Block Detection of Multiple Symbol DPSK in a Statistically Unknown Time-Varying Channel

We present a detection scheme for multiple-symbol DPSK for use in a statistically unknown time-varying channel. The scheme relies on a parametric representation of the time- varying channel, resulting in a reduction in the number of parameters required to be determined by optimizing a maximum likelihood sequence estimation (MLSE) type cost function. We also present a reduced-complexity version of the detection scheme based on sphere decoding. Analysis and simulations show good performance in Rayleigh fading over varying degrees of channel time-variation for an appropriately selected channel parameterization.