Patents by Inventor Karthikeyan Sundaresan

Karthikeyan Sundaresan 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).

  • Publication number: 20160269941
    Abstract: Methods and systems of asynchronous access and synchronous transmission include transmitting an initial reservation packet using a first protocol to prevent other devices that use the first protocol from transmitting during a reserved duration. A carrier using a second protocol is activated. Information is transmitted using a second protocol during the reserved duration. During a last subframe of the reserved duration, an additional reservation packet is transmitted using the first protocol to extend the reserved duration. The transmission of the additional reservation packet takes place while the carrier using the second protocol is still active.
    Type: Application
    Filed: March 1, 2016
    Publication date: September 15, 2016
    Inventors: Eugene Chai, Karthikeyan Sundaresan, Mohammad Khojastepour, Sampath Rangarajan, Krishna Garikipati
  • Publication number: 20160270031
    Abstract: A system and method for network-wide broadcasting, including identifying interference dependencies between base stations (eNBs) to generate one or more single frequency network (SFN) clusters for one or more broadcast sessions. The generating of SFN clusters includes performing a controlled decrease in transmit diversity gain for each of the sessions by progressively creating smaller SFN clusters, iteratively creating the smaller SFN clusters until a target modulation and coding scheme (MCS) threshold is met to generate a plurality of SFN clusters, and selecting an SFN cluster with a maximum common MCS for all SFN clusters in a set. Resource block (RB) allocation is integrated with the generating of the SFN clusters to determine maximum system utility, and the system utility considers the sum of the utilities of broadcast and unicast flows. Network-wide broadcasting is controlled based on the determined maximum system utility.
    Type: Application
    Filed: March 10, 2016
    Publication date: September 15, 2016
    Inventors: Karthikeyan Sundaresan, Mustafa Arslan, Rajarajan Sivaraj
  • Publication number: 20160269297
    Abstract: Methods and systems for load balancing on a control plane include calculating a hash of a unique identifier using a processor. The unique identifier is associated with a requesting device issuing a control request. The hash is mapped to a control plane processing device. The control request is forwarded to the control plane processing device.
    Type: Application
    Filed: March 9, 2016
    Publication date: September 15, 2016
    Inventors: Rajesh Mahindra, Karthikeyan Sundaresan, Arijit Banerjee, Sampath Rangarajan
  • Patent number: 9413474
    Abstract: Methods and systems for beam forming include measuring channel state information for a set of different codebook entries. An angle of arrival (AoA) distribution is determined with a processor using compressive testing based on the measured channel state information. A set of phase shift values is determined based on the determined AoA to perform phased array beamforming.
    Type: Grant
    Filed: June 12, 2015
    Date of Patent: August 9, 2016
    Assignee: NEC Corporation
    Inventors: Eugene Chai, Xiufeng Xie, Mohammad Khojastepour, Karthikeyan Sundaresan, Sampath Rangarajan
  • Patent number: 9337966
    Abstract: A method implemented in a mobile communications system is disclosed. The method includes selecting primary component carrier cp for a new user according to a formula, and performing joint secondary CC selection for one or more Long Term Evolution (LTE)-Advanced users and resource scheduling for one or more LTE users and said one or more LTE-Advanced users. Other methods, systems, and apparatuses also are disclosed.
    Type: Grant
    Filed: July 19, 2013
    Date of Patent: May 10, 2016
    Assignee: NEC Corporation
    Inventors: Karthikeyan Sundaresan, Sampath Rangarajan
  • Publication number: 20160094274
    Abstract: A method for managing a power line communication network in a multi-flow environment. The method includes determining an average throughput between each pair of nodes acting in isolation within the power line communication network, defining logical zones by grouping each pair of nodes if the average throughput between the pair of nodes exceeds a first threshold, wherein the logical zones include a plurality of strongly coupled zones. The method further includes determining an aggregate throughput for a pair of flows between randomly selected pairs of nodes acting concurrently between the plurality of strongly coupled zones, determining a plurality of pair of flows that can be concurrently operated when the aggregate throughput exceeds the average throughput, estimating a resulting throughput of the plurality of pair of flows that can be concurrently operated, and optimizing a schedule for the plurality of pair of flows based on the resulting throughput.
    Type: Application
    Filed: September 4, 2015
    Publication date: March 31, 2016
    Inventors: Karthikeyan Sundaresan, Mohammad Khojastepour, Sampath Rangarajan, Ahmed O. F. Atya
  • Publication number: 20160036504
    Abstract: A method, system, and computer program product for minimizing intra-cell and inter-cell interference in a multi-cell full duplex communication system in a wireless network. The method includes selecting, by a clint selector, a plurality of clients, wherein the plurality of clients includes a plurality of uplink clients configured to transmit signals and a plurality of downlink clients configured to receive signals over a plurality of data streams in each cell of the multi-cell full duplex communication system, and performing, by a spatial interference aligner, spatial interference alignment on interfering data streams to align the interfering data streams of uplink clients towards downlink clients in its own cell and downlink clients in a neighboring cell.
