Patents by Inventor Badri Varadarajan
Badri Varadarajan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20120257639Abstract: Systems and methods for designing, using, and/or implementing communications in beacon-enabled networks are described. In various implementations, these systems and methods may be applicable to power line communications (PLC). For example, a method may include identifying one of a plurality of orthogonal superframes. The identified superframe may include beacon slots and contention access period (CAP) slots. The beacon slots may follow a sequence of two or more frequency subbands, and the CAP slots may follow the same sequence of two or more frequency subbands. Also, the sequence of two or more frequency subbands may be distinct from other sequences of two or more frequency subbands followed by other beacon slots and CAP slots within others of the plurality of available superframes. The method may then include communicating with another device using the identified superframe.Type: ApplicationFiled: March 30, 2012Publication date: October 11, 2012Applicant: TEXAS INSTRUMENTS INCORPORATEDInventors: Kumaran Vijayasankar, Shu Du, Anand Dabak, Badri Varadarajan, Il Han Kim, Xiaolin Lu
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Patent number: 8259824Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter is for use with NT transmit antennas and includes a precoder unit configured to precode data for transmission using a preceding matrix selected from a nested codebook, wherein the nested codebook provides codebooks corresponding to different transmission layers that are derived from column subsets of multiple NT×NT preceding matrices. The transmitter also includes a transmit unit configured to transmit the precoded data. In another embodiment, the receiver includes a receive unit configured to receive preceded data. The receiver also includes a precoder selection unit configured to select a preceding matrix from a nested codebook for the preceded data, wherein the nested codebook provides codebooks corresponding to different transmission layers that are derived from column subsets of multiple NT×NT preceding matrices.Type: GrantFiled: May 21, 2008Date of Patent: September 4, 2012Assignee: Texas Instruments IncorporatedInventors: Badri Varadarajan, Eko N. Onggosanusi, Runhua Chen, Il H. Kim
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Publication number: 20120189126Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter includes a synchronization unit configured to provide a primary synchronization signal and a secondary synchronization signal having first and second segments. The transmitter also includes a secondary scrambling unit configured to provide a scrambled secondary synchronization signal, wherein scrambling agents for the first and second segments are derived from a primary synchronization sequence of the primary synchronization signal. The secondary scrambling unit is further configured to provide an additional scrambling of one of the first and second segments, wherein a second scrambling agent is derived from the remaining segment of a secondary synchronization sequence of the secondary synchronization signal.Type: ApplicationFiled: April 2, 2012Publication date: July 26, 2012Inventors: Anand G. Dabak, Eko N. Onggosanusi, Badri Varadarajan
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Patent number: 8175077Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter includes a synchronization unit configured to provide a primary synchronization signal and a secondary synchronization signal having first and second segments. The transmitter also includes a secondary scrambling unit configured to provide a scrambled secondary synchronization signal, wherein scrambling agents for the first and second segments are derived from a primary synchronization sequence of the primary synchronization signal. The secondary scrambling unit is further configured to provide an additional scrambling of one of the first and second segments, wherein a second scrambling agent is derived from the remaining segment of a secondary synchronization sequence of the secondary synchronization signal.Type: GrantFiled: September 22, 2011Date of Patent: May 8, 2012Assignee: Texas Instruments IncorporatedInventors: Anand G Dabak, Eko M Onggosanusi, Badri Varadarajan
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Publication number: 20120082253Abstract: A system and method for communicating in a power line communications (PLC) network using Orthogonal Frequency-Division Multiplexing (OFDM) symbols. Pilot tones are carried by the OFDM symbols according to a predetermined pattern. A receiving device identifies pilot tones on each frequency. A group of previously received pilot tones on a selected frequency are filtered to generate a channel estimate for a tone on the selected frequency in a new symbol. The channel estimates on two different frequencies within an OFDM symbol may be interpolated to determine a channel estimate for a third frequency with the OFDM symbol.Type: ApplicationFiled: July 1, 2011Publication date: April 5, 2012Applicant: TEXAS INSTRUMENTS INCORPORATEDInventors: Badri Varadarajan, Anand Dabak, Il Han Kim, Akula Aneesh Reddy
