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 a 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.