Patents by Inventor Mohammad A. Khojastepour

Mohammad A. Khojastepour 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).

  • Patent number: 10582529
    Abstract: A system is provided for speculative scheduling that includes a base station having a processor. The processor computes an overall schedule for a set of clients. The overall schedule is formed from a set of speculative schedules, is configured to maximize unlicensed spectrum usage, and is computed by (a) determining a speculative schedule for each resource block from a set of resource blocks in a given sub-frame based on statistics determined for the clients individually and jointly, and (b) selecting, for formation into the overall schedule, (i) a particular resource block and (ii) the speculative schedule for the particular resource block, that yield the maximum incremental utility relative to already determined speculative schedules for other resource blocks in the set, based on criteria including uplink access statistics. The processor executes the overall schedule responsive to a completion of the speculative schedule determination for each resource block in the given sub-frame.
    Type: Grant
    Filed: March 8, 2018
    Date of Patent: March 3, 2020
    Assignee: NEC Corporation
    Inventors: Karthikeyan Sundaresan, Eugene Chai, Mohammad Khojastepour, Sampath Rangarajan
  • Patent number: 10574535
    Abstract: A method implemented in wireless communication systems for finding a topology of a network of communication nodes is presented. The method includes defining a set of the communication nodes as measurement nodes that identify if a channel is available or occupied at a particular time, determining, via a central controller that has access to measurements of at least one measurement node of the measurement nodes, a probability of availability or occupancy of the channel for the at least one measurement node and determining a joint probability of availability or occupancy of the channel for multiple measurement nodes for which a measurement is available, and computing, via a central decision device, the network topology from the determined probabilities.
    Type: Grant
    Filed: July 24, 2018
    Date of Patent: February 25, 2020
    Assignee: NEC Corporation
    Inventors: Mohammad Khojastepour, Karthikeyan Sundaresan, Eugene Chai, Sampath Rangarajan
  • Publication number: 20200050807
    Abstract: Systems and methods for sequential detection-based classifications of radio-frequency identification (RFID) tags in three-dimensional space are provided. The methods include modeling a response from RFID tags as a probabilistic macro-channel and interrogating an RFID tag by transmitting a series of packets. Each packet is a transmit symbol and a first series of packet is a transmitted codeword. The method includes receiving, from the RFID tag, a second series of packets that is a received codeword in response to the transmitted codeword and finding a jointly typical transmit and receive codeword across all classes of macro-channels. The method also includes declaring a class of the RFID tag based on a largest likelihood between the transmitted codeword and the received codeword.
    Type: Application
    Filed: July 22, 2019
    Publication date: February 13, 2020
    Inventors: Mohammad Khojastepour, Mustafa Arslan, Sampath Rangarajan
  • Publication number: 20200037304
    Abstract: Systems and methods for robust beam tracking and data communication data are provided. The method includes dividing, by a base station, time into frames each having two phases, a location probing phase and a data communication phase. In the location probing phase, the base station uses a fractional search policy to localize a mobile device by transmitting multiple probing packets over different time-slots and updates information about a location of the mobile device. In the data communication phase, the base station communicates with the mobile device while expanding a beamwidth to compensate for possible mobility of the mobile device.
    Type: Application
    Filed: July 18, 2019
    Publication date: January 30, 2020
    Inventors: Mohammad Khojastepour, Shahram Shahsavari
  • Patent number: 10469188
    Abstract: A computer-implemented method executed on a processor for employing an epoch-based approach to estimating interference in an unlicensed spectrum is presented. The method includes enabling communication between a long-term evolution (LTE) evolved node B (eNodeB) and a plurality of clients, detecting and measuring the interference in all existing non-overlapping channels, via the LTE eNodeB, caused by one or more hidden clients of the plurality of clients, collecting interference statistics from all of the plurality of clients across all different channels, and leveraging interference-awareness resulting in channel access performance improvement at a macro-time scale and a micro-time scale.
    Type: Grant
    Filed: July 19, 2018
    Date of Patent: November 5, 2019
    Assignee: NEC Corporation
    Inventors: Karthikeyan Sundaresan, Eugene Chai, Ramanujan Sheshadri, Mohammad Khojastepour, Sampath Rangarajan
  • Patent number: 10455636
    Abstract: A computer-implemented method for establishing communication links in a millimeter wave (mmWave) network by solving a linear integer packing problem is presented. The computer-implemented method includes determining active communication links between a plurality of transmitters and a plurality of receivers, setting each active communication link to have any arbitrary chosen weight or priority, and setting a minimum link quality threshold for each active communication link and subjecting each active communication link to constraints. Detected phantom constraints are mitigated by introducing new constraints with binary coefficients and by modifying one or more existing constraints by setting a number of coefficients within the existing constraints to zero.
