Six-port receiver in millimeter-wave systems

A six-port V-band heterodyne receiver architecture is proposed in this paper. The millimeter-wave frequency conversion is performed using a passive circuit module, the six-port, avoiding the conventional millimeter-wave active costly mixers. Basically, the six-port circuit is an additive mixer in which the resulting sum of millimeter-wave signals is nonlinearly processed using millimeter-wave detectors. This proposed module, constructed using 4 rat-race couplers (180´) will be used in millimeter wave receiver system. This paper shows how this new module together with related power RF detectors is performing the first frequency conversion, avoiding the conventional millimeter-wave active costly mixers. The second frequency conversion uses conventional means due to the low IF value. This frequency conversion is demonstrated by showing the demodulation results (MPSK/QAM) of our receiver system using this new six-port and RF detectors.