ratio threshold value of described channel power delay spectrum are compared; This module can be a comparator;
First determination module when being used for peak-to-average force ratio at described channel power delay spectrum and being higher than described predetermined peak-to-average force ratio threshold value, determines that the quality of described frequency-region signal is higher than described thresholding, illustrates that channel quality is better.And when being used for peak-to-average force ratio at described channel power delay spectrum and being lower than described predetermined peak-to-average force ratio threshold value, determine the of low quality of described frequency-region signal in described thresholding, illustrate that channel quality is relatively poor.
In another embodiment, protection judging module 102 comprises:
Second measurement module is used for according to described frequency-region signal, measures the peak value that obtains the channel power delay spectrum; This module can be a meter;
Second comparison module is used for the peak value and the predetermined peak value threshold value of described channel power delay spectrum are compared; This module can be a comparator;
Second determination module when being used for peak value at described channel power delay spectrum and being higher than described predetermined peak value threshold value, determines that the quality of described frequency-region signal is higher than described thresholding, illustrates that channel quality is better.And when being used for peak value at described channel power delay spectrum and being lower than described predetermined peak value threshold value, determine the of low quality of described frequency-region signal in described thresholding, illustrate that channel quality is relatively poor;
In another embodiment, protection judging module 102 comprises:
The 3rd measurement module is used for according to described frequency-region signal, measures to obtain Reference Signal Received Quality RSRQ value; This module can be a meter;
The 3rd comparison module is used for described RSRQ value and RSRQ threshold value are compared; This module can be a comparator;
The 3rd determination module is used for determining that the quality of described frequency-region signal is higher than described thresholding when described RSRQ value is higher than described RSRQ threshold value, illustrates that channel quality is better.And be used for when described RSRQ value is lower than described RSRQ threshold value, determining the of low quality in described thresholding of described frequency-region signal, illustrate that channel quality is relatively poor.
In another embodiment, protection judging module 102 comprises:
The 4th measurement module is used for according to described frequency-region signal, measures picked up signal and interference plus noise than the SINR value; This module can be a meter;
The 4th comparison module is used for described SINR value and SINR threshold value are compared; This module can be a comparator;
The 4th determination module is used for determining that the quality of described frequency-region signal is higher than described thresholding when described SINR value is higher than described SINR threshold value, illustrates that channel quality is better.And be used for when described SINR value is lower than described SINR threshold value, determining the of low quality in described thresholding of described frequency-region signal, illustrate that channel quality is relatively poor.
Each part of the device of present embodiment is respectively applied for each step that realizes method embodiment illustrated in fig. 2, owing in embodiment illustrated in fig. 2, each step is had been described in detail, does not repeat them here.
In one embodiment, this device also comprises:
Timing offset estimation module 104 is used for carrying out according to described frequency-region signal the estimation of timing offset, obtains estimated result; This module can be another processor;
Described adjustment indication computing module 103 is when receiving described de-preservation indication; be used for calculating adjustment amount and providing this adjustment amount, adjust described FFT position of window according to described adjustment amount to impel described FFT processing module 101 to described FFT processing module 101 according to described estimated result.
In one embodiment, this device also comprises:
By the device of present embodiment, can protect ofdm system timing tracking results, can improve the reliability that ofdm system is regularly followed the tracks of thus.
The method of describing in conjunction with embodiment disclosed herein or the step of algorithm can directly use the software module of hardware, processor execution, and perhaps the combination of the two is implemented.Software module can place the storage medium of any other form known in random asccess memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable ROM, register, hard disk, moveable magnetic disc, CD-ROM or the technical field.
Above-described specific embodiment; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the above only is specific embodiments of the invention; and be not intended to limit the scope of the invention; within the spirit and principles in the present invention all, any modification of being made, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (12)
1. the timing tracking processing method of an orthogonal frequency division multiplex OFDM system is characterized in that, described method comprises:
By fast fourier transform FFT window, the data that receive are FFT obtain frequency-region signal;
Whether the quality of judging described frequency-region signal is higher than a thresholding;
If described frequency-region signal is of low quality in described thresholding, then keep described FFT position of window; If the quality of described frequency-region signal is higher than described thresholding, then adjust described FFT position of window.
