Co-channel operation of microwave power and IEEE 802.11-based data transmissions: A feasibility study

This paper reports a feasibility study including experimental implementation of a battery-less wireless sensor whose power is supplied by a microwave power transmitter. In particular, both microwave power transmissions (MPTs) and wireless communications using wireless local area networks (WLANs) are performed on the same frequency band, 2.4 GHz, to achieve high spectral efficiency. In this case, time scheduling of MPT and wireless communication is necessary to avoid interference. In addition, for stable operation, the duty ratio, which is defined as the ratio of the active duration to the whole period, is set depending on the charge remaining in the capacitor of the sensor. In the initial experimental setup, a single battery-less wireless sensor is successfully operated, and then the feasible transmission range of the designed time scheduling system is discussed.