An Improved Power Expectation Propagation Detector for Massive MIMO Systems.

Expectation propagation (EP) achieves promising performance under various antenna configurations and modulations in massive multiple-input multiple-output (MIMO) detection. Among existing EP variants, the improved EP (IEP) achieves the best bit-error-rate (BER) performance, but at the expense of slower convergence rate. In this correspondence, a novel power EP (PEP) detector is proposed to further enhance the efficiency of EP by balancing the convergence rate and BER performance with two variance-control factors derived from minimizing the $\alpha$ -divergence in the moment matching. Numerical simulation results are illustrated to show that the proposed PEP can outperform state-of-the-art EP-based detectors in various MIMO scenarios.