针对TDMA多时隙信号不连续,通信时隙外噪声以及其它用户信号影响时/频差参数估计的问题,首先证明了多时隙多普勒频差信号具有相参性,指出多时隙信号在相关处理中能量是可以积累的;在此基础上,根据通信时隙外噪声、其它用户信号与特定用户信号在时域上的可分离特性,提出基于解调分选的TDMA时/频差参数估计方法,并推导分析了该方法的处理性能。试验结果表明,提出的方法可以实现TDMA信号中多用户信号的时/频差参数联合估计,可以有效降低通信时隙外噪声与其它用户信号对参数估计精度的影响。
In joint estimation of DTO and DFO for TDMA signals,there are two problems.The first one is that signals of different timeslot are not continuous,and the other one is that the noise and signals out of timeslot have effect on the accuracy of parameter estimation.The coherence of signals with Doppler frequency offset in different timeslot is proved,and the conclusion is derived that signals of different timeslots can be used in the estimation of DTO and DFO.Then,according to the separation of signals of different users in time domain,the algorithm for joint estimation of DTO and DFO of TDMA signals based on signal demodulation and sorting is firstly proposed in domestic and abroad.Also,the performance of this method is derived and analyzed.The validity of proposed method is verified by computer simulation and experiments.