MCMC Based Bit-wise Detection for OTFS Modulation with Complexity Reduction

The orthogonal time frequency space (OTFS) modulation as a promising signal representation attracts growing attention for integrated sensing and communication. This paper devotes to signal detection for OTFS system. Notice the characteristics of high dimension and sparsity of OTFS channel, we propose a bit-wise detector based on Markov Chain Monte Carlo (MCMC) method with reduced complexity. We simplify the Gibbs iteration process since the channel sparsity indicates that for a given transmitted symbol, only limited received symbols are associated with it, and vice versa. Simulations in various cases demonstrate the feasibility of the proposed algorithm.