A 580- $\mu$ W 2.4-GHz ZigBee Receiver Front End With Transformer Coupling Technique

This letter presents a 2.4-GHz sliding-IF ZigBee receiver front end for wireless sensor networks. The receiver targets extreme high energy efficiency by sharing its power between all RF blocks. It employs a 0-V supply passive gain booster and mixers combo with its power coupled from the voltage-controlled oscillator (VCO) by using the transformer coupling technique. The quasi-passive mixer and quadrature passive mixer down converts the RF signal to the baseband without need of the dc supply voltage. The VCO achieves a phase noise of -110 dBc/Hz at 1 MHz while dissipating 580 μW. The RF front end demonstrates the conversion gain of 13.5 dB, noise figure of 6.1 dB, and IIP3 of -9.4 dBm at the frequency band of 2.41-2.53 GHz.