弹载并行组合扩频载波快速精确估计方法  

Fast and accurate estimation method of missile-borne parallel combined spread spectrum carrier

作　　者：王志强 丁丹 杨柳 WANG Zhiqiang;DING Dan;YANG Liu(Department of Electrical and Optical Engineering,Space Engineering University,Beijing 101416,China)

机构地区：[1]航天工程大学电子与光学工程系,北京101416

出　　处：《兵器装备工程学报》2022年第S02期91-94,126,共5页Journal of Ordnance Equipment Engineering

摘　　要：针对低信噪比、高动态条件下火箭弹数据链并行组合扩频载波同步性差的问题,设计“非平衡QPSK+并行组合扩频”的弹载数据传输体制,提出基于软判决二分迭代最大化的并行组合扩频载波精估计方法:首先对Q路同步头进行傅里叶变换,完成载波频偏粗估计,利用该粗估计结果对I路进行初补偿,进而通过二分迭代法搜寻频偏精估计值,使得I路并行组合扩频软判决值最大化。仿真结果表明:该算法估计方差比传统方法更接近克拉美罗界;并且信噪比门限达-3 dB,适用于低信噪比环境。Aiming at the low signal-to-noise ratio and high dynamic conditions of a poor synchronization of rocket data link parallel combined spread spectrum carrier,an“unbalanced QPSK+parallel combination spread spectrum”missile-borne data transmission system is designed,and a parallel combination based on soft-decision bipartite iterative maximization is proposed.Spread spectrum carrier fine estimation method,is then designed to perform Fourier transform on the Q-channel synchronization head to complete the rough estimation of the carrier frequency offset,use the rough estimation result to perform initial compensation for the I channel,and then search for the frequency offset fine estimation value by the binary iteration method to maximize the soft-decision value of I-channel parallel combination spread spectrum.The simulation results show that the estimated variance of the algorithm is closer to the Cramero bound than the traditional method,and the SNR threshold reaches-3 dB,which is suitable for the low SNR environment.

关 键 词：高动态 并行组合扩频 频偏估计 二分迭代 克拉美罗界 

分 类 号：TJ71[兵器科学与技术—武器系统与运用工程]