    Type: Grant
    Filed: August 16, 2017
    Date of Patent: October 22, 2019
    Assignee: NEC Corporation
    Inventors: Narayan Prasad, Mohammad Khojastepour, Sampath Rangarajan, Yasaman Ghasempour
  • Publication number: 20190311162
    Abstract: A Radio Frequency Identification (RFID) localization system is provided. The system includes a set of passive RFID tags, each for reflecting transmitted signals. The system further includes an RFID reader for detecting the reflected signals by the passive RFID tags. The system also includes a processor for localizing an object in an area based on the reflected signals by computing signatures using probabilistic macro-channels between the RFID reader and locations of the passive RFID tags. The transmitted signals form inputs to the probabilistic macro-channels, and the signatures form outputs from the probabilistic macro-channels.
    Type: Application
    Filed: April 5, 2019
    Publication date: October 10, 2019
    Inventors: Mohammad Khojastepour, Mustafa Arslan, Sampath Rangarajan
  • Publication number: 20190278302
    Abstract: A computer-implemented method, system, and computer program product are provided for positioning an unmanned autonomous vehicle (UAV) in a long term evolution radio access network. The method includes acquiring, by a processor-device, a position of the UAV with a global position system. The method also includes determining, by the processor-device, physical distances from the UAV to each of a plurality of user equipment (UE) responsive to a time-of-flight from the UAV to each of the plurality of UE. The method additionally includes generating, by the processor-device, radio environment maps for each of the plurality of UE with signal-to-noise ratios (SNR) from each of the plurality of UEs to the UAV. The method further includes selecting, by the processor-device, a determined position for the UAV as a position with a minimum SNR in the REMs. The method also includes commanding the UAV to move to the determined position.
    Type: Application
    Filed: March 1, 2019
    Publication date: September 12, 2019
    Inventors: Karthikeyan Sundaresan, Eugene Chai, Sampath Rangarajan, Mohammad Khojastepour, Ayon Chakraborty
  • Patent number: 10405373
    Abstract: A system for implementing a distributed core architecture of a wireless communication network is provided. The system includes a plurality of devices configured to communicate with one or more UE devices to implement the wireless communication network. A given one of the plurality of devices includes at least one processor operatively coupled to a memory and a core agent implemented by the at least one processor. The core agent includes a controller for controlling functionality of the device, a switch operatively coupled to the controller, a precomputed policy data store for storing precomputed policies associated with at least security and service, mobility and policy applications, and a set of core applications including an inter-agent communication application for communicating with other core agents associated with other devices of the wireless communication network, and a control application for controlling the device.
    Type: Grant
    Filed: July 17, 2018
    Date of Patent: September 3, 2019
    Assignee: NEC CORPORATION
    Inventors: Eugene Chai, Mohammad Khojastepour, Karthikeyan Sundaresan, Sampath Rangarajan, Mehrdad Moradi
  • Patent number: 10405209
    Abstract: A system, method, and computer program product are provided for blue-printing interference for mobile access in an unlicensed spectrum of a synchronous scheduled cellular access system. The system includes a cellular base station having a processor. The processor constructs and executes an intelligent measurement schedule of clients for uplink transmissions to obtain access measurements for the uplink transmissions. The intelligent measurement schedule is constructed for scalable access measurement overhead. The access measurements indicate interference dependencies between the clients. The processor estimates an interference topology and statistics of the interference topology, from the access measurements to form an interference blueprint. The processor adjusts the intelligent measurement schedule to overschedule the clients for the uplink transmissions to reduce spectrum utilization loss while minimizing client transmission collisions, based on the interference blueprint.
    Type: Grant
    Filed: March 8, 2018
    Date of Patent: September 3, 2019
    Assignee: NEC CORPORATION
    Inventors: Karthikeyan Sundaresan, Eugene Chai, Mohammad Khojastepour, Sampath Rangarajan
  • Patent number: 10346655
    Abstract: Aspects of the present disclosure describe a battery-free touch sensing user interface (UI) for Internet of Things (IoT) and other smart spaces employing Radio Frequency Identification (RFID) readers and tags that we call RIO. With RIO, any surface may be a touch-aware surface by attaching RFID tag(s) thereto. RIO advantageously supports custom-designed RFID tags and therefore facilitates customized UIs to be easily deployed in a real-world environment. RIO employs impedance tracking that results from a human finger—or other appendage—touching a surface of an RFID tag, thereby changing a characteristic impedance of the RFID tag antenna. This change manifests as a change in the phase of the RFID backscattered signal and is advantageously used by RIO to track fine-grained touch movement over the RFID tag. Disclosed further are multi-tag environments in which RIO operates and demonstrations including continuous tracking of finger movement during a swipe to within 3 mm of its actual position.
