Table of Contents
International Journal of Microwave Science and Technology
Volume 2009 (2009), Article ID 715641, 7 pages
http://dx.doi.org/10.1155/2009/715641
Research Article

Low Phase Noise and High Conversion Gain Oscillator Mixer Constructed with a 0.18-m CMOS Technology

Institute of Electronic Engineering, Chang Gung University, no. 259 Wen-Hwa 1st Road, Kwei-Shan Tao-Yuan, Taiwan

Received 25 August 2009; Revised 24 September 2009; Accepted 13 November 2009

Academic Editor: Liang-Hung Lu

Copyright © 2009 Chin-Lung Yang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This paper presents a compact down-conversion oscillator mixer fabricated with a 0.18-m CMOS technology. The oscillator mixer consists of a conventional nMOS differential coupled oscillator, a switch stage, and a pMOS cross-coupled pair which is used to release the design constraint between the conversion gain and the start-up condition. Since the switch stage and the pMOS cross-coupled pair are stacked on the nMOS differential oscillator, the bias currents of the switch stage and the pMOS cross-coupled pair can be entirely reused, so as to reduce the power dissipation. The experimental results show a conversion gain of 6.5 dB at 2.1 GHz associated with a single-sideband (SSB) noise figure of below 13 dB. The oscillator mixer also exhibits a tuning range of 184 MHz and a phase noise of 116 dBc/Hz at 1-MHz offset from the LO frequency of 6.8 GHz, and it consumes 11 mA from 1.8 V bias voltage.