Hybrid-Based Propagation Parameter Estimation Method Using EM/SAGE and Extended MODE Algorithm

MIMO transmission technologies have been investigated and are expected to realize the wide-band and high-speed radio communication in LTE and IMT-A systems. To put those technologies into practical use, the accurate MIMO channel is required. To estimate the propagation parameters of rays from the channel data measured by the channel sounder, the SAGE based estimation algorithms have been used. SAGE algorithm is able to be applied to any patterns of antenna arrays, and can estimate the several propagation parameters such as AoA, AoD, delay and amplitude in parallel. However it has the resolution degrading problem in the case that there are close rays that have the close propagation parameters. In the paper, we propose the novel channel estimation methods. In our proposal, after the global parameter estimation using SAGE algorithm, we extract the signal component of the close rays from the measured data. Then we execute detailed parameter estimation for those rays using MODE based algorithm with the array interpolation. We show the effectiveness of our proposal through the computer simulation.