基于邻近频点插值混合扩频信号多普勒频偏估计算法

Aiming at the problem of reducing Doppler frequency estimation error in the case of limited computation resources, when using the acquisition algorithm of direct sequence/frequency hopped (DS/FH) hybrid spread spectrum signals, a frequency estimation algorithm based on interpolation prediction was adopted. Correlation values at different frequency points were used to estimate Doppler frequency offset to reduce the Doppler frequency error, at the expense of relatively lower computation amount. Under different signal-to-noise ratio (SNR) environments and different Doppler frequencies of received signal, Doppler frequency detection accuracy was simulated. The tests show that when the SNR is no less than -23 dB, the average Doppler frequency estimation error for DS/FH hybrid spread spectrum system is less than 20 Hz and has more stable root-mean-square errors. Doppler frequency estimation accuracy can be improved by post-computation, with no need of considerable hardware alteration.