摘要
在通信测控系统中短的信号捕获时间是非常重要的。提出了一种基于快速傅里叶变换(FFT)的多谱勒直接序列扩频信号的快速捕获方法,利用频域循环移位特性和FFT变换特点计算出本地伪码序列与输入信号序列的相位差,检测出输入信号多普勒频移。从理论上对该技术进行了研究,分析了捕获方法的基本原理,推导了二维相关计算的数学表达式。用Matlab/Simulink工具进行了仿真,检测出多谱勒频移和伪码相位,进一步验证了该算法捕获的正确性。
The short acquisition time is very important for TTC.This paper describes a fast acquisition algorithm for Doppler direct sequence spread spectrum signals based on fast Fourier transform（ FFT）.This algorithm uses frequency domain cyclic shift theorem and FFT transform to calculate the phase difference of local PN-code sequences and incoming sequence and estimate the Doppler shifts.This paper analyzes the basic principles of the fast acquisition algorithm and deduces the mathematical expressions of two-dimensional correlation calculation.The simulation is performed with MATLAB / Simulink tools to detect Doppler shifts and PN-cod phase,and the results show that the mathematical expressions of this algorithm are correct.
出处
《无线电工程》
2016年第1期39-41,共3页
Radio Engineering
基金
国家部委基金资助项目
