Over-the-Air Measurement of Distortion Error-Vector-Magnitude in a Reverberation Chamber

This paper presents a novel measurement approach for characterizing the error vector magnitude (EVM) of a transmitter using a reverberation chamber (RC). The method is demonstrated by measuring a power amplifier (PA) connected to a passive antenna operating at 4.5 GHz. The EVM is estimated using commercial vector signal analysis (VSA) software. The approach discussed here does not require signal demodulation as is the case in conventional EVM computation, and therefore does not rely on a line-of-sight (LoS) connection. Preliminary results show agreement within 1% between conducted and over-the-air (OTA) measurements.