Compact Antenna Test Range EVM Measurements of a Millimeter-Wave Phased Array using a VNA

Compact antenna test ranges (CATR) are favorable for over-the-air (OTA) measurements of millimeter-wave phased arrays because they use a feed and parabolic reflector to emulate the plane wave condition of far field ranges within a significantly-reduced volume, which reduces OTA path loss and compensates for the limited dynamic range of test instruments such as vector network analyzers (VNA). Error vector magnitude (EVM) is a measure of digitally-modulated signal quality that is increasingly used to benchmark the beamforming performance of millimeter-wave phased arrays, since it includes the effects of each element's radiated power and RF integrated circuit (RFIC) linearity across the signal bandwidth. This paper highlights EVM measurements of independent phased array elements in a CATR using spectrum analysis on a VNA receiver, performed at Keysight in Santa Rosa, CA, USA.