James Daniel Dyer

US Patent:

46302859, Dec 16, 1986

Filed:

Mar 18, 1985

Appl. No.:

6/712934

Inventors:

James W. Dyer - Laurel MD
Raymond R. Watkins - Ellicott City MD

Assignee:

The United States of America as represented by the Director of the
National Security Agency - Washington DC

International Classification:

H04L 2700

US Classification:

375 37

Abstract:

A method is disclosed for eliminating group delay distortion resulting from filtering an information-carrying analog signal. The method allows an analog signal to be converted to digital form and back again with zero group delay distortion. The analog signal is first band or low pass filtered with a filter having a pass band substantially larger than that required to filter only the signal of interest. The filtered signal is then digitized at a rate appropriate to the filtered signal, digitally filtered to remove all but the signal of interest, and down sampled to the transmission rate. A substantially reversed process is described for reconverting the digital signal to analog form. The method is shown to be equally effective with a multiplexed signal.

US Patent:

20120216288, Aug 23, 2012

Filed:

May 14, 2010

Appl. No.:

13/320411

Inventors:

Victor I. Sheymov - Vienna VA, US
Jan Willem Valentijn Kerseboom - Amsterdam, NL
James W. Dyer - Port St. Lucie FL, US
Jean Dyer - Port St. Lucie FL, US

Assignee:

INVICTA NETWORKS, INC. - Reston VA

International Classification:

G06F 21/00

US Classification:

726 26

Abstract:

A method, system, and computer program product for secure distribution of content over an insecure medium, including a recipient device configured to receive content; and a sender device configured to request from the recipient device a unique identification associated with the recipient device, before sending to the recipient device, the content and a unique key associated with the content for use of the content by the recipient device. The sender device is configured to request the unique identification associated with the recipient device from the recipient device during a predetermined time interval after sending the key, and after verification of the unique identification, send a new key associated with the content to the recipient device for further use of the content by the recipient device.