Projeto e simulação de um oscilador controlado por tensão para aplicações envolvendo radares empregando compensação em temperatura

Abstract

Radar systems are capable of producing measurements with great accuracy. However, such capacity depends on the components used in the system and the way in which these components interact. The receptor-exciter (REX) is one of the most fundamental building blocks in high quality systems. The reference of a REX, and consequently of the system as a whole, is a stable local oscillator. This component can be produced through various technologies. Among them, LC oscillators built with integrated circuits technology have advantageous features such as low power consumption, short transient period and low phase noise. In this work the design of an LC oscillator developed using the TSMC 180 nm fabrication process devices is presented. Seeking to produce an oscillator suitable for radar systems, design techniques such as current reuse, Spontaneous Transconductance Match and constantbiased MOS capacitors are employed. Moreover, the temperature and quality factor variations influence over LC oscillators was verified. Simulations showed that the oscillator consumes about 7 mW, is able to generate sinusoidal signals between 8.331 GHz and 11.035 GHz, features superior frequency tuning range at 25 %, and produces phase noise below -110 dBc/Hz considering a 1 MHz offset from the component for all the evaluated conditions.