    Type: Application
    Filed: July 28, 2015
    Publication date: February 4, 2016
    Inventors: Mohammad Khojastepour, Karthikeyan Sundaresan, Sampath Rangarajan
  • Publication number: 20150381335
    Abstract: A method implemented in an access point (AP) used in a wireless communications system including a first uplink (UL) client device, a second UL client device, and a first downlink (DL) client device is disclosed. The method comprises: receiving, from the first DL client device, first composite channel matrix M1 comprising a first channel matrix and a second channel matrix, wherein the first DL client device estimates the first channel matrix and the second channel matrix. Other methods, systems, and apparatuses also are disclosed.
    Type: Application
    Filed: August 5, 2015
    Publication date: December 31, 2015
    Inventors: Mohammad Khojastepour, Karthikeyan Sundaresan, Eugene Chai, Sampath Rangarajan
  • Publication number: 20150381248
    Abstract: A method implemented in an access point (AP) having N antennas used in a wireless communications system including two first client devices each of which has M antennas and two second client devices each of which has N antennas, where M and N are even is disclosed. The method comprises: performing interference alignment (IA) in common vector spaces; and delivering M+N streams. Other methods, systems, and apparatuses also are disclosed.
    Type: Application
    Filed: August 5, 2015
    Publication date: December 31, 2015
    Inventors: Mohammad Khojastepour, Karthikeyan Sundaresan, Eugene Chai, Sampath Rangarajan
  • Publication number: 20150381334
    Abstract: A method implemented in a wireless communications system including a first uplink (UL) client device, a second UL client device, a first downlink (DL) client device, and an access point (AP) is disclosed. The method comprises the following steps in this order: a) determining interference alignment (IA) solution between the first and second UL client devices and the first device; and b) determining, according to the IA solution, receive filter U0 for the AP and precoder V0 for the AP to improve a UL stream rate and a DL stream rate. Other methods, systems, and apparatuses also are disclosed.
    Type: Application
    Filed: August 5, 2015
    Publication date: December 31, 2015
    Inventors: Mohammad Khojastepour, Karthikeyan Sundaresan, Eugene Chai, Sampath Rangarajan
  • Publication number: 20150372743
    Abstract: Systems and methods for full-duplex communication in a communications network, including generating a combined channel matrix including two or more channel matrices and determining a null space and a basis for the combined channel matrix. Common, individual, and disjoint vector spaces are determined, and common vector space is determined for each of one or more receiving nodes and each or one or more transmitting nodes, disjoint vector spaces for each of the one or more nodes are determined based on the common vector space for each of the one or more nodes, and individual vector spaces are determined based on the common and the disjoint vector spaces. Signals are mapped at each of the nodes to determine corresponding vector spaces; and interference alignment is performed in common vector spaces and zero forcing in disjoint vector spaces using a hardware processor.
    Type: Application
    Filed: June 17, 2015
    Publication date: December 24, 2015
    Inventors: Mohammad Khojastepour, Karthikeyan Sundaresan
  • Publication number: 20150365142
    Abstract: Methods and systems for beam forming include measuring channel state information for a set of different codebook entries. An angle of arrival (AoA) distribution is determined with a processor using compressive testing based on the measured channel state information. A set of phase shift values is determined based on the determined AoA to perform phased array beamforming.
    Type: Application
    Filed: June 12, 2015
    Publication date: December 17, 2015
    Inventors: Eugene Chai, Xiufeng Xie, Mohammad Khojastepour, Karthikeyan Sundaresan, Sampath Rangarajan
  • Publication number: 20150365143
    Abstract: Methods and systems for beam forming, implemented in a base station used in a communication system, include measuring channel state information (CSI) for a number of active phased-array antennas less than a full number of phased-array antennas. Analog beam forming weights are determined using the measured CSI. An optimal digital precoder is determined from the analog beam forming weights. The analog beam forming weights and optimal digital precoder are applied to one phased-array antenna.
    Type: Application
    Filed: June 12, 2015
    Publication date: December 17, 2015
    Inventors: Eugene Chai, Xiufeng Xie, Mohammad Khojastepour, Karthikeyan Sundaresan, Sampath Rangarajan
  • Publication number: 20150312903
    Abstract: In a wireless communications system including a first transmission point and a second transmission point, a wireless communications method implemented in the first transmission point supporting coordinated multi-point transmission and reception (CoMP) is disclosed. The wireless communications method comprises transmitting to the second transmission point one or more CoMP hypothesis sets, and transmitting to the second transmission point a benefit metric corresponding to each CoMP hypothesis set, wherein the benefit metric can be a negative value. Other methods, systems, and apparatuses also are disclosed.
    Type: Application
    Filed: March 18, 2015
    Publication date: October 29, 2015
    Inventors: Narayan Prasad, Mohammad Khojastepour, Mustafa Arslan, Karthikeyan Sundaresan, Sampath Rangarajan
  • Publication number: 20150312893
    Abstract: A wireless communications method implemented in a transmission point (TP) used in a wireless communications system is disclosed. The wireless communications method comprises receiving, from another TP, channel state information (CSI) for a user equipment (UE), and receiving, from said another TP, user identification for the user equipment, wherein the signaling of the CSI for the user equipment enables user identification for the user equipment. Other methods, systems, and apparatuses also are disclosed.
    Type: Application
    Filed: March 18, 2015
    Publication date: October 29, 2015
    Inventors: Narayan Prasad, Mohammad Khojastepour, Mustafa Arslan, Karthikeyan Sundaresan, Sampath Rangarajan
  • Publication number: 20150281978
    Abstract: Disclosed are systems, methods and structures that provide improved spatial reuse of spectral resources in small-cell wireless networks including WiMAX, LTE, LTE-Advanced, etc. Advantageously, the systems and method disclosed while leveraging beamforming for spatial reuse across small cells also decouple it from per-frame scheduling at a small cell base station thereby allowing for beam selections to be computed with a granularity measured in seconds. In realizing these advantages, systems, methods and structures disclosed integrate beam selection with client association.
    Type: Application
    Filed: March 31, 2014
    Publication date: October 1, 2015
    Inventors: Jongwon YOON, Karthikeyan SUNDARESAN, Mohammad Ali KHOJASTEPOUR, Suman BANERJEE, Sampath RANGARAJAN
  • Patent number: 9137788
    Abstract: An apparatus used in a full duplex multiple-input multiple-output (MIMO) wireless communications system is disclosed. In an aspect, the apparatus includes a plurality of antennas, each of which is connected to a combination of at least a TX (transmit) RF (radio frequency) chain and an RX (receive) RF chain. The plurality of antennas are split into one or more transmit antennas and one or more receive antennas, and the apparatus communicates with another apparatus. Other apparatuses and some methods for wireless communications also are disclosed.
    Type: Grant
    Filed: August 17, 2012
    Date of Patent: September 15, 2015
    Assignee: NEC Laboratories America, Inc.
    Inventors: Mohammad A. Khojastepour, Sanaz Barghi, Karthikeyan Sundaresan, Sampath Rangarajan
  • Patent number: 9125047
    Abstract: A wireless communications system is disclosed. The system comprises a baseband processing unit (BBU) pool including one or more baseband processing units (BBUs), and a plurality of remote radio heads (RRHs) connected to the BBU pool through a front-haul network, wherein the wireless communications system has a plurality of sectors, each of which includes one or more small cells, each of which is deployed by one of the plurality of RRHs, wherein a BBUs is mapped to two or more RRHs in a sector in a one-to-many configuration, and a BBU is mapped to a single RRH in a sector in a one-to-one configuration, and wherein a combination of the one-to-one configuration and the one-to-many configuration is applied to each sector. Other systems, apparatuses, and methods also are disclosed.
    Type: Grant
    Filed: July 25, 2013
    Date of Patent: September 1, 2015
    Assignee: NEC Laboratories America, Inc.
    Inventors: Karthikeyan Sundaresan, Cheng Liu, Mustafa Arslan, Meilong Jiang, Sampath Rangarajan
  • Publication number: 20150223173
    Abstract: An interference alignment system for communication structures that includes a single cell channel comprising an access point node, and a full bipartite interference channel (FBIC) configuration of a plurality of receiving nodes and a plurality of transmitting nodes. Each receiving node sees an interfering signal from all transmitting nodes. The access point node of the single cell channel provides a single node having downlink channels to all receiving nodes in the FBIC, and all of the uplink channels from the FBIC are to the single access point node to the single cell channel.
    Type: Application
    Filed: December 4, 2014
    Publication date: August 6, 2015
    Inventors: Mohammad Khojastepour, KARTHIKEYAN SUNDARESAN, Eugene Chai, Sampath Rangarajan
  • Patent number: 9066351
    Abstract: Systems and methods for data transmission include categorizing users into one of a plurality of profiles using a processor based on device and channel characteristics. Each of the plurality of profiles is mapped to one of a plurality of transmission schemes. Data is combined for a plurality of users categorized with different profiles for data transmission.
    Type: Grant
    Filed: July 19, 2013
    Date of Patent: June 23, 2015
    Assignee: NEC Laboratories America, Inc.
    Inventors: Karthikeyan Sundaresan, Mohammad A. Khojastepour, Sampath Rangarajan