Probe Selection for 5G Massive MIMO Base Station Over-the-Air Testing

A sectored multiprobe anechoic chamber is seen as a promising method to carry out the radiated testing of massive multiple-input-multiple-output (MIMO) base station (BS), and realistic channel environment reconstruction is crucial for the performance assessment of wireless devices, especially for the testing of beamforming procedures, such as beam acquisition, tracking, and so on. This letter proposes a novel probe selection algorithm and corresponding device rotation scheme to enable more accurate channel emulation with specific probe antennas. On the other hand, within the acceptable threshold of error, the number of required probe antennas can be reduced, which will mitigate setup complexity and the number of hardware resources. In the simulation, to verify the robustness of the proposed probe configuration, several metrics are examined with different numbers of selected probes, in terms of spatial correlation and power angular spectrum emulation. The simulation results show that the proposed selection and rotation algorithms perform well in synthesizing the accurate target propagation environment on the BS side.