A New Dual Loop Frequency Synthesizer for the Wireless Standard 802.11g

Abstract

A new type of frequency synthesizer is proposed in this paper. It employs a variable frequency reference, a digital phase lock loop (PLL) including a dead zone circuit for the coarse frequency control, and an analog PLL for the fine frequency control. This structure allows the replacement of the classical variable ratio fractional frequency divider by a constant integer ratio one, that allows a significant reduction of the phase noise.