Pilot allocation approaches for channel estimation in MIMO relay networks
Abbas Akbarpour‐Kasgari, Mehrdad Ardebilipour · IET Communications · 2018
Distributed‐compressed sensing (DCS)‐based channel estimation of multiple‐input multiple‐output (MIMO) orthogonal frequency division multiplexing for relay communication is considered in this study. Specifically, the pilot allocation is addressed to optimise the channel estimation performance. All the existing works on DCS‐based channel estimation pilot placement discussed on the mean square error (MSE) of the estimation probabilistically based on the mutual coherence. On the contrary, the authors try to address the MSE of the estimation directly and optimise the MSE directly and design a pilot pattern to optimise the performance of the estimation. By taking into account the optimisation approach, two combinatorial stochastic algorithms have been presented. These two algorithms utilise cross entropy approach in sequential and parallel form. Simulation results represent that the DCS‐based MIMO relay channel estimation using optimised pilot placements will increase the performance from 3 to 12 dB as compared with the conventional least squares (LS) method. Furthermore, parallelism has demonstrated the performance gain. Moreover, the DCS‐based MIMO relay channel estimation shows improvement in spectrum efficiency under the same bit error rate performance over the traditional LS‐based channel estimation approach, respectively.