2. method according to claim 1 is characterized in that, whether the described quality of judging described frequency-region signal is higher than described thresholding comprises:
According to described frequency-region signal, measure the peak-to-average force ratio that obtains the channel power delay spectrum;
The peak-to-average force ratio and the predetermined peak-to-average force ratio threshold value of described channel power delay spectrum are compared;
If the peak-to-average force ratio of described channel power delay spectrum is higher than described predetermined peak-to-average force ratio threshold value, determine that then the quality of described frequency-region signal is higher than described thresholding.
3. method according to claim 1 is characterized in that, whether the described quality of judging described frequency-region signal is higher than described thresholding comprises:
According to described frequency-region signal, measure the peak value that obtains the channel power delay spectrum;
The peak value and the predetermined peak value threshold value of described channel power delay spectrum are compared;
If the peak value of described channel power delay spectrum is higher than described predetermined peak value threshold value, determine that then the quality of described frequency-region signal is higher than described thresholding.
4. method according to claim 1 is characterized in that, whether the described quality of judging described frequency-region signal is higher than described thresholding comprises:
According to described frequency-region signal, measure and obtain Reference Signal Received Quality RSRQ value;
Described RSRQ value and RSRQ threshold value are compared;
If described RSRQ value is higher than described RSRQ threshold value, determine that then the quality of described frequency-region signal is higher than described thresholding.
5. method according to claim 1 is characterized in that, whether the described quality of judging described frequency-region signal is higher than described thresholding comprises:
According to described frequency-region signal, measure picked up signal and interference plus noise than the SINR value;
Described SINR value and SINR threshold value are compared;
If described SINR value is higher than described SINR threshold value, determine that then the quality of described frequency-region signal is higher than described thresholding.
6. the timing tracking processing apparatus of an orthogonal frequency division multiplex OFDM system is characterized in that, described device comprises:
Fast fourier transform FFT processing module is used for the window by FFT, the data that receive is FFT obtains frequency-region signal;
The protection judging module is used to judge whether the quality of described frequency-region signal is higher than a thresholding, if described frequency-region signal is of low quality in described thresholding, then sends the protection indication to adjusting the indication computing module; If the quality of described frequency-region signal is higher than described thresholding, then send the de-preservation indication to described adjustment indication computing module;
Described adjustment indication computing module is used for keeping described FFT position of window when receiving described protection indication; When receiving the indication of described de-preservation, impel described FFT processing module to adjust described FFT position of window.
7. device according to claim 6 is characterized in that, described protection judging module comprises:
First measurement module is used for according to described frequency-region signal, measures the peak-to-average force ratio that obtains the channel power delay spectrum;
First comparison module is used for the peak-to-average force ratio and the predetermined peak-to-average force ratio threshold value of described channel power delay spectrum are compared;
First determination module when being used for peak-to-average force ratio at described channel power delay spectrum and being higher than described predetermined peak-to-average force ratio threshold value, determines that the quality of described frequency-region signal is higher than described thresholding.
8. device according to claim 6 is characterized in that, described protection judging module comprises:
Second measurement module is used for according to described frequency-region signal, measures the peak value that obtains the channel power delay spectrum;
Second comparison module is used for the peak value and the predetermined peak value threshold value of described channel power delay spectrum are compared;
Second determination module when being used for peak value at described channel power delay spectrum and being higher than described predetermined peak value threshold value, determines that the quality of described frequency-region signal is higher than described thresholding.
9. device according to claim 6 is characterized in that, described protection judging module comprises:
The 3rd measurement module is used for according to described frequency-region signal, measures to obtain Reference Signal Received Quality RSRQ value;
The 3rd comparison module is used for described RSRQ value and RSRQ threshold value are compared;
The 3rd determination module is used for determining that the quality of described frequency-region signal is higher than described thresholding when described RSRQ value is higher than described RSRQ threshold value.
10. device according to claim 6 is characterized in that, described protection judging module comprises:
The 4th measurement module is used for according to described frequency-region signal, measures picked up signal and interference plus noise than the SINR value;
The 4th comparison module is used for described SINR value and SINR threshold value are compared;
The 4th determination module is used for determining that the quality of described frequency-region signal is higher than described thresholding when described SINR value is higher than described SINR threshold value.
