Accession Number : ADA304993
Title : Reconfigurable Antennas.
Descriptive Note : Final technical rept. Sep 94-Mar 95,
Corporate Author : MARYLAND UNIV COLLEGE PARK DEPT OF ELECTRICAL ENGINEERING
Personal Author(s) : Ho, Ping-Tong
PDF Url : ADA304993
Report Date : JAN 1996
Pagination or Media Count : 38
Abstract : A radio frequency (RF) antenna was demonstrated by exciting charge carriers in a semiconductor. Using a common camera flash and a custom mask, portions of a four inch diameter silicon wafer were illuminated to form a temporary electrically conductive pathway. The conductive path would momentarily mimic a thin layer metallic antenna through which RF energy could be received or transmitted. Experiments in the 1-4 GHz range showed the optically excited semiconductor antennas to be about 5 dB less efficient than similar dipole and bow-tie design metallic antennas. The silicon used had a carrier lifetime of approximately five microseconds when illuminated with an optical intensity of 1O watts per square centimeter. Changing illumination masks would allow the semiconductor antenna to be reconfigured to a variety of different antenna designs.
Descriptors : *DIPOLE ANTENNAS, CONDUCTIVITY, LAYERS, CHARGE CARRIERS, SEMICONDUCTORS, ILLUMINATION, SILICON, THINNESS, WAFERS, RADIOFREQUENCY, MASKS.
Subject Categories : Electrical and Electronic Equipment
Electricity and Magnetism
Distribution Statement : APPROVED FOR PUBLIC RELEASE