摘要
针对低轨卫星信号分布式中时差和多普勒频差联合估计的问题,提出一种基于改进小波阈值的时差频差联合估计算法。该方法在利用二阶互模糊函数进行时差和多普勒频差联合估计的基础上,引入小波变换,选择合适的阈值函数和自适应阈值,从而对两路接收信号进行去噪,提高联合估计的性能。仿真结果表明,在低信噪比环境下,基于改进小波阈值的时差频差联合估计法抑制了噪声的影响,提高了联合估计的精度。
Aiming at the problem of joint estimation of TDOA and Doppler frequency difference in low earth orbit satellite signal distribution,a joint estimation algorithm of Time Difference of Arrival(TDOA)and frequency difference based on improved wavelet threshold is proposed in this paper.Based on the joint estimation of TDOA and Doppler frequency difference by using the secondorder cross ambiguity function,the method introduces wavelet transform and selects the appropriate threshold function and adaptive threshold,so as to denoise the two received signals and improve the performance of joint estimation.The simulation results show that in the environment of low signal-to-noise ratio,the TDOA frequency difference joint estimation method based on improved wavelet threshold suppresses the influence of noise and improves the accuracy of joint estimation.
作者
徐菁
倪淑燕
XU Jing;NI Shuyan(Graduate School,Space Engineering University,Beijing 101400,China;Department of Electronic and Optical Engineering,Space Engineering University,Beijing 101400,China)
出处
《电声技术》
2022年第8期112-117,共6页
Audio Engineering
关键词
阈值函数
阈值去噪
二阶互模糊
联合估计
threshold function
threshold denoising
second order mutual ambiguity
joint estimation
