Joint Symbol Detection and Multi-Channel Acquisition in Fast-Fading Narrowband Wireless Environments

"We address the problem of joint source symbol detection and multi-channel estimation in time-selective digital communication scenarios. Our approach is based on a statistical model which decouples the time dynamics of the multi-channel vector in amplitude and direction. We compute the most probable emitted symbol sequence and channel realization for this statistical model, given the set of array observations. Our maximum a posterior (MAP) receiver consists of a bank of parallel processors. Each processor finds the most probable channel realization for a given symbol sequence via a relaxed semidefinite programming (SDP) reformulation of the original estimation problem. Computer simulations are included to assess the capability of our technique in acquiring fast-changing flat-fading channels."