Sparse channel estimation algorithms for OTFS system

Orthogonal time-frequency space (OTFS) modulation, which has recently been proposed in the literature, is one of promising techniques designed 2D Delay-Doppler domain adapted to combat high Doppler fading channels. However, channel estimation scenarios advanced mobile-communication systems still a challenging task. In this paper, problem OTFS focused on. First, simple adaptation generalized orthogonal matching pursuit procedure, will serve as baseline method work, proposed. Then, iterative algorithms are derived beneficiating from sparsity channel. The unknown vector separated into an sparse support corresponding delay and taps, gains. These involve ℓ1-norm minimization two-stage procedure recover alternatively its coefficients. also addressed Bayesian point view. representation reformulated specific marginalization maximum posteriori on To deal with intractability problem, two existing context, namely: Monte Carlo Markov chain Gibbs sampler variational mean-field approximation expectation-maximization procedure. Finally, assess performance algorithms, their complexity compared against methods. Experimental tests, conducted high-mobility low-latency applications, show that schemes slightly more expensive terms load but perform significantly better normalized mean square error bit rate.