A 5.2 GHz BFSK receiver with on-chip antenna for self-powered RFID tags and medical sensors

A completely integrated receiver design suitable for short range wireless applications is presented. The circuit represents one half of an SoC solution that makes use of an on-chip antenna, and consumes 5.5 mW while receiving. A thin film ultracapacitor and a solar cell can be stacked on top of the chip to supply power to the radio; yielding a completely integrated solution. The receiver makes use of a PLL to initially lock an RF VCO which is then allowed to be injectionlocked to an incoming FM signal. An integrated antenna provides adequate gain given the short range radio's intended applications. The solution has a communication range of 1.75 m which can be increased at the expense of the bit-rate, increased power consumption in the receiver, or by using off-chip antennas.