Novel wideband six-port receiver structure

Typical Six-Port Direct Receiver (SPDR) comprise a six-port junction, made of power dividers and hybrids, and four matched power detectors. This kind of circuit is difficult to implement in MMIC (Monolithic Microwave Integrated Circuit) technology, due to its sensitivity to fabrication tolerances. Some simple six-port structures have been recently proposed which are more suitable for integration. However, these structures exhibit a direct path between LO and RF ports, which is undesirable for homodyne receiver operation. This work presents a novel and simple wideband SPDR with high isolation between LO and RF ports. Owing to its ease of implementation and high performance, it is a good candidate to be used in low-cost mass-market radio receivers.