低轨移动卫星异步多用户检测算法

Asynchronous Multiuser Detection Algorithm for LEO Mobile Satellite Receiver

介绍了一种适合在低轨(LEO)星载接收机上运行、低复杂度的异步CDMA多用户检测算法,能够有效对抗强多用户干扰和大多普勒频移。基带信号通过码片滤波后以码速率采样信号作为观测信号,然后利用Kalman滤波算法对各个用户信号进行分离。状态方程综合考虑了多普勒频移、定时误差。该算法能够抵抗高达35dB的远近效应,并且对频率和定时误差不敏感。

A low complexity asynchronous multiuser detection algorithm for on board LEO satellite receiver, which can resist strong multiuser interference and large doppler frequency drift is introduced. After chip match filter, base band signal was sampled at chip rate and used as observe signal. Then Kalman filter was used to separate multi-user signal. Doppler frequency drift and timing error were considered in state transform equations. The proposed algorithin can resist as high as 35dB near-far effect, and are senseless to frequency and timing error.