Srinivas Kandala

US Patent:

6505037, Jan 7, 2003

Filed:

Feb 23, 2000

Appl. No.:

09/510907

Inventors:

Srinivas Kandala - Vancouver WA

Assignee:

SHARP Laboratories of America, Inc. - Camas WA

International Classification:

H04Q 700

US Classification:

4552772, 4552321, 4552451

Abstract:

A system adjusts a receiving device in response to sensing symbols. An automatic gain control is adjusted in response receiving a first symbol of a data unit from a first antenna. After adjusting the automatic gain control at least a second and a third symbol of the data unit are received, and in response thereto (1) a first energy of at least one of the second and third symbols is calculated, (2) a first frequency offset of at least one of the second and third symbols is calculated, and (3) a first temporal offset of at least one of the second and third symbols is calculated. The automatic gain control in response receiving a fourth symbol of the data unit from a second antenna is received. After adjusting the automatic gain control at least a fifth and a sixth symbol of the data unit is calculated, and in response thereto (1) a second energy of at least one of the fifth and sixth symbols is calculated, (2) a second frequency offset of at least one of the fifth and sixth symbols is calculated, and (3) a second temporal offset of at least one of the fifth and sixth symbols is calculated. At least one of the first and second antenna is selected based upon a comparison between the first and second energy.

US Patent:

7519035, Apr 14, 2009

Filed:

Feb 1, 2005

Appl. No.:

11/050487

Inventors:

John M. Kowalski - Camas WA,
Srinivas Kandala - Vancouver WA,

Assignee:

Sharp Laboratories of America, Inc. - Camas WA

International Classification:

H04Q 7/24

US Classification:

370338, 370329

Abstract:

A method of selectively providing MIMO transmission/reception in a WLAN system includes using a TSPEC reservation and signaling mechanism to instantiate and tear down, dynamically, multi-channel operation in a WLAN; providing an inference algorithm to determine the minimum number of channels required to establish a TSPEC using a MIMO WLAN system; providing specific channel parameters as parameters to be negotiated in the TSPEC; providing frame exchange sequences to be used in Enhanced Distributed Coordinated Access contention based access and to be used in polled access; and providing a mechanism wherein an access point makes a decision as to whether to admit MIMO functionality on a given link, wherein a “link” is a set of communications between two specific WLAN stations.

US Patent:

62086324, Mar 27, 2001

Filed:

Jan 29, 1998

Appl. No.:

9/015424

Inventors:

John M. Kowalski - Vancouver WA
Srinivas Kandala - Vancouver WA
V. Srinivasa Somayazulu - Tigard OR

Assignee:

Sharp Laboratories of America - Camas WA

International Classification:

H04B7/216

US Classification:

370335

Abstract:

A wideband CDMA receiver system to accept messages from asynchronously transmitting base stations is provided. The base station transmission to each receiver includes a perch channel and at least one traffic channel. Although all the channels typically include pilot symbols for the purpose of demodulating the information symbols of the channel, the pilot channel includes a higher proportion of pilot symbols to information symbols. Therefore, a perch channel based timing and estimation system is inherently more accurate. In addition, the perch channel is generally transmitted at higher power levels than a traffic channel, and the resulting, higher, signal to noise ratio signal also improves the accuracy of the timing and channel estimation. Based on the timing derived from the perch channel of a first base station, the receiver can set the timing of the traffic channel transmissions from a second base station, to more closely match the timing of traffic channel transmissions from the first base station. In this manner, the signal to noise ratio of the demodulated traffic channel information symbols is enhanced through the diversity of using the transmissions of two base stations.

US Patent:

6085104, Jul 4, 2000

Filed:

Mar 25, 1998

Appl. No.:

9/048240

Inventors:

John M. Kowalski - Vancouver WA
Srinivas Kandala - Vancouver WA
V. Srinivasa Somayazulu - Tigard OR

Assignee:

Sharp Laboratories of America, Inc. - Camas WA

International Classification:

H04B 1500

US Classification:

455506

Abstract:

A wideband receiver, including a time-varying finite impulse response (FIR) filter, has been provided to combine multipath communications of data in response to pilot channel timing information. The time-varying FIR processes the multipath communications through independent signal paths. Each signal path includes a variable delay circuit and a variable gain circuit. The delay of each separate signal path is adjusted and made equal in response to the pilot channel timing information. Likewise, the gain of each signal path is adjusted in response to pilot channel gain information to maximize the signal to noise ratio of the combined signal paths. The separate signal paths are then summed in a combiner circuit. The time-varying FIR permits the data communication to be summed either before, or after demodulation. A method of combining multipath communications using a time-varying FIR is also provided.

