Douglas Scott Berger

US Patent:

57582637, May 26, 1998

Filed:

Dec 7, 1995

Appl. No.:

8/568871

Inventors:

Douglas M. Berger - Mission Viejo CA
John S. Walley - Lake Forest CA

Assignee:

Rockwell International Corporation - Newport Beach CA

International Classification:

H04B 1700

US Classification:

455 674

Abstract:

A method for testing a communication link between first and second components of a system, which components communicate via a selected one of a plurality of broadcast channels, the second component being powered by a self-contained power source, the method comprising: causing the first component to scan a plurality of the broadcast channels in sequence in a receiving mode during a scanning period and to broadcast a test signal over the selected channel during the scan; and maintaining the second component in an inactive state in which energy consumption is minimized and in which the second component is unresponsive to broadcast signals during a major part of the scanning period, placing the second component in an active state in which the second component can detect the test signal during a time when the test signal is being broadcast, and causing the second component to broadcast a response signal upon detection of the test signal.

US Patent:

55264212, Jun 11, 1996

Filed:

Feb 16, 1993

Appl. No.:

8/018277

Inventors:

Douglas L. Berger - Dallas TX
Donald G. Jones - Vernon TX

International Classification:

H04B 1500

US Classification:

379389

Abstract:

A voice transmission system including a microphone (13) in combination with active sound cancellation means comprising a speaker (14) and a signal processor (17) for generating a mirror-image waveform with respect to the signal generated when speaking into the microphone. The mirror-image waveform is used to activate the speaker (14) thereby cancelling the user's voice. This provides the user with complete privacy, since the cancellation prevents the user's voice from being overheard by others, even in a crowded area.