Sanjay Kumar Gupta

US Patent:

20100259752, Oct 14, 2010

Filed:

Apr 12, 2010

Appl. No.:

12/758673

Inventors:

Tushar K. Shah - Columbia MD, US
John J. Morber - Taneytown MD, US
Pierre Kabro - Perry Hall MD, US
Sanjay Gupta - La Jolla CA, US

Assignee:

LOCKHEED MARTIN CORPORATION - Bethesda MD

International Classification:

G01J 3/00
H01L 31/0232
G02B 6/00

US Classification:

356300, 25022718, 385 12, 977742, 977954, 977957

Abstract:

Systems and methods for sensing an external measurand are disclosed. A sensor includes an optical fiber having at least one fiber Bragg grating (FBG) section and a plurality of carbon nanotubes (CNTs) surrounding at least a portion of the FBG section. Light is provided into the sensor while the CNTs are exposed to one or more measurands. A change in a spectrum of one of a transmitted portion and a reflected portion of the light is determined. A measurand that has caused the change is identified.

US Patent:

57937559, Aug 11, 1998

Filed:

Jul 7, 1995

Appl. No.:

8/499421

Inventors:

Prabhat K. Gupta - Germantown MD
Sanjay Gupta - Germantown MD
Paul Gaske - Rockville MD
Bob Kepley - Gaithersburg MD

Assignee:

Hughes Electronics Corporation - El Segundo CA

International Classification:

H04B 320

US Classification:

370286

Abstract:

A signal classifier and a echo suppressor for a facsimile calls in an echo prone network. The signal classifier quickly and reliably differentiates facsimile calls from voice and modem calls. The echo suppressor suppresses echo and has a variable hangover time which avoids attenuating and distorting a return transmission signal.

US Patent:

56490127, Jul 15, 1997

Filed:

Sep 15, 1995

Appl. No.:

8/529042

Inventors:

Prabhat K. Gupta - Germantown MD
Sanjay Gupta - Germantown MD

Assignee:

Hughes Electronics - Los Angeles CA

International Classification:

H04B 323

US Classification:

379410

Abstract:

A method of synthesizing an echo path in an echo canceller is provided. The method includes the steps of obtaining near end and far end signal samples at an echo canceller, locating the echo in a background task using a whitened version of the signal, transferring the echo location information to a foreground task, and eliminating the echo in the incoming signals by filtering the signal in the location passed to the foreground task by the background task.

US Patent:

58094636, Sep 15, 1998

Filed:

Sep 15, 1995

Appl. No.:

8/528967

Inventors:

Sanjay Gupta - Germantown MD
Prabhat K. Gupta - Germantown MD

Assignee:

Hughes Electronics - Los Angeles CA

International Classification:

G10L 900

US Classification:

704233

Abstract:

A method of detecting double talk in an echo canceller is provided. The method includes determining far end, near end and echo signal cancelled power, determining the presence of near end, maybe near end and far end speech, and controlling an echo suppressor and filter coefficient updates in an echo canceller.

US Patent:

56895569, Nov 18, 1997

Filed:

Sep 15, 1995

Appl. No.:

8/528762

Inventors:

Prabhat K. Gupta - Germantown MD
Sanjay Gupta - Germantown MD

Assignee:

Hughes Electronics - Los Angles CA

International Classification:

H04B 323

US Classification:

379410

Abstract:

A method of detecting narrow-band signals in an echo canceller to control the coefficient update process, echo suppression process, and the disablement of the echo canceller is provided. The method includes the steps of searching for the presence of a generic tone, searching for DTMF tones, searching for a 2100 Hz tone and, if a generic tone is found, searching for a dial tone. If a generic tone is detected on the far end signal, a tone flag is set which triggers the disablement of the echo canceller coefficient update process and the enablement of the echo suppressor process. If a 2100 Hz tone is detected, the echo canceller is disabled. If a DTMF signal is detected, DTMF flags are set which are used by the echo suppressor for suppressing the near end echo. Finally, if a dial tone is detected, dial tone flags are set which cause the disablement of the echo suppressor.

US Patent:

59498889, Sep 7, 1999

Filed:

Sep 15, 1995

Appl. No.:

8/529232

Inventors:

Sanjay Gupta - Germantown MD
Prabhat K. Gupta - Germantown MD
Bob Kepley - Gaithersburg MD

Assignee:

Hughes Electronics Corporaton - El Segundo CA

International Classification:

H04B 320

US Classification:

381 66

Abstract:

The invention describes a method and device of comfort noise generation for echo cancelers. The invention stores the actual background noise of a channel in a noise buffer. When the echo suppressor is activated by the echo canceler to suppress any unwanted signals on the channel, the buffer provides the stored noise to the channel to provide continuous background noise. To ensure that neither speech nor impulse noise enters the buffer, hangover delays and energy threshold levels are provided such that signals within the delay period or signals which exceed the energy threshold level are screened from entering the buffer.

US Patent:

20140100178, Apr 10, 2014

Filed:

Oct 4, 2012

Appl. No.:

13/645436

Inventors:

Aslam Ansari - Gaithersburg MD, US
Sanjay Gupta - Woodbridge VA, US

International Classification:

A61K 47/48

US Classification:

514 27, 536 174

Abstract:

A system for selectively delivering drugs to target tissues is provided. The system includes a drug-linker-saccharide-drug conjugate (D-L-A-D1). The linker includes a functional group that is recognized and cleaved by enzyme in the target phases. The recognition segment is preferably a malaria drugs. The carrier is preferably hydrophilic, biodegradable and biocompatible particle. Any drug may be delivered using a conjugate prepared according to the invention.