An Enhanced EM/SAGE-based H-infinity Channel Estimator for MIMO-OFDM Systems

作者：Xu Peng^*; Wang Jinkuan; Qi Feng; Song Xin

来源：Chinese Journal of Electronics, 2011, 20(4): 708-712.

• Orthogonal frequency division multiplexing (OFDM)
• Multiple-input multiple-output (MIMO)
• Channel estimation
• H-infinity
• Expectation maximum (EM)
• Space-alternating generalized EM (SAGE)
• Phase shifted orthogonal (PSO)

This paper proposes a low-complexity and robust H-infinity channel estimator for Multiple-input multiple-output (MIMO) Orthogonal frequency division multiplexing (OFDM) systems. To lessen the complexity, the Expectation maximization (EM) and Space-alternating generalized EM (SAGE) algorithms are adopted respectively. To treat with the effect of Non-Gaussian noise (NGN) channels, an Equivalent signal model (ESM) is used to enhance the robust of the EM-type H-infinity estimator. Furthermore, joint estimation using Phase shifted orthogonal (PSO) pilot sequences is applied for improving the estimation and the requirement for pilot. Simulation results show that the H-infinity estimator has almost the same Mean square error (MSE) as Maximum a posteriori (MAP) estimator. By using the ESM, the robustness of EM-type based H-infinity estimator is enhanced against NGN channels. In addition, the MSE and pilot overhead are reduced by applying the joint estimation with PSO.

• 出版日期2011-10
• 单位东北大学