采用随机共振增强的混合扩频信号跳频参数估计  

An Estimation Method of Frequency Hopping Parameters for Hybrid Spread Spectrum Signals Using Stochastic Resonance Enhanced Strategy

作　　者：尚佳栋[1] 王祖林[1] 周丽娜[1] 裴睿淋 

机构地区：[1]北京航空航天大学电子信息工程学院,北京100191

出　　处：《西安交通大学学报》2014年第10期42-48,共7页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(61071070);教育部高等学校博士学科点专项科研基金资助项目(20091102120010)

摘　　要：为解决强背景噪声下直扩/跳频(DS/FH)混合扩频信号的跳频参数估计精度低的问题,提出了一种基于随机共振的参数估计(SRPE)方法。首先对非线性预处理后的DS/FH信号进行信道化调制,将其转化为多个低频单分量信号,以满足随机共振的绝热近似条件;然后根据噪声强度自适应调整系统的参数,对每个单分量信号进行随机共振处理,使目标信号得到增强;最后采用Wigner-Villa变换来估计信号的跳频频率和跳速。仿真结果表明:SRPE方法能够提高目标信号的信噪比,实现强背景噪声下对DS/FH跳频参数的精确估计;在-10dB的低输入信噪比下,SRPE方法的频率估计误差低于10-3,与信道化谱增强方法相比,估计精度提高了70%以上。An novel parameter estimation （SRPE） method based on stochastic resonance （SR） is proposed to solve the problem that the frequency hopping parameter estimation of hybrid discrete sequence and frequency hopping （DS/FH） signals is of low accuracy under strong noise environment. First, A channelized modulator is used to decompose the DS/FH reference signal into single-component signals so that the adiabatic approximation condition of SR is satisfied. Then, the SR is used to increase the signal-to-noise ratio （SNR）, and the frequency hopping parameters of the DS/FH are estimated by using the Wigner-Villa transform. Simulations of the SRPE method show that the root-mean-squared error of hopping frequency estimation is lower than 10-3 when SNR is lower than --10 dB, and a comparison with the channelized spectrum enhancement （CSE） method shows that the parameter estimation accuracy of the SRPE method is increased by 70 %.

关 键 词：扩频信号 参数估计 随机共振 Wigner—Villa变换 

分 类 号：TN911.7[电子电信—通信与信息系统]