CAJ | 학술논문

针对传统方法对高动态大多普勒信号捕获存在的困难，本文提出的基于 FFT 的捕获方法，充分考虑了高动态性的影响，改进了接收信号模型，引入了多普勒频率变化率。算法将传统的二维搜索化为了先捕获多普勒频偏及频率变化率，再捕获伪码延时的二步搜索。频偏估计方面分析了匹配傅里叶变换法和延时自相关 FFT 估计法，码相位估计方面分析了伪码循环相关捕获法，并对两个阶段各个方案的复杂度、抗噪声性能进行了分析和改进，降低了算法复杂度、提高了抗噪声性能，最后用 MATLAB 仿真验证了方法的正确性和有效性。
침대전통방법대고동태대다보륵신호포획존재적곤난，본문제출적기우 FFT 적포획방법，충분고필료고동태성적영향，개진료접수신호모형，인입료다보륵빈솔변화솔。산법장전통적이유수색화위료선포획다보륵빈편급빈솔변화솔，재포획위마연시적이보수색。빈편고계방면분석료필배부리협변환법화연시자상관 FFT 고계법，마상위고계방면분석료위마순배상관포획법，병대량개계단각개방안적복잡도、항조성성능진행료분석화개진，강저료산법복잡도、제고료항조성성능，최후용 MATLAB 방진험증료방법적정학성화유효성。
Traditional PN code acquisition algorithm is effectless for high dynamic Doppler shift signals.This paper presents acquisition methods based on FFT .It considers Doppler frequency change rate in high dynamic environment and improves the model of the received signal.It divides traditional two-dimensional search algorithm into the separate estimation of Doppler frequency offset and frequency change rate as well as pseudo-code phase.The complexity and signal-to-noise ratio of Doppler frequency shift estimation method,Matching Fourier Transform and Delay Self-correlation,and code phase circular correlation estimation method are analysed and improved.The simulation by using MATLAB verifies that the algorithm is correct and effective.