Accession Number:

AD0275761

Title:

SPECTRAL CHARACTERISTICS OF RANDOM MODULATED WAVES

Descriptive Note:

Corporate Author:

JOHNS HOPKINS UNIV BALTIMORE MD CARLYLE BARTON LAB

Personal Author(s):

• LAUDERDALE, L. K.

Report Date:

1962-05-01

Pagination or Media Count:

88.0

Abstract:

The spectral characteristics of random modulated waves are investigated with particular emphasis on the determination of power density spectra of sinusoids that are frequency modulated by bandpass Gaussian noise. Pertinent parts of the theory of random processes necessary for spectral analysis are reviewed, and a general formulation of the problem of determining spectral characteristics of random modulated waves is given. Limiting cases of large and small modulation indices are discussed, and a technique is developed for obtaining useful approximations of FM by band-pass noise spectra. These results are verified by digital computations and experimental measurements. Finally, spectra resulting from FM by the combination of band-pass noise and a sinusoid, and simultaneous AM by low-pass noise and FM by band-pass noise are investigated.

Descriptors:

• *FREQUENCY MODULATION
• *RADIO WAVES
• *NOISE(RADIO)
• TIME
• STATISTICAL DISTRIBUTIONS
• OSCILLOGRAPHS
• STATISTICAL PROCESSES
• BANDPASS FILTERS
• FUNCTIONS(MATHEMATICS)
• FOURIER ANALYSIS
• PROBABILITY
• TAYLORS SERIES
• DENSITY
• INFORMATION THEORY

Subject Categories:

• Radiofrequency Wave Propagation
• Radio Communications

Distribution Statement:

APPROVED FOR PUBLIC RELEASE