Patents Assigned to Centre of Excellence in Wireless Technology
  • Patent number: 9661643
    Abstract: Cognitive interference management in Cellular wireless network with relays and micro/pico/femto cells operated in distributed scheduling mode. A cellular system may use RS to improve capacity or for coverage extension. ARS relays the signals between BS 104 and MS by using wireless links between BS-RS and RS-MS during both downlink and uplink transmissions. Embodiments herein disclose a mechanism to explicitly indicate to the MS whether the MAC management messages sent by the BS to the MS are to inform it to perform scanning for interference measurement. Also, disclosed herein is a mechanism to explicitly indicate to the BS whether the message sent by the MS is related to interference measurement.
    Type: Grant
    Filed: March 18, 2015
    Date of Patent: May 23, 2017
    Assignee: CENTRE OF EXCELLENCE IN WIRELESS TECHNOLOGY
    Inventors: Sheetal Kalyani, Sunil Kaimalettu, Rajet Krishnan, Nadeem Akhtar, Jeniston Deviraj Klutto Milleth, Kiran Kumar Kuchi, Bhaskar Ramamurthi
  • Patent number: 9641237
    Abstract: The embodiments herein disclose an indoor personal relay which has a wireless interface with the BS, which is effective in both cost and technology terms. The indoor personal relay, as disclosed herein is an estimate and forward relay. The relay 101 as disclosed herein does not perform any additional channel decoding/encoding on the data that it receives from the UE or BS. Embodiments disclosed herein enable the relevant UEs to have a high SINR link with the relay. This, in turn, translates to a better effective link quality between the UE and BS and higher indoor rates, which otherwise may have been not as good as a consequence of poor direct link between the UE and the BS. This relay is effectively transparent to the UE. The deployment of relays also implies minimal impact on UE IOT.
    Type: Grant
    Filed: April 30, 2015
    Date of Patent: May 2, 2017
    Assignee: Centre of Excellence in Wireless Technology
    Inventors: Nadeem Akhtar, Rajet Krishnan, Sheetal Kalyani, Sunil Kaimalettu, Bhaskar Ramamurthi
  • Patent number: 9564987
    Abstract: The embodiments described herein provide a method and system for improve link adoption performance in wireless networks. The method for modifying the MCS index for transmission using a computed offset is provided. The offset is calculated based on HARQ feedback of transmissions. A transition probability matrix with plurality of MCS indices is used for selecting the MCS index for transmission based on the highest probability of transition. A pattern sequence of MCS indices is formed and the presence of the pattern is determined in the history of the HARQ transmissions. The frequency of the pattern presence is also determined and the MCS index is selected for the HARQ transmissions. A frequency database of MCS indices is built using source encoding techniques. The transition probabilities that are estimated from the frequency database along with a cost function associated with each MCS index will be used to compute next MCS index.
    Type: Grant
    Filed: February 9, 2015
    Date of Patent: February 7, 2017
    Assignee: CENTRE OF EXCELLENCE IN WIRELESS TECHNOLOGY
    Inventors: Sheetal Kalyani, Narendran Krishnan, Saishankar Katri Pulliyakode
  • Publication number: 20160173208
    Abstract: A communication network comprising of at least one remote base station; and a plurality of antenna ports connected to the at least one remote base station; wherein the remote base station controls the plurality of antenna ports. The remote base station is configured for defining mutually exclusive entry and exit points for the antenna ports in at least one of time; or frequency. Also, disclosed herein is a communication network comprising of at least one network controller and at least one base station, wherein the network controller is configured for assigning entry and exit points for each base station.
    Type: Application
    Filed: May 9, 2012
    Publication date: June 16, 2016
    Applicants: Centre of Excellence in Wireless Technology, Indian Institute ofTechnology Madras, Indian Institute of Technology Hyderabad
    Inventors: Kiran Kumar Kuchi, Bhaskar Ramamurthi, Jeniston Deviraj Klutto Milleth, Sivakishore Reddy Yerrapareddy, Sunil Kaimalettu, Naga Sekhar Suruvu, Dhivagar Baskaran, Giridhar Krishnamurthi, Padmanabhan Madampu Suryasarman
  • Patent number: 9312978
    Abstract: Embodiments disclosed herein reduce interference at pilot symbols and also enable good interference measurements by using a combination pilot tones and null tones along with null tones. In this type of system, the receivers estimate the channel state information without any strong interference from the neighboring transmitters, and at the same time it can also measure either the individual interference channel states or the interference covariances from the silent periods. It uses these measurements thus obtained to calculate the post processing SINR, and then compute and report the wideband and subband CQIs to the transmitter. The groups of transmitters are reused in geographically separated region using a frequency reuse structure. In a preferred implementation, pilot signal is precoded using a multi-antenna precoder. The precoder may be same for pilot and data.
    Type: Grant
    Filed: April 12, 2015
    Date of Patent: April 12, 2016
    Assignee: Centre of Excellence in Wireless Technology
    Inventors: Kiran Kumar Kuchi, Jeniston Deviraj Klutto Milleth, Vinod Ramaswamy, Baskaran Dhivagar, Dileep Manisseri Kalathil, Krishnamurthi Giridhar, Bhaskar Ramamurthi, Padmanabhan Madampu Suryasarman, Geordie George, Prasanth Karunakaran, Yerrapareddy Sivakishore Reddy
  • Patent number: 9231836
    Abstract: A system and method for estimating a channel in wireless communication systems using Orthogonal Frequency Division Multiplexing (OFDM). From the received OFDM symbols, Maximum Likelihood (ML) estimate of the channel frequency response is obtained at the pilot locations. A hypothesis test is performed on the ML estimates and the outcome of the hypothesis test is used to decide a shrinkage target. Biased estimation methods are used to shrink the ML estimates towards the shrinkage target to obtain better estimates of the channel frequency response at the pilot locations and these estimates are interpolated using a Filter to get a set of complete estimates of the channel over the resource block. The Filter is an Empirical Weiner Filter or a robust 2D-MMSE filter and the biased estimation is done using either a James-Stein (JS) estimator or a shrinkage estimator or an empirical Bayes estimator.
    Type: Grant
    Filed: June 11, 2010
    Date of Patent: January 5, 2016
    Assignee: Centre of Excellence in Wireless Technology
    Inventors: Sheetal Kalyani, Lakshminarayanan Raghavendran, Krishnamurthi Giridhar
  • Publication number: 20150236777
    Abstract: The embodiments herein disclose an indoor personal relay which has a wireless interface with the BS, which is effective in both cost and technology terms. The indoor personal relay, as disclosed herein is an estimate and forward relay. The relay 101 as disclosed herein does not perform any additional channel decoding/encoding on the data that it receives from the UE or BS. Embodiments disclosed herein enable the relevant UEs to have a high SINR link with the relay. This, in turn, translates to a better effective link quality between the UE and BS and higher indoor rates, which otherwise may have been not as good as a consequence of poor direct link between the UE and the BS. This relay is effectively transparent to the UE. The deployment of relays also implies minimal impact on UE IOT.
    Type: Application
    Filed: April 30, 2015
    Publication date: August 20, 2015
    Applicant: Centre of Excellence in Wireless Technology
    Inventors: Nadeem Akhtar, Rajet Krishnan, Sheetal Kalyani, Sunil Kaimalettu, Bhaskar Ramamurthi
  • Publication number: 20150215063
    Abstract: Embodiments disclosed herein reduce interference at pilot symbols and also enable good interference measurements by using a combination pilot tones and null tones along with null tones. In this type of system, the receivers estimate the channel state information without any strong interference from the neighboring transmitters, and at the same time it can also measure either the individual interference channel states or the interference covariances from the silent periods. It uses these measurements thus obtained to calculate the post processing SINR, and then compute and report the wideband and subband CQIs to the transmitter. The groups of transmitters are reused in geographically separated region using a frequency reuse structure. In a preferred implementation, pilot signal is precoded using a multi-antenna precoder. The precoder may be same for pilot and data.
    Type: Application
    Filed: April 12, 2015
    Publication date: July 30, 2015
    Applicant: Centre of Excellence in Wireless Technology
    Inventors: Kiran Kumar Kuchi, Jeniston Deviraj Klutto Milleth, Vinod Ramaswamy, Baskaran Dhivagar, Dileep Manisseri Kalathil, Krishnamurthi Giridhar, Bhaskar Ramamurthi, Padmanabhan Madampu Suryasarman, Geordie George, Prasanth Karunakaran, Yerrapareddy Sivakishore Reddy
  • Patent number: 9083399
    Abstract: Precoding for multiple transmission streams in multiple antenna systems. Disclosed herein is a general method that transmits signal from multiple antennas using a one/two dimensional precoder. This precoder is fixed in a given resource block (RB) or slot, which is composed of P subcarriers and Q OFDM symbols (where the values for P and Q are greater than or equal to 1). The precoder in each resource block may take same or different values, which span the two dimensional time-frequency grid. The precoder is chosen as a function of either logical frequency index or physical frequency index of the RB.
    Type: Grant
    Filed: June 18, 2009
    Date of Patent: July 14, 2015
    Assignee: Centre of Excellence in Wireless Technology
    Inventors: Kiran Kumar Kuchi, Deviraj Klutto Milleth Jeniston, Vinod Ramaswamy, Baskaran Dhivagar, Krishnamurthi Giridhar, Bhaskar Ramamurthi, Dileep Manisseri Kalathil, Padmanabhan Madampu Suryasarman
  • Publication number: 20150195843
    Abstract: Cognitive interference management in Cellular wireless network with relays and micro/pico/femto cells operated in distributed scheduling mode. A cellular system may use RS to improve capacity or for coverage extension. ARS relays the signals between BS 104 and MS by using wireless links between BS-RS and RS-MS during both downlink and uplink transmissions. Embodiments herein disclose a mechanism to explicitly indicate to the MS whether the MAC management messages sent by the BS to the MS are to inform it to perform scanning for interference measurement. Also, disclosed herein is a mechanism to explicitly indicate to the BS whether the message sent by the MS is related to interference measurement.
    Type: Application
    Filed: March 18, 2015
    Publication date: July 9, 2015
    Applicant: CENTRE OF EXCELLENCE IN WIRELESS TECHNOLOGY
    Inventors: Sheetal Kalyani, Sunil Kaimalettu, Rajet Krishnan, Nadeem Akhtar, Jeniston Deviraj Klutto Milleth, Kiran Kumar Kuchi, Bhaskar Ramamurthi
  • Patent number: 9049678
    Abstract: The embodiments herein disclose an indoor personal relay which has a wireless interface with the BS, which is effective in both cost and technology terms. The indoor personal relay, as disclosed herein is an estimate and forward relay. The relay 101 as disclosed herein does not perform any additional channel decoding/encoding on the data that it receives from the UE or BS. Embodiments disclosed herein enable the relevant UEs to have a high SINR link with the relay. This, in turn, translates to a better effective link quality between the UE and BS and higher indoor rates, which otherwise may have been not as good as a consequence of poor direct link between the UE and the BS. This relay is effectively transparent to the UE. The deployment of relays also implies minimal impact on UE IOT.
    Type: Grant
    Filed: May 25, 2011
    Date of Patent: June 2, 2015
    Assignee: Centre of Excellence in Wireless Technology
    Inventors: Nadeem Akhtar, Rajet Krishnan, Sheetal Kalyani, Sunil Kaimalettu, Bhaskar Ramamurthi
  • Patent number: 9036722
    Abstract: Present robust 2 Dimensional Minimum Mean Square Error (2D-MMSE) or minimax approach assumes significant time and frequency selectivity due to which it has a poor Mean Square Error (MSE) performance for Resource Blocks (RBs) with low/moderate frequency and/or time selectivity. A filter cannot be designed assuming low frequency and/or time selectivity and use that for all channel models. The instant invention proposes a Robust Adaptive (RA) MMSE filter that can bridge the gap between a robust 2D-MMSE/minimax and the optimal MMSE approach. The RA-MMSE filter smoothens the filter coefficients of the robust 2D-MMSE filter with the degree of smoothing adaptively changing with amount of frequency and time selectivity within a RB. The method uses multiple hypothesis tests on the maximum likelihood Channel Frequency Response (CFR) estimates at the pilots.
