Gaussian frequency shift keying (GFSK) modulation is widely used in low data-rate personal communication standards like Bluetooth. For the purpose of low power and low cost, GFSK transceivers are usually designed in the analog domain. To improve bit error rate (BER) performance and the integration capability for diverse and complicated applications, the digital GFSK demodulation technology becomes attractive. A digital GFSK transceiver is studied in this paper where a new and simple carrier synchronizer is proposed. The new carrier synchronizer uses a decision-aided data cancellation algorithm to estimate carrier frequency offset. The complete GFSK transmission simulation is performed and almost ideal BER performance is achieved in the additive white Gaussian noise environment.