Nonlinear Distortion Investigation Using mm-Wave Over-the-Air SISO and MISO Measurements

This paper demonstrates different use cases in Over-the-Air (OTA) measurements to differentiate between different sources of distortion, for the purpose of receiver characterization. We propose to use both single-input single-output (SISO), as well as multiple-input single-output (MISO) test cases. To demonstrate the method, we operated the Chalmers mm-wave MIMO testbed, MATE, at 29.4 GHz in a line of sight test configuration. For the MISO case, a beamforming algorithm is used to steer the beams at one RX. The algorithm exhibits measurement results that agree well with theoretical analysis and are sufficiently stable over time. By sweeping the transmit power, in the SISO and MISO cases, the sources of distortion can be clearly differentiated.