Eric J Funk

US Patent:

6640084, Oct 28, 2003

Filed:

Nov 29, 2000

Appl. No.:

09/725240

Inventors:

Krishna Pande - Gaithersburg MD 20878
Guobao Zheng - Oakhill VA 20171
Tho Nguyen - Chantilly VA 20151
Lee Phelps - Frederick MD 21702
Ali I. Bawangaonwala - Germantown MD 20874
Sunil M. Nagabhushana - Centreville VA 20121
Eric Funk - Annapolis MD 21401

International Classification:

H04H 100

US Classification:

455 301, 455 76, 455 81, 361688, 361704

Abstract:

The complete outdoor radio unit for LMDS is a light weight, compact transceiver featuring planar circuitry. The transceiver uses cross polarization through an orthomodal transducer and frequency offset between transmit and receive to provide isolation between the transmitter and receiver. The transceiver includes three printed circuit boards directly attached by thermally conductive epoxy to a heat sink which forms part of the antenna dish/transceiver housing for effective heat transfer. Two of the waveguides are used as receiver and transmitter transmission lines into the orthomodal transducer, and two of the waveguides are used as bandpass filters. The transceiver also includes a DCâDC converter in the power supply which is modified to connect the base plate to the heat sink for compactness and improved heat transfer, and a frequency synthesizer with a phase locked loop hardwired to a single reference frequency for compact size.

US Patent:

55964389, Jan 21, 1997

Filed:

Sep 21, 1995

Appl. No.:

8/530398

Inventors:

Stephen E. Saddow - Laurel MD
Eric Funk - Silver Spring MD
Louis J. Jasper - Fulton MD
Chi H. Lee - Potomac MD

Assignee:

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

International Classification:

H04B 1000
H04B 1500
H04K 100

US Classification:

359154

Abstract:

A photoconductive spread-spectrum communications system that includes a tsmitter and a receiver. The transmitter includes an oscillating laser, a Pockels' cell, a delay cell, a photoconductive switch, and an antenna for transmitting an electromagnetic spread-spectrum signal. The receiver includes an oscillating laser, a Pockels' cell, an antenna for receiving a spread-spectrum signal, a photoconductive switch, a filter, and a threshold detector for regenerating the signal contained within the spread-spectrum transmission.