正交通道中码分干扰对载波捕获的影响分析及研究OACSTPCD

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.