On Symbol-Wise Variational Bayesian CSI Estimation and Detection for Distributed Antenna Systems Subjected to Multiple Unknown Jammers

This letter develops a novel iterative joint channel state information estimation (CSIE), jammer estimation (JE) and data detection (DD) algorithm for orthogonal frequency division multiplexing (OFDM)-based distributed antenna systems in the presence of multiple unknown jammers. In contrast to existing methods that only heuristically combine CSIE, JE and DD, the proposed algorithm rigorously casts the three problems under a unified variational Bayesian inference framework. Simulation results demonstrate that the proposed algorithm converges rapidly, and after convergence, the bit-error-rate performance of the proposed algorithm is very close to that of the ideal case which supposes perfect knowledge of CSI and jammer. In addition, it is shown that the proposed algorithm significantly outperforms other state-of-the-art methods.