Accession Number:

ADA008967

Title:

An Investigation of the Frequency Limitations of a Surface Wave Variable Delay Line.

Descriptive Note:

Technical memo.,

Corporate Author:

HARRY DIAMOND LABS ADELPHI MD

Personal Author(s):

• Hopp,Theodore H.

Report Date:

1974-12-01

Pagination or Media Count:

18.0

Abstract:

An acoustic surface wave, variable delay line was invented at HDL. It consists of a fixed interdigital source transducer formed by metal deposited on a piezoelectric, photoconductive surface. The receiving transducer is formed by illuminating the photoconductive surface through a mask to create the image of a transducer where the signal is to be received. By making the optics movable, a variable path length and, hence, a variable delay time can be achieved. This paper derives a limit on the maximum usable frequency of such a device and proposes some modifications to the invention which will increase this upper frequency limit. The feasibility of the systems described herein have not been experimentally investigated, but they all seem to have merit. A continuously variable acoustic surface wave delay line operating at 1 GHz appears to be feasible.

Descriptors:

• *SEMICONDUCTOR DEVICES
• *ELECTROACOUSTIC TRANSDUCERS
• *ACOUSTIC DELAY LINES
• GALLIUM ARSENIDES
• ZINC SULFIDES
• SUBSTRATES
• PIEZOELECTRIC CRYSTALS
• INDIUM ANTIMONIDES
• CADMIUM SULFIDES

Subject Categories:

• Electrical and Electronic Equipment

Distribution Statement:

APPROVED FOR PUBLIC RELEASE