1
Piu Bill Wong, Shimon B Scherzer, Ravi Narasimhan: Simultaneous forward link beam forming and learning method for mobile high rate data traffic. Metawave Communications Corporation, Fulbright & Jaworski L, December 11, 2001: US06330460 (109 worldwide citation)

Disclosed is a base station of a wireless communications system including an adaptive antenna array and beam forming means for forming simultaneous multiple forward link beams. Preferably mobile stations are separated into groups of mobile stations corresponding to a maximum number of simultaneous f ...


2
Ravi Narasimhan, Piu Bill Wong, Shimon B Scherzer, Jiangfeng Wu: Space-time and space-frequency hopping for capacity enhancement of mobile data systems. Kathrein Werke KG, Fulbright & Jaworski, March 21, 2006: US07016649 (60 worldwide citation)

The present invention utilizes adaptive antenna arrays at a base station to increase the forward link capacity of mobile data systems. One or more simultaneous forward link beams are formed and are switched (or hopped) in a time division manner among subscribers. The beam hopping sequence is randomi ...


3
Ravi Narasimhan: Method and apparatus for acquistion and tracking of orthogonal frequency division multiplexing symbol timing, carrier frequency offset and phase noise. Marvell International, May 12, 2009: US07532693 (37 worldwide citation)

A method for estimating symbol timing of a guard interval in an orthogonal frequency division multiplexing receiver of a wireless local area network comprises receiving a preamble including a plurality of short training symbols; sampling said short training symbols of said preamble at a first rate; ...


4
Ravi Narasimhan: Multicarrier transmit diversity. Marvell International, August 18, 2009: US07577085 (34 worldwide citation)

Method, apparatus, and data packet format to implement transmit diversity in a multicarrier environment is disclosed. For diversity transmission operations, space frequency encoding techniques are employed creating distinguishable first and second time domain signals from a multicarrier frequency do ...


5
Ravi Narasimhan: Apparatus and method for measuring signal quality of a wireless communications link. Marvell International, March 21, 2006: US07016651 (33 worldwide citation)

Techniques for measuring signal quality in a communications link supporting OFDM symbol transfer across plural sub-carriers are disclosed. These techniques employ a link interface receiving OFDM symbol(s) from the link, and a signal-to-noise ratio (SNR) estimation unit generating an estimate of a ge ...


6
Ravi Narasimhan, Hemanth Sampath, Hsiao Cheng Tang: MIMO-OFDM receiver processing with frequency and channel estimation. Marvell International, August 5, 2008: US07408976 (32 worldwide citation)

A receiver in a MIMO-OFDM system may process OFDM symbols received on a number (MR) of receive antennas. The system may utilize a MIMO-OFDM frame format that includes additional long training OFDM symbols, for training additional antennas and for link adaptation, and a header with an additional SIGN ...


7
Ravi Narasimhan, Donald C Cox: Method for handoff in wireless communication systems using pattern recognition. The Board of Trustees of the Leland Stamford Junior University, Lumen IPS, May 29, 2001: US06240291 (30 worldwide citation)

A handoff technique for wireless communication systems uses pattern recognition of signal strength data to anticipate handoffs and reduce the total number of handoffs in the system. A criterion for system performance is used in determining the necessity for handoff. A window of signal samples from n ...


8
Hongche Liu, Ravi Narasimhan Raj: Canonicalization of terms in a keyword-based presentation system. Yahoo, Hickman Palermo Truong & Becker, February 28, 2006: US07007014 (29 worldwide citation)

A presentation system accepts presentations or references to presentations from prospective presenters, some or all of which are stored in a database and referenced by keywords such that presentations to be presented in response to particular searches can be identified. A presentation manager handle ...


9
Ravi Narasimhan: Method and apparatus for estimation of orthogonal frequency division multiplexing symbol timing and carrier frequency offset. Marvell International, May 15, 2007: US07218691 (26 worldwide citation)

A system and method estimates symbol timing of long training symbols and coarse carrier frequency offset in an orthogonal frequency division multiplexing receiver of a wireless local area network. The system and method estimates the symbol timing and coarse carrier frequency offset during short trai ...


10
Atul Salhotra, Ravi Narasimhan, Rahul Kopikare: Circuits, architectures, systems, methods, algorithms and software for reducing contention and/or handling channel access in a network. Marvell International, November 2, 2010: US07826438 (26 worldwide citation)

Methods, circuits and architectures for managing channel access and/or reducing contention in network transmissions where such transmissions may not be acknowledged within a certain time period, computer programs adapted to implement such methods, and systems and networks including such circuits/arc ...