RF Circuits for 5G Applications

9RF Oscillators

Pramila Jakhar¹* and Amitesh Kumar^2†

¹Department of Electrical & Electronics Engineering, BITS Pilani K K Birla Goa Campus, Goa, India

²Department of Electrical Engineering, National Institute of Technology, Patna, India

Abstract

Oscillators are important circuits in Radio Frequency (RF) communication. The main building blocks of an oscillator are amplifier and a frequency-selective network in a positive-feedback. Significant requirement for oscillators used in RF applications should consist of proper amplitude controlled circuitry, low phase error and low power consumption. This chapter presents the important aspects for the design of RC and LC oscillator circuits.

Keywords: Phase noise to carrier ratio, RF oscillators, amplitude control, low power consumption, LC oscillators

9.1 Introduction

The oscillator is one of the important block in RF communication system at both transmission and receiver end. In a transmitter, it generates the signal. The local oscillator is used in conjunction with a mixer in a receiver to transform the received RF signal to an IF signal. A low-frequency analogue or digital signal can modulate the oscillator. The carrier in this example is the oscillator signal, and the information to be sent is the modulating low-frequency signal. High power output, high DC-to-RF efficiency, low noise, strong stability, good frequency tunability, and other characteristics of an oscillator would be desirable in the design of a system.

A wide number ...