Low Power FSK Receiver Using an Oscillator-Based Injection-Locked Frequency Divider

Abstract—This letter presents a novel frequency-shift keying (FSK) receiver using an oscillator-based injection-locked fre-quency divider (ILFD), thereby achieving high sensitivity, low dc-offset, and low power consumption. The proposed receiver com-prises a low-noise amplifier, a divide-by-2 ring-oscillator-based ILFD, and a subharmonic mixer. Moreover, the proposed receiver is fabricated using 0.18 CMOS process and consumes 1.1 mW. Measurement results demonstrate that the proposed receiver has a sensitivity of 83 dBm at bit error rate with 1 Mb/s data rate in receiving a 2.4 GHz Gaussian FSK signal. Index Terms—CMOS FSK receiver, injection-locked frequency divider (ILFD), ring oscillator, subharmonic mixer. I