Nonlinearity analysis of power detectors in direct conversion receivers utilizing six-port technology

Within the six-port or five-port receiver, additive mixing followed by squaring of the respective signal is realized. For the squaring, power detectors are utilized. In this article, we investigate the influence of higher order nonlinearities of the power detectors. The focus is on the distortion of the baseband signal by nonlinear fractions which originate from the RF-signal. Among other things, it will be deviated that even the most simple power detector realizations can guarantee a sufficient transmission quality.