A Probabilistic Approach of Joint Channel Estimation and Symbol Detection for OSTBC

In this paper, we propose a probabilistic technique to achieve joint channel estimation and symbol detection for orthogonal space time block coding (OSTBC) systems. The key result is that a multiple-input single-output system using OSTBC can be translated to an equivalent single-input multiple-output system using the implicit redundancy in OSTBC. This allows some probabilistic methods to be applicable at each output branch. Since each output branch is excited by the same input, redundant information can be exchanged between the multiple branches to improve the detection performance at individual branches. The proposed technique has the potential to be concatenated with a channel decoder and form a turbo receiver. The performance of the proposed algorithm is demonstrated through simulation results and compared with an existing scheme.