OPTIMUM DEMODULATION OF PM AND FM SIGNALS
Abstract
This report presents results of investigating the limiting performance attainable with angle modulation (PM and FM) receivers. Statistical estimators which implement the criteria of minimum mean-square-error (MMSE) and maximum a posteriori probability (MAP) are compared with phase-locked loops. Mathematical investigations were carried out for the threshold region. Asymptotic formulae were developed where applicable; the region which could not be effectively treated analytically was analyzed by using a digital computer. The threshold phenomenon of phase-locked loops was investigated by means of a hybrid computer simulation. The results indicate that all properly designed demodulators for angle-modulation signals attain the same improvement above threshold, and that the major difference in demodulation techniques lies in the location of the threshold. The limitations of the FM threshold are explicitly brought out, and the factors which limit the extension of present-day threshold are pointed out. The maximum amount of threshold extension which it is theoretically possible to attain is determined.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1967
- Accession Number
- AD0820392
Entities
People
- Harold D. Becker
- John G. Lawton
- John T. Vleck
- Sol Kaufman
Organizations
- Calspan