Sina S Barkeshli

US Patent:

60493127, Apr 11, 2000

Filed:

Feb 11, 1998

Appl. No.:

9/021926

Inventors:

Peter Lord - Mountain View CA
Howard Luh - Sunnyvale CA
Sina Barkeshli - Saratoga CA
Louis B. Brydon - San Carlos CA
Jeff Zaine - Pleasanton CA

Assignee:

Space Systems/Loral, Inc. - Palo Alto CA

International Classification:

H01Q 1914

US Classification:

343781P

Abstract:

An antenna system having a front reflector and a rear reflector arranged in tandem, a front feed for illuminating the front reflector, and a rear feed for illuminating the rear reflector. Each of the reflectors has a generally dish-shaped configuration, and the feeds are located in positions offset from axes of the respective reflectors. The front reflector is reflective to a first radiation, while being substantially transparent to a second radiation except for a fraction of the power of the second radiation. The fractional part of the second radiation is reflected from the first reflector as an interfering beam, the interfering beam being scanned away from a coverage region of a beam of the first radiation by an offset between the feeds. The radiations may differ in polarization or in frequency. There may be a complete shading of the rear reflector by the front reflector from the radiation of the rear feed to produce uniform illumination of the rear reflector for greater accuracy in a formation of a beam from the rear reflector.

US Patent:

54712246, Nov 28, 1995

Filed:

Nov 12, 1993

Appl. No.:

8/151501

Inventors:

Sina Barkeshli - Saratoga CA

Assignee:

Space Systems/Loral Inc. - Palo Alto CA

International Classification:

H01Q 1502
H01Q 1524

US Classification:

343909

Abstract:

A microwave element having a frequency selective surface (FSS) is formed of a substantially planar substrate of dielectric material which is transparent to electromagnetic radiation, and supports an array of radiators wherein the radiators are arranged in a plurality of sets of radiators. In each set of radiators, in a preferred embodiment, there are three concentric radiators fabricated of an electrically conductive material. The outermost radiator has a hexagonal closed form, and the inner radiators are configured as circular annuluses. In each set, the largest radiator has a circumference equal to a wavelength of a first frequency of radiation to be reflected from the (FSS), the sets being spaced apart by a spacing equal to one-third of the foregoing wavelength in the dielectric substrate. In a two-dimensional array of the sets of the radiators, the sets are located at vertices of equilateral triangles. An antenna incorporating the FSS includes a first horn operative at radiation of the foregoing wavelength and a reflector, both of which are disposed on one side of the FSS.

US Patent:

55572928, Sep 17, 1996

Filed:

Jun 22, 1994

Appl. No.:

8/263558

Inventors:

Evert C. Nygren - Los Altos CA
Peter W. Lord - Mountainview CA
Vito J. Jakstys - Penn Valley CA
Sina Barkeshli - Saratoga CA
Levent Ersoy - Cupertino CA

Assignee:

Space Systems/Loral, Inc. - Palo Alto CA

International Classification:

H01Q 1914

US Classification:

343781P

Abstract:

An antenna has one feed for an S-band electromagnetic signal, and a second feed constructed as an array of radiators to service two C-band signal channels. A subreflector having a microwave frequency selective surface (FSS) is placed in front of a main reflector. The C-band feed is constructed of an array of square aperture horns joined by separate transmit and receive barline beam-forming networks, and a meanderline polarizer to produce circularly polarized radiation patterns. Tapered ridges extend longitudinally along inner wall surfaces of each of the horns to provide increased bandwidth to the C-band feed. The frequency selective surface is constructed, typically, of a generally planar substrate of material transparent to electromagnetic radiation, and numerous metallic, generally annular, radiating elements, or resonators, arranged on the substrate in an array of repeating nested sets of the radiating elements. The lower frequency S-band feed is located behind and to the side of the subreflector for transmission of radiation via a folded optical path to the main reflector. The C-band feed is located in front of and to the side of the subreflector for transmission of radiation along a straight path through the FSS to the main reflector.

US Patent:

20220247603, Aug 4, 2022

Filed:

Jan 31, 2022

Appl. No.:

17/589325

Inventors:

- Singapore, SG
Sina Barkeshli - Saratoga CA, US

International Classification:

H04L 25/03
H04L 5/00
H04L 5/14

Abstract:

During a training procedure for communicating via a full-duplex communication link, a first communication device receives training information from a second communication device. The training information corresponds to first signal processing parameters developed at the second communication device for use by the second communication device to process signals received by the second communication device via the full-duplex communication link. After receiving the training information from the second communication device, the first communication device develops second signal processing parameters to be used by the first communication device to process signals received by the first communication device via the full-duplex communication link. The second signal processing parameters are developed using the training information received from the second communication device.

US Patent:

20150124891, May 7, 2015

Filed:

May 7, 2012

Appl. No.:

14/399151

Inventors:

Mithat Dogan - San Jose CA, US
John M. Cioffi - Atherton CA, US
Mark B. Flowers - Los Gatos CA, US
Sina Barkeshli - Saratoga CA, US

Assignee:

ADAPTIVE SPECTRUM AND SIGNAL ALIGNMENT, INC. - Redwood City CA

International Classification:

H04L 1/00
H04M 3/00
H04M 3/22
H04L 1/20

US Classification:

375257

Abstract:

In accordance with embodiments disclosed herein, there are provided apparatus, systems and methods for impulse noise detection and mitigation. For example, in one embodiment such means include, means for detecting impulse noise; means for classifying the detected impulse noise into one of a plurality of impulse noise classes affecting communications on a Digital Subscriber Line (DSL line); means for selecting a noise mitigation strategy from among a plurality of noise mitigation strategies; means for applying the selected noise mitigation strategy; and means for validating application of the noise mitigation strategy.