James L Crowley

Address:

14515 Tralee Pl, Chester, VA 23836

VIN:

WVWMP7AN2CE547911

Make:

VOLKSWAGEN

Model:

CC

Year:

2012

US Patent:

41819047, Jan 1, 1980

Filed:

Aug 9, 1978

Appl. No.:

5/932248

Inventors:

Joseph F. Weller - Oxon Hill MD
James D. Crowley - Menlo Park CA
Thomas G. Giallorenzi - Springfield VA

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

H03H 926
H03H 930
H03K 5159
H01L 4108

US Classification:

333153

Abstract:

Two input transducers launch oppositely-propagating acoustic surface waves on a piezoelectric substrate. The waves are compressed to a smaller beamwidth and then laterally confined in a diffused channel waveguide where non-linear interaction occurs at increased energy densities due to the beam compression. In one embodiment the beam compression is accomplished in multistrip couplers. In another embodiment, diffused horn-shaped channels are provided for compressing the beamwidth. Both piezoelectric and semiconductor convolvers are disclosed.

US Patent:

40889696, May 9, 1978

Filed:

Apr 19, 1977

Appl. No.:

5/788874

Inventors:

James D. Crowley - Oxon Hill MD
Joseph F. Weller - Oxon Hill MD
Thomas G. Giallorenzi - Springfield VA

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

H03H 930
H03F 304
H01L 4502
H03F 355

US Classification:

333 30R

Abstract:

A tapped surface acoustic wave (SAW) delay line with time-resolved outputs sing piezoelectric leaky wave coupling and bulk wave amplification, and having low loss characteristics. A solid piezoelectric semiconductor is placed adjacent to a solid piezoelectric substrate. A pulsed rf input signal is applied to interdigital transducers (IDT) on the substrate. The applied signal launches a SAW in the substrate in a direction parallel to the interface between the substrate and the piezoelectric semiconductor solid. Upon reaching the interface, the SAW is piezoelectrically leaky-wave coupled across an air gap to a bulk acoustic wave in the piezoelectric semiconductor. Reflections of the bulk wave occur at both surfaces of the piezoelectric semiconductor, and piezoelectrically couples back across the air gap to excite a SAW on the piezoelectric substrate. The resultant rf output includes the normal delayed SAW pulse and additional delayed and time-resolved pulses. The amplitude of the bulk wave may be increased using bulk wave amplification.