Accession Number : ADA300070

Title :   Physically Adaptive Antennas.

Descriptive Note : Final rept. Jun-Oct 93,

Corporate Author : MARYLAND UNIV COLLEGE PARK DEPT OF ELECTRICAL ENGINEERING

Personal Author(s) : Ho, Ping-Tong

PDF Url : ADA300070

Report Date : AUG 1995

Pagination or Media Count : 52

Abstract : A reconfigurable antenna concept, consisting of a semiconductor illuminated by an optical or electron source, was studied. With appropriate-illumination, mobile charge carriers excited from the valence band to the conduction band can form a conducting antenna pattern in the semiconductor material. Calculations of gain and radiation resistance for linear dipole and "bow-tie" layouts were completed to estimate source power requirements and practical wavelength limits for such an antenna. Significant findings were that source power for writing a reconfigurable antenna increases as the square of the radiation wavelength; and that semiconductor material permittivity limits antenna efficiency to about one-tenth that of a comparable free-standing antenna. Frequency agility in the antenna may be possible using an electronically controllable liquid crystal display, semiconductor laser array, or electron emitter tips.

Descriptors :   *COMPUTATIONS, *DIPOLE ANTENNAS, FREQUENCY, REQUIREMENTS, SOURCES, RADIATION, MATERIALS, ARRAYS, SEMICONDUCTOR LASERS, SEMICONDUCTORS, ELECTRONS, VALENCE BANDS, LIMITATIONS, SILICON, GAIN, POWER SUPPLIES, CONDUCTION BANDS, ANTENNA RADIATION PATTERNS, FREQUENCY AGILITY, RADIATION RESISTANCE.

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE