Accession Number : ADA289579

Title :   An Optoelectronic Attenuator for the High-Speed Control of Microwave Integrated Circuits.

Descriptive Note : Final rept. Nov 90-Dec 93,

Corporate Author : ARMY RESEARCH LAB ADELPHI MD

Personal Author(s) : Saddow, Stephen E. ; Lee, Chi H.

PDF Url : ADA289579

Report Date : NOV 1994

Pagination or Media Count : 83

Abstract : An optoelectronic attenuator suitable for the optical control of microwave integrated circuits is presented. High-speed photoconductive switches are embedded in planar microwave transmission lines, and semiconductor laser diodes (LDs) are used to control the microwave signal level on these high-speed lines. With a silicon coplanar waveguide-photoconductive switch (Si:CPW-PCS), up to 45 dB of microwave attenuation has been achieved with a fiber-pigtailed laser diode having 144 mW of optical power. Measurements made using a vector network analyzer show that the attenuator performance can be explained by a classical plasma absorption argument, whereby the microwave signal is attenuated by the optically induced solid-state plasma. Edge-coupled Fabry-Perot aluminum-gallium-arsenide/gallium-arsenide (AlGaAs/GaAs) semiconductor LDs, as well as both silicon and gallium-arsenide (GaAs) CPW-PCSs, were developed for the optoelectronic attenuator. When conventional gain-switching techniques are used, LD peak Output powers greater than 1 W have been demonstrated, and when an optical Q-switching scheme is used, 6 W of peak power has been achieved in tens of picoseconds. (jg)

Descriptors :   *OPTICAL PROPERTIES, *INTEGRATED CIRCUITS, *MICROWAVES, *ELECTRIC SWITCHES, *ATTENUATORS, DIODES, Q SWITCHING, OUTPUT, CONTROL, ELECTROOPTICS, NETWORKS, PLASMAS(PHYSICS), GALLIUM ARSENIDES, ALUMINUM GALLIUM ARSENIDES, SEMICONDUCTOR LASERS, TRANSMISSION LINES, MICROWAVE EQUIPMENT, SEMICONDUCTOR DIODES, LASERS, OPTICAL WAVEGUIDES, PEAK POWER, SIGNALS, SILICON, PLANAR STRUCTURES, VECTOR ANALYSIS, ATTENUATION, POWER, ABSORPTION, ANALYZERS, PHOTOCONDUCTIVITY, MICROWAVE TRANSMISSION.

Subject Categories : Inorganic Chemistry
      Electrical and Electronic Equipment
      Fluid Mechanics
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE