Study on quasi-millimeter-wave WiCoPT system and development of circuits for the system

Recently, Wireless Communication and Power Transmission (WiCoPT) system, which transmit electric power and information simultaneously using radio wave, is studied in many research organizations. To transmit electromagnetic power efficiently, an active integrated antenna (AIA) is usually used. This is the same technology with Massive MIMO for 5th generation mobile communication system (5G). Information signal is up-converted to transmitting signal of quasi-millimeter-wave. In this paper, link budget for a battery-less sensor network is studied and performances of developed circuits for the system are reported. First, amplifier using discrete FET with plastic package is developed. In order to design circuit accurately, effects of parasitic components are studied. For up-converter, Single Ended Mixer (SEM) is adopted and BPFs are placed at input and output of SEM to remove image signal and local leakage. To reduce conversion loss, unique BPF is developed and length of connecting lines between SEM and BPF is optimized. For duplexing, SPDT switch using FET is also developed. The performances of these devices are confirmed by experiments.