Joint Blind Estimation of PN Codes and Channels with Maximum Likelihood for DSSS Signals in Multipath Channels

被引:0
|
作者
Liu Q.-H. [1 ]
Xu M.-K. [1 ]
Li T.-Y. [1 ]
机构
[1] Information Engineering University, Zhengzhou
来源
关键词
DSSS; Iterative least square projection (ILSP); Maximum likelihood; Multipath channels; PN codes; Total least squares;
D O I
10.12263/DZXB.20200024
中图分类号
学科分类号
摘要
To solve the problem of pseudorandom (PN) codes estimation for direct sequence spread spectrum (DSSS) signals over multipath channels in non-cooperative communication, based on analyzing the second-order statistics of the signals, a method for joint blind estimation of PN codes and channels with maximum likelihood (ML) is proposed. First, we establish a ML mathematical model of PN codes and multipath channels. Then, we iteratively transform the mathematical model and use the iterative least square projection (ILSP) algorithm to estimate the PN code and channel. Furthermore, to reduce the complexity of the algorithm and avoid the matrix inversion, we present an adaptive rule of our algorithm. Finally, to avoid the decrease of PN code estimation accuracy caused by the channel estimation error, especially under low signal-to-noise ratio, an improved algorithm based on the iterative total least squares projection (ITLSP) is presented. The proposed methods are applicable to all types of PN codes and the simulation results are presented to demonstrate the effectiveness of the algorithms. © 2021, Chinese Institute of Electronics. All right reserved.
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页码:1480 / 1488
页数:8
相关论文
共 21 条
  • [1] Burel G, Bouder C., Blind estimation of the pseudo-random sequence of a direct sequence spread spectrum signal, David Streight Milcom 2000 21st Century Military Communications Conference Proceedings, pp. 967-970, (2000)
  • [2] Zhang H B, Lv M., Blind estimation of PN spreading sequence based on subspace tracking, Systems Engineering and Electronics, 28, 10, pp. 1470-1472, (2006)
  • [3] Zhang T Q, Lin X K, Zhou Z Z., A neural network approach to blind-estimation of PN spreading sequence in lower SNR DS/SS signals, Journal of Circuits and Systems, 12, 2, pp. 118-123, (2007)
  • [4] Wei Y P, Liu L K, Guo H, Et al., Approach to blind estimation of pseudo random code sequence for DSSS signal in multipath, Computer Engineering and Applications, 49, 12, pp. 195-199, (2013)
  • [5] Shen L, Li S J, Wang Y B, Et al., Blind estimation of pseudo-random sequences of spread spectrum signals in multi-paths, Journal of Zhejiang University (Engineering Science), 41, 11, pp. 1828-1833, (2007)
  • [6] Yang Y J, Wu C H, Tao L., Triple correlation analysis for m sequence estimation, The Journal of Electronic Defense, 20, 6, pp. 18-21, (2005)
  • [7] Fu W H, Yang X N, Liu N A., The multi-user detection and chip sequence estimation for CDMA system based on the blind source separation, Acta Electronica Sinica, 36, 7, pp. 1319-1323, (2008)
  • [8] Tsatsanis M K, Giannakis G B., Blind estimation of direct sequence spread spectrum signals in multipath, IEEE Transactions on Signal Processing, 45, 5, pp. 1241-1252, (1997)
  • [9] Moulines E, Duhamel P, Cardoso J F, Et al., Subspace methods for the blind identification of multichannel FIR filters, IEEE Transactions on Signal Processing, 43, 2, pp. 516-525, (1995)
  • [10] Chen E Y, Yuan J H, Miao F, Et al., Multi-user multi-path DS-CDMA signal pseudo-code blind estimation based on Givens rotation, Journal of Anhui University (Natural Science Edition), 41, 1, pp. 67-72, (2017)