文档介绍：This chapter appears in the book "Analog Circuit Design-RF Analog-to-
Digital Con-verters; Sensor and Actuator Interfaces; Low-Noise Oscillators,
PLLs and Synthesizers", published by Kluwer Academic Publishers, Boston,
November 1997, 428 pp. Hard-bound, ISBN 0-7923-9968-4
frequency (IF), then the phase noise around fLO will
How Phase Noise Appears in Oscillators downconvert nearby channels on to the same IF. As will
shortly emerge, fundamental reasons dictate that the phase
noise spectral density is always highest at f and falls off at
Asad A. Abidi LO
Integrated Circuits & Systems Laboratory frequencies away from it. Thus the largest expected strengths
Electrical Engineering Department of the immediately adjacent channels set a limit on the
University of California, Los Angeles tolerable phase noise close-in to the receiver LO frequency. In
******@ modern munication systems with power control
such as GSM and DECT, the allowed strength of nearby
ABSTRACT channels must conform to a template roughly inverse to the
Wireless transceivers closely specify the phase noise oscillator phase noise specification.
in the local oscillator. Yet it is not very well Phase noise in the transmitter LO — very often this is the
understood how phase noise is predicted, especially same oscillator as is used in the
in oscillators which do no