Journal of South China University of Technology(Natural Science Edition) ›› 2025, Vol. 53 ›› Issue (1): 84-91.doi: 10.12141/j.issn.1000-565X.230574

• Electronics, Communication & Automation Technology • Previous Articles     Next Articles

A Design Method of Sparse FIR Filter Based on Weighted Least Squares

ZHUANG Ling1,2, SONG Shiwei1, LIU Ying1   

  1. 1.School of Communication and Information Engineering,Chongqing University of Posts and Telecommunications,Chongqing 400065,China
    2.Chongqing Key Laboratory of Mobile Communications Technology,Chongqing 400065,China
  • Received:2023-09-11 Online:2025-01-25 Published:2025-01-02
  • About author:庄陵(1978—),女,博士,副教授,主要从事滤波器组调制技术、多载波通信及信号处理研究。E-mail: zhuang-ling@cqupt.edu.cn
  • Supported by:
    the Science and Technology Research Program of Chongqing Municipal Education Commission(KJQN202200617)

Abstract:

The development of large-scale communication systems puts higher requirements on traditional filter design. Sparse finite impulse response (FIR) filters have the characteristics of low computational complexity and low implementation cost, but conventional convex relaxation approximation design methods produce additional approximation errors, exhibit suboptimal sparsity, and involve complex solving processes. To address the issue of high implementation costs caused by the large number of multipliers in FIR filter design, this paper proposed a sparse FIR filter design method based on a weighted least squares criterion. Firstly, the norm of the initial sparse representation is replaced based on the properties of different norms, thereby improving the objective function. This modification maintains sparsity while addressing the challenge of directly solving non-convex functions. Next, the target problem was reformulated as the difference between two convex sub-problems. Simplified sub-problems were constructed according to iterative rules, and an alternating solution method was adopted to further enhance solving efficiency and reduce complexity. Finally, after determining the positions of zero coefficients, a weighted least squares problem was solved to further reduce approximation errors. The simulation results show that compared with the existing sparse filter solving methods, the proposed method can improve the coefficient sparsity performance of FIR filters, reduce the number of multipliers and obtain a compromise between root-mean-square error and maximum error in the case of sparsity enhancement. Meanwhile, the computational solving time is significantly reduced, and solving efficiency is notably improved.

Key words: filter, design method, finite impulse response, weighted least squares

CLC Number: