Channel Estimation in MIMO–OFDM Systems Based on a New Adaptive Greedy Algorithm

Channel estimation methods based on compressed sensing can be used to effectively obtain channel state information of MIMO-OFDM systems. This letter proposes a new adaptive matching pursuit (NAMP) algorithm and the evaluation prototype based on the LTE-Advanced wireless channel model. First, NAMP does not need the priori-knowledge of the sparsity level. Second, the fixed step size is determined in order to improve the efficiency of signal reconstruction. Third, a singular entropy order determination mechanism is employed to prevent the less relevant atoms from being introduced. Finally, simulation results are discussed in detail, which demonstrate that the proposed method results in lower computational complexity, and especially achieves more stable performance.