In this work, a wireless sensor node technology is developed in which the sensor nodes are powered wirelessly to ensure battery-less operation. A planar inverted-F antenna is designed at 860 MHz for rectenna implementation that is capable of harvesting $48\ \mu \mathrm{W}$ power at 4 m transmission distance. Low power BLE transceiver is used to data communication between the sensor node and the base station. All functional blocks including the antenna are implemented in a limited board area of $6\times 4\ \mathrm{cm}^{2}$ . The BLE data protocol is optimized to ensure energy efficient operation, and it helped to achieve continuous and self-sustain operation of the sensor node.
