Analysis of receiver space diversity gain for millimeter-wave self-heterodyne transmission techniques under two-path channel environments

Receiver space diversity based on millimeter-wave self-heterodyne transmission technique is demonstrated and its effective gain in two-path channel environments is theoretically and experimentally characterized. Under two-path channel environments, it is shown that the outputs of two receiver diversity modules have different amplitude but almost same phases without employing any millimeter-wave band phase-shifter. With this in-phase combining, signal-to-noise ratio (SNR) performance is improved without suffering from multi-path signal fading phenomena