BANDWIDTH AND SPECTRA OF PHASE- AND FREQUENCYMODULATED WAVES,
Abstract
The spectrum of a cosine angle-modulated by a Gaussian random process (GRP) of (almost) arbitrary spectrum is investigated. Such a GRP provides a convenient model for voice signals, TV signals, and other types of complex communication signals. A simple closed form expression for the bandwidth of the modulated signal in terms of the bandwidth of the modulating signal is found. A general expansion for the shape of the spectrum of the modulated cosine is derived.. In addition to reducing, in certain limiting situations, to known results, this expansion provides a practical means of obtaining the spectrum in intermediate cases. Examples are presented showing the spectrum of a cosine modulated by (1) a lowpass GRP with rectangular spectrum, and (2) a bandpass GRP of Gaussian spectrum. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1962
- Accession Number
- AD0441214
Entities
People
- Norman Abramson
Organizations
- Stanford University