Analysis and Design of Quadrature Oscillators

by Luis B. Oliveira; Jorge R. Fernandes; Igor M. Filanovsky; Chris J. M. Verhoeven; Manuel M. Silva

• ISBN13: 9781402085161
• ISBN10: 1402085168
• Format: Nonspecific Binding
• Copyright: 2008-07-08
• Publisher: Springer Nature

Summary

Nowadays, the demand for mobile and portable equipment has led to a large increase in wireless communication applications. Modern transceiver architectures, to achieve full integration and low cost, require quadrature oscillators with very accurate quadrature relationship, since quadrature errors affect strongly the overall performance of the RF (Radio Frequency) front-end. In this thesis we study and compare three types of quadrature oscillators, which are suitable for modern transceiver architectures: cross-coupled relaxation and LC oscillators, and two-integrator oscillators. The first two oscillators with single output are well known, and have been extensively studied. In this work we consider how to obtain quadrature outputs and investigate the performance of the quadrature oscillators. In this thesis we show that the mixing function can be incorporated in the quadrature oscillators by injecting a modulating signal in the feedback loop of the oscillators. The oscillator quadrature relationship is preserved, and this approach has the advantage of reducing area and power consumption in a transceiver. This oscillator-mixer concept was confirmed by measurements on a 5 GHz quadrature relaxation oscillator-mixer prototype.