US Patent:

20090252143, Oct 8, 2009

Filed:

Nov 25, 2008

Appl. No.:

12/277770

Inventors:

Vinay Sridhara - Santa Clara CA,
Sanjiv Nanda - Ramona CA,
Srinivas Kandala - San Jose CA,

Assignee:

QUALCOMM Incorporated - San Diego CA

International Classification:

H04J 3/00

US Classification:

370345

Abstract:

Methods and apparatus for delayed block acknowledgments in a WLAN. In an aspect, a method is provided for communication with one or more nodes. The method includes transmitting to the one or more nodes a block comprising data and a first bit indicating no acknowledgements for the data are to be transmitted from the one or more nodes. The method also includes determining whether a selected time location within a transmit time duration has been reached, wherein if the selected time location has been reached, transmitting to the one or more nodes a second bit indicating that the one or more nodes are to transmit one or more acknowledgements, respectively, for the data. The method also includes receiving at least one acknowledgment for the data within a remaining portion of the transmit time duration.

US Patent:

20090252110, Oct 8, 2009

Filed:

Jan 29, 2009

Appl. No.:

12/361773

Inventors:

Vinay Sridhara - Santa Clara CA,
Sanjiv Nanda - Ramona CA,
Santosh P. Abraham - San Diego CA,
Srinivas Kandala - San Jose CA,

Assignee:

QUALCOMM Incorporated - San Diego CA

International Classification:

H04J 3/00
H04J 1/00
H04W 84/12

US Classification:

370330, 370336, 370338

Abstract:

Methods and apparatus for extended reverse direction grant in a WLAN. In an aspect, a method includes transmitting data within a transmit interval to a plurality of the nodes, wherein the data comprises a first indicator. The method also includes receiving, in response to the first indicator, a data transmission from at least one of the nodes, wherein the data transmission was transmitted using a selected transmission resource and is received within the transmit interval. In an aspect, an apparatus includes a receiver to receive, within a time interval, first data over a common channel, the first data being decodable by other nodes. The apparatus also includes a controller to determine whether the first data comprises a first indicator, and a transmitter to transmit second data within the time interval using selected transmission resources, if the first data comprises the first indicator.

US Patent:

20020159418, Oct 31, 2002

Filed:

Feb 28, 2001

Appl. No.:

09/795539

Inventors:

William Rudnick - Beaverton OR,
John Kowalski - Vancouver WA,
Srinivas Kandala - Vancouver WA,

Assignee:

Sharp Laboratories of America, Inc.

International Classification:

H04J003/16

US Classification:

370/338000, 370/346000

Abstract:

A method of providing Quality of Service (QoS) in a wireless LAN system, wherein plural stations comprise the wireless LAN network, and wherein the wireless LAN network includes a protocol providing for contention periods and contention free periods, includes grouping the stations into a polling list set; selecting a number of the grouped stations for inclusion in a polling list subset, wherein preference is given to high-priority QoS stations in the polling list subset; and polling the high priority stations during a contention free period.

US Patent:

20020141376, Oct 3, 2002

Filed:

Mar 30, 2001

Appl. No.:

09/822679

Inventors:

Srinivas Kandala - Vancouver WA,

Assignee:

Sharp Labs of America - Camas WA

International Classification:

H04J003/02

US Classification:

370/348000, 370/462000

Abstract:

Devices, softwares and methods for wireless devices to form a network on the fly by performing admission control while in the second layer, without going to the third layer. A peripheral station encodes a priority of data in a tag that is transmitted in a reservation request frame. A cooperating complementary access point receives the reservation request frame and reads the tag. The request is finally resolved (granted or denied) at the second level, using the priority information of the tag.