本程序是基于ofdm调制方式的多普勒频移的产生和估计，因为OFDM中也会产生频移从而影响它的各个符号的正交性！-estimation of doppler shift based on OFDM

Application of spread spectrum for satellite land mobile systems is difficult in satellite link because of synchronization and providing code or considerable Doppler shift. This is particularly high for LEO satellites. So that, a Doppler shift carr