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Publication number: 20120068784Abstract: Coupling circuits for power line communication (PLC) devices are described. In an embodiment, a PLC device may comprise a processor and a coupling circuit coupled to the processor. The coupling circuit may in turn comprise a transmitter path and a receiver path. In some implementations, the transmitter path may include a first amplifier, a first capacitor coupled to the first amplifier, a first transformer coupled to the first capacitor, and a plurality of line interface coupling circuits coupled to the first transformer, where each of the line interface coupling circuits is configured to be connected to a different phase of an electrical power circuit. Meanwhile, the receiver path may include a plurality of capacitors, where each of the plurality of capacitors coupled to a corresponding one of the line interface circuits, a filter network coupled to the plurality of capacitors, and a second amplifier coupled to the filter network.Type: ApplicationFiled: September 9, 2011Publication date: March 22, 2012Applicant: TEXAS INSTRUMENTS INCORPORATEDInventors: Badri Varadarajan, Edward Mullins
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Publication number: 20120033722Abstract: Embodiments of the invention provide time-domain link adaptation in power line communications. In one embodiment, the cyclic prefix length and position is adjusted with an OFDM symbol to overlap a periodic impulse noise pulse, thereby allowing the data carried in the symbol to be detected at a receiver. The cyclic prefix may be adjusted to provide a pattern that yields an integer number of OFDM symbols in one zero crossing period. The data rate used for the symbols overlapping the zero-crossing period may be zero or very low. A high data rate may be used for symbols outside the zero-crossing period because those symbols will not be affected by the periodic impulse noise.Type: ApplicationFiled: July 8, 2011Publication date: February 9, 2012Applicant: TEXAS INSTRUMENTS INCORPORATEDInventors: Badri Varadarajan, Anand Dabak, Il Han Kim
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Publication number: 20120008710Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter includes a synchronization unit configured to provide a primary synchronization signal and a secondary synchronization signal having first and second segments. The transmitter also includes a secondary scrambling unit configured to provide a scrambled secondary synchronization signal, wherein scrambling agents for the first and second segments are derived from a primary synchronization sequence of the primary synchronization signal. The secondary scrambling unit is further configured to provide an additional scrambling of one of the first and second segments, wherein a second scrambling agent is derived from the remaining segment of a secondary synchronization sequence of the secondary synchronization signal.Type: ApplicationFiled: September 22, 2011Publication date: January 12, 2012Applicant: TEXAS INSTRUMENTS INCORPORATEDInventors: Anand G. Dabak, Eko N. Onggosanusi, Badri Varadarajan
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Patent number: 8054823Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter includes a synchronization unit configured to provide a primary synchronization signal and a secondary synchronization signal having first and second segments. The transmitter also includes a secondary scrambling unit configured to provide a scrambled secondary synchronization signal, wherein scrambling agents for the first and second segments are derived from a primary synchronization sequence of the primary synchronization signal. The secondary scrambling unit is further configured to provide an additional scrambling of one of the first and second segments, wherein a second scrambling agent is derived from the remaining segment of a secondary synchronization sequence of the secondary synchronization signal.Type: GrantFiled: June 17, 2008Date of Patent: November 8, 2011Assignee: Texas Instruments IncorporatedInventors: Anand G. Dabak, Eko N. Onggosanusi, Badri Varadarajan
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Publication number: 20110211662Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter has at least three transmit antennas and includes a feedback decoding portion configured to recover at least one group-based channel quality indicator provided by a feedback signal from a receiver, wherein each group-based channel quality indicator corresponds to one of a set of transmission layer groupings. The transmitter also includes a modulator portion configured to generate at least one symbol stream and a mapping portion configured to multiplex each symbol stream to at least one transmission layer grouping. The transmitter further includes a pre-coder portion configured to couple the transmission layers to the transmit antennas for a transmission. The receiver includes a decoder portion which is configured to use decoded signals from at least one group to decode the other groups.Type: ApplicationFiled: May 10, 2011Publication date: September 1, 2011Applicant: Texas Instruments IncorporatedInventors: Badri Varadarajan, Eko N. Onggosanusi
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Publication number: 20110182178Abstract: In at least some embodiments, a communication device includes a transceiver with Carrier Sensing Multiple Access with Collision Avoidance (CSMA-CA) logic. The CSMA-CA logic provides dynamic randomization management for a contention window size.Type: ApplicationFiled: January 19, 2011Publication date: July 28, 2011Applicant: TEXAS INSTRUMENTS INCORPORATEDInventors: Shu DU, Susan YIM, Xiaolin LU, Badri VARADARAJAN
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Patent number: 7961810Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter has at least three transmit antennas and includes a feedback decoding portion configured to recover at least one group-based channel quality indicator provided by a feedback signal from a receiver, wherein each group-based channel quality indicator corresponds to one of a set of transmission layer groupings. The transmitter also includes a modulator portion configured to generate at least one symbol stream and a mapping portion configured to multiplex each symbol stream to at least one transmission layer grouping. The transmitter further includes a pre-coder portion configured to couple the transmission layers to the transmit antennas for a transmission. The receiver includes a decoder portion which is configured to use decoded signals from at least one group to decode the other groups.Type: GrantFiled: September 7, 2007Date of Patent: June 14, 2011Assignee: Texas Instruments IncorporatedInventors: Badri Varadarajan, Eko N. Onggosanusi
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Patent number: 7961672Abstract: Embodiments of a feedback generator and decoder and methods of operating the feedback generator and decoder are presented. In one embodiment, the feedback generator includes a CQI compression module configured to provide a compressed CQI for the user equipment corresponding to at least one sub-band, where a sub-band is composed of at least one resource block. The feedback generator also includes a transmit module coupled to the CQI compression module and configured to transmit the compressed CQI to a serving base station. In one embodiment, the feedback decoder includes a receive module configured to receive a compressed CQI in the base station from user equipment corresponding to at least one sub-band. The feedback decoder also includes a CQI restoration module coupled to the receive module and configured to provide a restored CQI from the compressed CQI for the at least one sub-band.Type: GrantFiled: February 22, 2008Date of Patent: June 14, 2011Assignee: Texas Instruments IncorporatedInventors: Badri Varadarajan, Eko No. Onggosanusi, Runhua Chen, Il H. Kim
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Publication number: 20100272192Abstract: A device for communicating digital data over power lines includes a power line interface for transmitting data over at least one band of frequencies. An orthogonal frequency division multiplexing (OFDM) modulation unit generates OFDM symbols using a set of tones for the frequency band. A preamble generation unit generates preamble sequences for the frequency band by using the set of tones used by the OFDM modulation unit. The tones used by the preamble generation unit have a constant magnitude, and a set of phases obtained by quantizing to a small alphabet the phase of a set of tones obtained by taking an IFFT of a portion of a preamble used by a non-interoperable powerline access device. The device may transmit on two or more bands using a sampling frequency clock, wherein a lower band clock frequency is equal to or an integer divisor of a higher band clock frequency.Type: ApplicationFiled: April 27, 2010Publication date: October 28, 2010Inventors: Badri Varadarajan, Anand Dabak, Shu Du, Il Han Kim
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Publication number: 20100061360Abstract: A transmitter is for use with a cellular communication network and includes a beamforming generation unit configured to generate a downlink beamforming transmission corresponding to multiple-layer spatial multiplexing and based on a dedicated reference signal pattern. Additionally, the transmitter also includes a transmit unit configured to transmit the downlink beamforming transmission. A receiver is for use with a cellular communication network and includes a receive unit configured to receive a downlink beamforming transmission, and a beamforming processing unit configured to process the downlink beamforming transmission corresponding to multiple-layer spatial multiplexing and based on a dedicated reference signal pattern.Type: ApplicationFiled: September 10, 2009Publication date: March 11, 2010Applicant: Texas Instruments IncorporatedInventors: Runhua Chen, Anand G. Dabak, Eko N. Onggosanusi, Badri Varadarajan
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Publication number: 20100046412Abstract: A transmitter, for use with a cellular communication network, includes a reference signal generation unit configured to provide a reference signal corresponding to a reference signal structure for more than four transmit antennas. The transmitter also includes a system information signal generation unit configured to provide a system information signal corresponding to the reference signal structure for the more than four transmit antennas. The transmitter additionally includes a transmit unit configured to transmit the reference signal and the system information signal.Type: ApplicationFiled: August 24, 2009Publication date: February 25, 2010Applicant: Texas Instruments IncorporatedInventors: Badri Varadarajan, Eko N. Onggosanusi, Anand G. Dabak, Runhua Chen
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Publication number: 20090310782Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter includes a synchronization unit configured to provide a primary synchronization signal and a secondary synchronization signal having first and second segments. The transmitter also includes a secondary scrambling unit configured to provide a scrambled secondary synchronization signal, wherein scrambling agents for the first and second segments are derived from a primary synchronization sequence of the primary synchronization signal. The secondary scrambling unit is further configured to provide an additional scrambling of one of the first and second segments, wherein a second scrambling agent is derived from the remaining segment of a secondary synchronization sequence of the secondary synchronization signal.Type: ApplicationFiled: June 17, 2008Publication date: December 17, 2009Applicant: Texas Instruments IncorporatedInventors: Anand G. Dabak, Eko N. Onggosanusi, Badri Varadarajan
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Publication number: 20090268831Abstract: A transmitter includes a bandwidth configuration unit configured to provide an increased system bandwidth corresponding to a bandwidth extension over multiple component carriers. Additionally, the transmitter also includes a transmit unit configured to employ the bandwidth extension.Type: ApplicationFiled: April 21, 2009Publication date: October 29, 2009Applicant: Texas Instruments IncorporatedInventors: Eko N. Onggosanusi, Anand G. Dabak, Badri Varadarajan, Runhua Chen, Tarik Muharemovic
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Publication number: 20090257523Abstract: In one embodiment, a transmitter includes a binary sequence generator unit configured to provide a sequence of reference signal bits, wherein the sequence is an inseparable function of a cell identification parameter, a cyclic prefix mode corresponding to the transmitter and one or more time indices of the sequence. The transmitter also include a mapping unit that transforms the sequence of reference signal bits into a complex reference signal, and a transmit unit configured to transmit the complex reference signal. In another embodiment, a receiver includes a receive unit configured to receive a complex reference signal and a reference signal decoder unit configured to detect a sequence of reference signal bits from the complex reference signal, wherein the sequence is an inseparable function of a cell identification parameter, a cyclic prefix mode corresponding to a transmitter and one or more time indices of the sequence.Type: ApplicationFiled: December 2, 2008Publication date: October 15, 2009Applicant: Texas Instruments IncorporatedInventors: BADRI VARADARAJAN, ANAND G. DABAK, TARKESH PANDE, EKO N. ONGGOSANUSI
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Publication number: 20090017769Abstract: The present disclosure provides a receiver, a transmitter and methods of operating a receiver or a transmitter. In one embodiment, the receiver includes a receive unit configured to receive transmissions from multiple antennas. The receiver also includes a rank feedback unit configured to feed back a transmission rank selection, wherein the transmission rank selection corresponds to a transmission rank feedback reduction scheme. The receiver further includes a preceding feedback unit configured to feed back a preceding matrix selection, wherein the preceding matrix selection corresponds to a preceding matrix feedback reduction scheme.Type: ApplicationFiled: July 9, 2008Publication date: January 15, 2009Applicant: Texas Instruments IncorporatedInventors: Runhua Chen, Eko N. Onggosanusi, Badri Varadarajan, Anand G. Dabak