Accession Number : AD0710832

Title :   SERRASOID GENERATION FOR EXTENDED-RANGE FREQUENCY MODULATION,

Corporate Author : ILLINOIS UNIV URBANA COORDINATED SCIENCE LAB

Personal Author(s) : Kubala,Robert John

Report Date : AUG 1970

Pagination or Media Count : 53

Abstract : Wideband frequency-modulated signals may be produced by an extension of the Armstrong method if suitable cosine phi and sine phi waveforms are generated, where phi is the phase of the modulated signal. The generation of these involves complex and expensive circuitry in which parameters must be continuously and accurately varied. It is possible to first generate serrasoidal waveforms analogous to cosine phi and sine phi which can be converted to the latter. Such serrasoidal signals could conceivably be simple to generate, since corresponding circuitry involves only integrators, threshold detectors, and polarity-switching gates; circuits which are linear except during brief switching periods. Two esperimental serrasoid generators were constructed whose designs are described. Adverse response to small input signals occurred, and appear inherent to the technique. This response, and the relative complexity of suitable polarity-switching gates indicate that the described approach cannot favorably compare with more conventional frequency-modulation schemes.

Descriptors :   (*WAVEFORM GENERATORS, DESIGN), FREQUENCY MODULATION, BROADBAND, INTEGRATED CIRCUITS, INTEGRATORS, THESES

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE