Efficient Ray Tracing Simulation Framework for Massive MIMO Channels

This paper introduces an efficient ray tracing (RT) simulation framework for massive MIMO channels using the coarse-refinement scheme. Compared to the brute-force method, i.e., performing RT for each element pair in the massive MIMO array, the coarse-refinement method conducts RT only for sparsely located array elements, and then interpolates the RT results to remaining elements, hence significantly reducing the complexity compared with the brute-force method. The accuracy is guaranteed by capturing sphericaVastigmatic-wave propagation and the spatial non-stationarity (SnS) in the near-field (NF) region. A simulation in an indoor scenario demonstrates that the method can generate almost the same channel as the brute-force method, yet with significantly reduced simulation time.