11., it is characterized in that described device also comprises according to the arbitrary described device of claim 6-10:
The timing offset estimation module is used for carrying out according to described frequency-region signal the estimation of timing offset, obtains estimated result;
Described adjustment indication computing module is when receiving described de-preservation indication; be used for calculating adjustment amount and providing this adjustment amount, adjust described FFT position of window according to described adjustment amount to impel described FFT processing module to described FFT processing module according to described estimated result.
12. device according to claim 11 is characterized in that, described device also comprises:
Loop filter is coupled respectively with described adjustment indication computing module and described FFT processing module, is used for the adjustment amount that described adjustment indication computing module calculates is carried out filtering and filtered adjustment amount is fed back to described FFT processing module.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104467938A (en) * | 2014-11-20 | 2015-03-25 | 京信通信系统（中国）有限公司 | Method and system for selecting diversity reception merging mode |
| CN104518999A (en) * | 2013-09-29 | 2015-04-15 | 重庆重邮信科通信技术有限公司 | Method and system for determining received power of reference signal, and mobile terminal |
| CN107852632A (en) * | 2015-07-22 | 2018-03-27 | 夏普株式会社 | Terminal installation, base station apparatus, measuring method and integrated circuit |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1816032A (en) * | 2005-02-04 | 2006-08-09 | 三星电子株式会社 | Apparatus and method for compensating for a frequency offset in a wireless communication system |
| EP1267535B1 (en) * | 2001-06-11 | 2007-04-11 | SAMSUNG ELECTRONICS Co. Ltd. | Method and apparatus for symbol synchronisation in a multicarrier receiver |
| CN101043503A (en) * | 2007-04-17 | 2007-09-26 | 华为技术有限公司 | Method for fine synchronizing OFDM symbol and apparatus thereof |
| CN101068232A (en) * | 2007-06-12 | 2007-11-07 | 华为技术有限公司 | Method and device for getting channel time domain response, OFDM fine symbol synchronizing method and device |
| US20070280364A1 (en) * | 2006-05-31 | 2007-12-06 | Fujitsu Limited | Ofdm receiver, interference wave discernment method, window control apparatus and window control method |
-
2011
- 2011-04-02 CN CN2011100833473A patent/CN102148793A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1267535B1 (en) * | 2001-06-11 | 2007-04-11 | SAMSUNG ELECTRONICS Co. Ltd. | Method and apparatus for symbol synchronisation in a multicarrier receiver |
| CN1816032A (en) * | 2005-02-04 | 2006-08-09 | 三星电子株式会社 | Apparatus and method for compensating for a frequency offset in a wireless communication system |
| US20070280364A1 (en) * | 2006-05-31 | 2007-12-06 | Fujitsu Limited | Ofdm receiver, interference wave discernment method, window control apparatus and window control method |
| CN101043503A (en) * | 2007-04-17 | 2007-09-26 | 华为技术有限公司 | Method for fine synchronizing OFDM symbol and apparatus thereof |
| CN101068232A (en) * | 2007-06-12 | 2007-11-07 | 华为技术有限公司 | Method and device for getting channel time domain response, OFDM fine symbol synchronizing method and device |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104518999A (en) * | 2013-09-29 | 2015-04-15 | 重庆重邮信科通信技术有限公司 | Method and system for determining received power of reference signal, and mobile terminal |
| CN104518999B (en) * | 2013-09-29 | 2019-03-12 | 锐迪科（重庆）微电子科技有限公司 | Determine the method, system and mobile terminal of Reference Signal Received Power |
| CN104467938A (en) * | 2014-11-20 | 2015-03-25 | 京信通信系统（中国）有限公司 | Method and system for selecting diversity reception merging mode |
| CN104467938B (en) * | 2014-11-20 | 2018-06-22 | 京信通信系统（中国）有限公司 | Selection diversity receives the method and system of merging patterns |
| CN107852632A (en) * | 2015-07-22 | 2018-03-27 | 夏普株式会社 | Terminal installation, base station apparatus, measuring method and integrated circuit |
| CN107852632B (en) * | 2015-07-22 | 2022-07-26 | Oppo广东移动通信有限公司 | Terminal device, base station device, measurement method, and integrated circuit |
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