摘要
Abstract
In signal processing of the multifunctional digital baseband,the orthogonal code division multiple access(CDMA)causes relatively severe interference,which prevents the traditional FFT(fast Fourier transform)algorithm from figuring out carrier frequency acquisition.In this paper,the influence of spreading code in orthogonal channels on FFT algorithm is analyzed theoretically and simulated.Then,two methods,named bidirectional searching capture and doing square,are proposed to eliminate the code division interference,of which,the former one obtains Doppler frequency at the same time of PN code capture,while the later one can eliminate the bad effect of CDMA effectively and acquire Doppler frequency precisely,which is simple and practical.The experimental results show that the two algorithms for eliminating code division interference have their own advantages,and they can be selected and used as needed in practical engineering applications.关键词
码分干扰/载波捕获/码分多址/FFT/双向捕获/增加平方算法Key words
code division interference/carrier frequency acquisition/CDMA/FFT/bidirectional searching capture/doing square algorithm分类
电子信息工程
