A Multi-band Frequency Synthesizer for GSM/DCS/WIMAX/WLAN Applications with Ripple-free Circuit

Abstract

This paper presents a fully integrated multi- band frequency synthesizer implemented in CMOS 0.18 mu m process with ripple-free circuit in a single loop. The synthesizer is designed for GSM/ DCS/WIMAX/WLAN (802.11a/b/g) systems applying to IQ phase based transceivers. The proposed synthesizer with ripple-free circuit can reduce the amplitude of control voltage ripple. The synthesizer performs the suppression of 31.4dB in the spectrum of reference-spur and the peak-to-peak jitter with 74% improvement compared to the conventional single loop synthesizer design.