Multiuser detection with particle filtering

In this paper, we apply particle filtering to multiuser detection (MUD) in synchronous CDMA systems with perfect channel state information (CSI). To apply particle filtering to MUD, first we find a factored representation of the posterior distribution. We show that the whitened matched filter (WMF) output allows such representation. No system approximations are made and the method is "soft" in nature. As a result, a near optimum performance is observed in simulations both in the equal power case and the near-far case. Since the computational complexity of the method is not exponential with the number of users, the method may have potential for industrial application.