    Type: Grant
    Filed: October 7, 2011
    Date of Patent: May 19, 2015
    Assignee: Centre of Excellence in Wireless Technology
    Inventors: Sheetal Kalyani, Raghavendran Lakshminarayanan
  • Patent number: 9030992
    Abstract: Embodiments disclosed herein reduce interference at pilot symbols and also enable good interference measurements by using a combination pilot tones and null tones along with null tones. In this type of system, the receivers can estimate tile channel state information without any interference from the remaining transmitters and at the same time the receiver can measure either the individual interference channel states or the interference covariances from the silent periods. The groups of transmitters are reused in geographically separated region using a frequency reuse structure. In a preferred implementation, pilot signal is precoded using a multi-antenna precoder. The precoder may be same for pilot and data.
    Type: Grant
    Filed: March 3, 2010
    Date of Patent: May 12, 2015
    Assignee: Centre of Excellence in Wireless Technology
    Inventors: Kiran Kumar Kuchi, Jeniston Deviraj Klutto Milleth, Vinod Ramaswamy, Baskaran Dhivagar, Dileep Manisseri Kalathil, Krishnamurthi Giridhar, Bhaskar Ramamurthi, Padmanabhan Madampu Suryasarman, Geordie George, Prasanth Karunakaran, Yerrapareddy Sivakishore Reddy
  • Patent number: 9025537
    Abstract: An embodiment herein provides a method to mitigate effects of inter-cell interference in cellular communications, thereby maximizing SINR of a cellular device, due to a serving base station selecting a transmission strategy which places the signal strength (average and instantaneous) of the cellular device utilizing the base station in its in-phase region and inverse of interference signal strength (average and instantaneous) received by the cellular device from interfering base stations in their out-of phase region.
    Type: Grant
    Filed: February 6, 2009
    Date of Patent: May 5, 2015
    Assignee: Centre of Excellence in Wireless Technology
    Inventors: Bhaskar Ramamurthi, Joseph Vinosh Babu James
  • Patent number: 9014636
    Abstract: Cognitive interference management in Cellular wireless network with relays and micro/pico/femto cells operated in distributed scheduling mode. A cellular system may use RS to improve capacity or for coverage extension. A RS relays the signals between BS 104 and MS by using wireless links between BS-RS and RS-MS during both downlink and uplink transmissions. Embodiments herein disclose a mechanism to explicitly indicate to the MS whether the MAC management messages sent by the BS to the MS are to inform it to perform scanning for interference measurement. Also, disclosed herein is a mechanism to explicitly indicate to the BS whether the message sent by the MS is related to interference measurement.
