A transmission direction adaptive RF power supply system for wireless sensor nodes

RF-powered Wireless Sensor Networks frequently experience severe energy constraints in dynamic environments, primarily due to the pronounced efficiency loss of RF energy transmission over distance. This paper proposes a transmission direction adaptive RF power supply system for wireless sensor networks, implemented via a dynamic energy transmission model and directional control algorithm to achieve real-time adjustment of transmitter gain direction during movement. The proposed system consists of three main layers: the motion layer for mobility, the core layer for power and control, and the transmission layer for energy delivery. It has dimensions of 19 cm × 8 cm × 23 cm and a power consumption of 5.62 W, featuring low energy and high integration. Experimental results demonstrate a 30 % voltage increase and 70 % harvested energy enhancement for a 220 mF capacitor, validating significant efficiency gains in dynamic environments. By maintaining optimal alignment between mobile RF sources and receivers, the system compensates for efficiency decrease caused by distance, overcoming limitations of static transmitters.