Single-stage RF quadrature front-end receivers for ultra low power applications

A very compact and flexible single stage RF front-end for low power receiver is presented. The key feature of the circuit proposed is the large separation of the different functions implemented (RF amplification, mixing, LO and quadrature generation) even while sharing the same bias current and the same devices. Two different prototypes are reported. The first one is a RF front-end for GPS applications with a noise figure of 4.8 dB, a gain of 36 dB, an IIP3 of -19 dBm and a power consumption of only 5.4 mW. The second design is a ZigBee receiver with a noise figure around 9 dB, an IIP3 of -12.5 dBm and a power dissipation of 3.6 mW (including baseband filter).