Accession Number : AD0482536

Title :   MODULATION PHENOMENA IN A TIME-VARYING TRANSMISSION SYSTEM.

Descriptive Note : Interim task rept. no. 15,

Corporate Author : SYRACUSE UNIV NY DEPT OF ELECTRICAL ENGINEERING

Personal Author(s) : Sherman, Martin ; Perini, Jose

Report Date : APR 1966

Pagination or Media Count : 35

Abstract : Sidebands have been observed in the transmission of monochromatic radiation from systems composed of long wire antennas fed by parallel-wire transmission lines. As the wires composing such systems are very long and are supported at relatively few points, it has been suggested that the modulation is introduced by the vibration of these wires in the wind. In this report this possibility is investigated for two specific cases: (a) harmonic change in the characteristic impedance of the transmission line, which leads to amplitude modulation; and (b) harmonic change in the phase velocity along the transmission lines, which leads to frequency or phase modulation. Some numerical examples are given which tend to show that only extreme variations of the (a) or (b) types can cause the sidebands to be of the order 40db below the carrier level. (Author)

Descriptors :   *MODULATION), (*WAVE PROPAGATION, ANTENNA RADIATION PATTERNS, WIRE, TRANSMISSION LINES, ELECTRICAL IMPEDANCE, AMPLITUDE MODULATION, PHASE MODULATION, FREQUENCY MODULATION, SIDEBANDS.

Subject Categories : Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE