A low-power CMOS Bluetooth RF transceiver with a digital offset canceling DLL-based GFSK demodulator

Abstract

This paper presents a fully integrated 0.18-m CMOS Bluetooth transceiver. The chip consumes 33 mA in receive mode and 25 mA in transmit mode from a 3-V system supply. The receiver uses a low-IF (3-MHz) architecture, and the transmitter uses a direct modulation with ROM-based Gaussian low-pass filter and direct digital frequency synthesizer for high level of integration and low power consumption. A new frequency shift keying demodulator based on a delay-locked loop with a digital frequency offset canceller is proposed. The demodulator operates without harmonic distortion, handles up to 160-kHz frequency offset, and consumes only 2 mA from a 1.8-V supply. The receiver dynamic range is from 78 dBm to 16 dBm at 0.1% bit-error rate, and the transmitter delivers a maximum of 0 dBm with 20-dB digital power control capability.Index Terms-Bluetooth, CMOS integrated circuits, radio transceivers, Gaussian frequency shift keying (GFSK) demodulator.