Direct conversion receivers using multiport structures for software-defined radio systems

An analytical assessment for multiport structures as direct conversion receivers is presented. A new direct-conversion receiver based on a novel five-port structure suitable for software-defined radio applications is proposed. The five-port architecture provides some advantages compared with previous architectures. Numerical and microwave simulations have been conducted to show its capabilities as a direct demodulator. The proposed five-port has been constructed and the measured results indicate that the five-port receiver introduced can be used effectively as a software-defined radio receiver