Status of Six-Port Technology for Wireless Sensing Applications

The status of the six-port technology for wireless sensing applications in the microwave and millimeter-wave regimes is discussed. The six-port technique has been introduced in the 1960's for power measurement and vector network analysis. Thanks to reduced hardware resource in contrast with conventional and well-established down-mixing heterodyne technique, new opportunities can be foreseen to address future sensing applications in a broad range of topics.