    Type: Grant
    Filed: March 19, 2010
    Date of Patent: April 21, 2015
    Assignee: Centre of Excellence In Wireless Technology
    Inventors: Sheetal Kalyani, Sunil Kaimalettu, Rajet Krishnan, Nadeem Akhtar, Jeniston Deviraj Klutto Milleth, Kiran Kumar Kuchi, Bhaskar Ramamurthi
  • Patent number: 8902831
    Abstract: Embodiments herein provide methods and systems for enhancing interference mitigation using conjugate symbol repetition and phase randomization on a set of subcarriers. The repeated data tone in the signal is complex-conjugated before transmission, when the repetition factor is two. When the repetition factor is greater than two, a combination of conjugate repetition and random/deterministic phase variation of the repeated tones is used to mitigate the interference mitigation. Embodiments further disclose Collision Free Interlaced Pilot PRU Structures that can be used with or without conjugate symbol repetition and phase randomization for interference mitigation.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: December 2, 2014
    Assignee: Centre of Excellence in Wireless Technology
    Inventors: Kiran Kumar Kuchi, Deviraj Klutto Milleth Jeniston, Vinod Ramaswamy, Baskaran Dhivagar, Krishnamurthi Giridhar, Bhaskar Ramamurthi, Padmanabhan Madampu Suryasarman, Dileep Manisseri Kalathil
  • Patent number: 8873364
    Abstract: An Ordered Reduced Set Successive Detector (RSSD) for the V-BLAST spatial multiplexing scheme that uses a general two-dimensional non-uniform set partitioning for different symbols. The detector provides improved diversity and SNR gains at reduced complexity compared to a uniform set partitioning based detector. The detector can be used to reduce the complexity, with a small tradeoff in performance. Further, it is possible to obtain a quasi-ML performance using the disclosed detector at a reduced, yet fixed, complexity.
    Type: Grant
    Filed: January 18, 2013
    Date of Patent: October 28, 2014
    Assignees: Centre of Excellence in Wireless Technology, IIT-Hyderabad, IIT-Madras
    Inventors: Kiran Kumar Kuchi, Bhaskar Ramamurthi, Karthik Kuntikana Shrikrishna
  • Patent number: 8761308
    Abstract: Embodiments herein provide using extreme value theory (EVT) as a diagnostic to decide which taps are significant. In the low SINR scenario, embodiments herein also provide the following options; i) Fix the model order to a finite value smaller than the model order assumed for the initial CIR estimate. In the case of OFDM based systems, the model order of the CIR is fixed to a value much smaller that the cyclic prefix length. ii) Use the EVT based method to detect significant tap locations and only keep those tap locations such that the CIR length is again restricted to a value smaller than the model order of the initial channel estimate.
    Type: Grant
    Filed: December 29, 2009
    Date of Patent: June 24, 2014
    Assignee: Centre of Excellence In Wireless Technology
    Inventors: Sheetal Kalyani, Ganesh Venkatraman
  • Publication number: 20140133412
    Abstract: Embodiments disclosed herein relate to OFDM based data communication systems, and more particularly to mitigate Downlink-Downlink, Downlink-Uplink, Uplink-Downlink, Uplink-Uplink interference from same/adjacent channel in heterogeneous/homogeneous networks employing dynamic DL/UL configurations in OFDM based data communication systems.
    Type: Application
    Filed: November 7, 2013
    Publication date: May 15, 2014
    Applicant: Centre of Excellence in Wireless Technology
    Inventors: Klutto Milleth Jeniston Deviraj, Bhaskar Ramamurthi, Sunil Kaimalettu, Sivakishore Reddy Yerrapareddy, Babu Narayanan Koonampilli Janardhnan, Nadeem Akhtar, Lakshmana Babu Vulusala, Dhivagar Baskaran
  • Patent number: 8699446
    Abstract: Precoding for multiple transmission streams in multiple antenna systems. Embodiments herein disclose a general method that transmits signal from multiple antennas using a one/two dimensional precoder followed by STBC/SFBC or SM encoder. This precoder is fixed in a given resource block (RB) or slot, which is composed of P subcarriers and Q OFDM symbols (where the values for P and Q are greater than or 5 equal to 1). The precoder in each resource block may take same or different values, which span the two dimensional time-frequency grid. The precoder is chosen as a function of either logical frequency index or physical frequency index of the RB.
    Type: Grant
    Filed: June 18, 2009
    Date of Patent: April 15, 2014
    Assignee: Centre of Excellence In Wireless Technology
    Inventors: Kiran Kumar Kuchi, Deviraj Klutto Milleth Jeniston, Vinod Ramaswamy, Baskaran Dhivagar, Krishnamurthi Giridhar, Bhaskar Ramamurthi, Dileep Manisseri Kalathil, Padmanabhan Madampu Suryasarman