Probe Selection Method based on Switch Matrix for 5G Massive MIMO Base Station OTA Testing

The sectored multi-probe anechoic chamber method (MPAC) is considered to be the most promising method for 5G massive multiple-input multiple-output (MIMO) base station (BS) over-the-air (OTA) testing. In this case, the number of channel simulators and probes used in the testing system is increasing to reproduce the wireless propagation channel in a laboratory environment, which leads to a significant increase in the cost of the testing system and the complexity of probe selection. In this paper, a group-based switch matrix and corresponding probe selection algorithm are proposed. The simulation results indicate that the proposed method can accurately reconstruct the channel environment around the device-under-test (DUT) with fewer probes and lower computational complexity. Additionally, the impact of different probe configurations on the accuracy of channel emulation is also discussed.