Parallel acquisition algorithm in time-frequency domain
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摘要: 针对DS/FH(Direct Sequence/Frequency Hopping)混合扩频测控信号的快速捕获,经典的时域并行方法或频域并行方法已不能满足需求.为了进一步提高载波捕获精度,在PMF-FFT(Partial Match Filter-Fast Fourier Transform)算法基础上,提出了一种反馈式结构的时频域并行捕获算法,通过PMF-FFT算法粗估载波频偏,利用一种Quinn频率插值算法提高频偏估计精度,并使用估计结果调整本地载波,再次进行捕获.理论分析和仿真结果表明,该算法与PMF-FFT算法相比,提高了载波捕获精度,在大频偏低信噪比条件下增加了频率分析带宽、减少了平均捕获时间.Abstract: Due to the fact that the classic method of parallel acquisition in the time or frequency domain cannot satisfy the demand of the fast acquisition of the direct sequence/frequency hopping(DS/FH) hybrid spread spectrum signal in TT&C. In order to further improve the acquisition accuracy of the carrier, on the basis of the partial match filter-fast fourier transform(PMF-FFT) algorithm, a parallel algorithm in the time-frequency domain with feedback architecture was proposed. Through the coarse estimation of the carrier frequency offset by the PMF-FFT algorithm, the new algorithm uses the Quinn frequency interpolation algorithm to improve the estimation accuracy of frequency offset, modifying the local carrier by employing the estimated result and reacquiring. Theoretical analysis and simulation results show that, compared to the PMF-FFT algorithm, the new method improves acquisition accuracy of the carrier, under the conditions of large frequency offset and low SNR, increases the frequency analysis bandwidth, and reduces the average acquisition time.
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[1] Liu Chang,Zhang Jun.Analysis and optimization of PMF-FFT acquisition algorithm for high-dynamic GPS signal[C] //2011 IEEE 5th International Conference on Cybernetics and Intelligent Systems.Qingdao:IEEE,2011:185-189 [2] Qi Hua,Shi Xiaoqian,Ji Le.PMF-FFT algorithm for PN code acquisition[J].Journal of Xi'an Technological University,2010,30(1):57-61 [3] 章兰英,袁嗣杰,陈源.航天扩频测控系统中伪码捕获方法研究[J].电子学报,2011,39(6):1471-1476
Zhang Lanying,Yuan Sijie,Chen Yuan.Research on pseu-do code acquisition method in aerospace spread spectrum TT&C system[J].Chinese Journal of Electronics,2011,39(6):1471-1476(in Chinese)[4] Thomas Grandke.Interpolation algorithms for discrete Fourier transforms of weighted signals[J].IEEE Transactions on Instrumentation and Measurement,1983,32(2):350-355 [5] Quinn B G.Estimating frequency by interpolation using Fourier coefficient[J].IEEE Trans on Signal Processing,1994,42(5):1264-1268 [6] 曹延伟,张昆帆,江志红,等.一种稳健的离散频谱校正方法[J].电子与信息学报,2005,27(9):1353-1356
Cao Yanwei,Zhang Kunfan,Jiang Zhihong,et al.A robust discrete spectrum correcting method[J].Journal of Electronics & Information Technology,2005,27(9):1353-1356(in Chinese)[7] Aboutanios E.A modified dichotomous search frequency estimator[J].IEEE Signal Processing Letters,2004,11(2):186-188 [8] Aboutanios E,Mulgrew B.Iterative frequency estimation by interpolation on Fourier coefficients[J].IEEE Trans on Signal Processing,2005,53(4):1237-1242 [9] Quinn B G.Estimation of frequency,amplitude,and phase from the DFT of a time series[J].IEEE Trans on Signal Processing,1997,45(3):814-817 [10] 齐国清.几种基于FFT的频率估计方法精度分析[J].振动工程学报,2006,19(1):86-92
Qi Guoqing.Precision analysis of several FFT-based frequency estimation methods[J].Journal of Vibration Engineering,2006,19(1):86-92(in Chinese) -
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