Experimental Verification of a Plane-Wave Field Synthesis Technique for MIMO OTA Antenna Testing

Abstract

This paper evaluates the feasibility of a plane-wave field synthesis (PWS) technique for multiple-input multiple-output (MIMO) over-the-air (OTA) test facility, where a reference channel model is implemented. The test facility is based on a fading emulator and an anechoic chamber, equipped with multiple field emulating probes. The test facility emulates a radio channel condition using the PWS technique, based on the spherical wave theory. A simulation tool implementing the MIMO OTA field synthesis based on the PWS technique, named WIN-OTA, is established, where the WINNER II is chosen as the reference channel model. The simulation results show that the PWS technique reproduces the reference channels accurately in terms of envelope distribution, spatial and temporal correlation, and channel capacity. The WIN-OTA implementation was verified by comparing the emulated fields and the throughput from the simulations with the measurements for a practical MIMO OTA test facility. The results support the feasibility and accuracy of the field synthesis technique and the WIN-OTA implementation in MIMO OTA antenna testing.