面向DS/FH信号的循环平稳空时频测向算法  

Cyclostationary spatial time-frequency DOA estimation algorithm for DS/FH signal

作　　者：卢树军[1] 王世练[1] 朱江[1] 

机构地区：[1]国防科学技术大学电子科学与工程学院,湖南长沙410073

出　　处：《太赫兹科学与电子信息学报》2016年第5期695-700,共6页Journal of Terahertz Science and Electronic Information Technology

基　　金：航天支撑技术基金资助项目(基于空时频分析和压缩感知的空间谱估计测向定位高效算法研究);国家自然科学基金资助项目(61101097);武器装备预先研究基金资助项目(9140A25030113KG01359);抗干扰通信国家重点实验室基金资助项目(9140C0202011003)

摘　　要：综合采用直接序列扩频(DSSS)和跳频扩频(FHSS)体制的直序/跳频(DS/FH)通信信号显著降低了单位时频面积上的功率,经典的时频-多信号分类(TF-MUSIC)算法对这一类信号进行入射角(DOA)估计时误差较大。为解决该问题,本文对TF-MUSIC算法进行改进,在时频二维平面上计算DS/FH信号的时频特征值,并设计相应的时频掩膜滤波核函数,再根据估计出来的循环平稳频率计算相应的循环平稳空间自相关矩阵,得到了循环平稳可变核函数TF-MUSIC(CVCFTF-MUSIC)算法。该算法可显著提高DOA估计的精确度,数值仿真验证了上述观点。Direct Sequence/Frequency Hopping（DS/FH） signal composed by Direct Sequence Spread Spectrum（DSSS） and Frequency Hopping Spread Spectrum（FHSS） decreases the power density dramatically on time-frequency plane, and increases the estimation error of Direction-Of-Arrival（DOA） when classic TF-MUSIC（Time Frequency-Multiple Signal Classification） algorithm is applied in this circumstance. A novel scheme modified from classic TF-MUSIC algorithm is developed to resolve the problem. Firstly, the variable core function is designed on the parameters which character the DS/FH signal on time-frequency plane. Secondly, the cyclostationary frequency of DS/FH signal is estimated to construct the corresponding spatial covariance matrix. The modified algorithm is called Cyclostationary Variable Core Function TF-MUSIC（CVCFTF-MUSIC） algorithm. Simulation results validate that the proposed algorithm can increase the estimation precision of DOA estimation.

关 键 词：扩频/跳频信号 循环平稳分析 时频分析 入射角估计 

分 类 号：TN911.23[电子电信—通信与信息系统]