    Type: Grant
    Filed: December 6, 2017
    Date of Patent: July 9, 2019
    Assignee: NEC Corporation
    Inventors: Eugene Chai, Swadhin Pradhan, Sampath Rangarajan, Mohammad Khojastepour, Karthikeyan Sundaresan
  • Patent number: 10332398
    Abstract: Systems and methods for detecting occupancy of at least one parking space by a vehicle are described. Detecting occupancy of at least one parking space includes at least one tag device fixed to a respective one of the at least one parking space. A first reader device is configured to interrogated the at least one tag device and detect a reply signal from the at least one tag device. A processor is configured to analyze the reply signal from the tag device including analyzing a received signal strength indication and a differential phase change of the reply signal to determine the presence of a vehicle in the parking space due to interference of the received signal by a signal blocking body.
    Type: Grant
    Filed: January 18, 2018
    Date of Patent: June 25, 2019
    Assignee: NEC Corporation
    Inventors: Mohammad Khojastepour, Mustafa Arslan, Sampath Rangarajan
  • Patent number: 10331493
    Abstract: A system and method are provided. The method includes a base station receiving a plurality of tasks from a plurality of user devices, each of the plurality of tasks involving a respective one of multiple sets of jobs. The method further includes a load balancer generating task allocations for the plurality of tasks, responsive to receiving the plurality of tasks from the base station. A unique task ID is generated for and assigned to each task, from which a task allocation is generated by the load balancer. The task allocations for the plurality of tasks are generated such that all the jobs received from a respective same one of the plurality of user devices are assigned to a same one of the worker entities in the set. The method also includes a set of worker entities performing the plurality of tasks in accordance with the task allocations.
    Type: Grant
    Filed: November 1, 2016
    Date of Patent: June 25, 2019
    Assignee: NEC Corporation
    Inventors: Mohammad Khojastepour, Rajesh Mahindra, Karthikeyan Sundaresan, Sampath Rangarajan
  • Publication number: 20190190573
    Abstract: A method implemented in a base station used in a wireless communications system is disclosed. The method comprises having 1-layer, 2-layer, 3-layer, and 4-layer codebooks for 4 transmit antenna (4TX) transmission, each codebook including a plurality of precoding matrices, precoding data with one of the plurality of precoding matrices, and transmitting, to a user equipment, the precoded data, wherein each of the 1-layer and 2-layer codebooks comprises a first codebook and a second codebook, and wherein each precoding matrix in the first codebook comprises a first index and a second index. Other apparatuses, systems, and methods also are disclosed.
    Type: Application
    Filed: February 21, 2019
    Publication date: June 20, 2019
    Inventors: Narayan PRASAD, Guosen YUE, Mohammad KHOJASTEPOUR, Sampath RANGARAJAN
  • Patent number: 10296394
    Abstract: Computer-implemented methods and a system are provided for distributing tasks between a plurality of processes in a computer network. A method includes distributing, by a load balancer in the computer network, tasks between the plurality of processes. The method further includes maintaining, by the load balancer, a registry for each of the tasks. For a given task, the registry indicates which of the plurality of processes to which the given task is distributed based on a hash function. The method also includes forming, by the load balancer, a respective set of registries for each of the plurality of processes, based on a set of thresholds. The method additionally includes redefining, by the load balancer, the set of thresholds when one of the plurality of processes ceases or a new process, added to the plurality of processes, commences.
    Type: Grant
    Filed: November 28, 2016
    Date of Patent: May 21, 2019
    Assignee: NEC Corporation
    Inventors: Mohammad Khojastepour, Rajesh Mahindra, Sampath Rangarajan, Karthikeyan Sundaresan
  • Patent number: 10298671
    Abstract: A load balancing device and method are provided. The load balancing device includes a processor. The processor is configured to receive a plurality of tasks from a plurality of user devices, each of the plurality of tasks involving a respective one of multiple sets of sessions. The processor is further configured to generate a task ID for each of the plurality tasks using a randomization function, at least one task ID for at least one of the plurality of tasks changing over time responsive to one or more criterion. The processor is additionally configured to allocate the plurality of tasks amongst a set of worker entities such that all the sessions involved in the plurality of tasks received from a respective same one of the plurality of user devices is assigned to a same one of the worker entities in the set.
    Type: Grant
    Filed: November 1, 2016
    Date of Patent: May 21, 2019
    Assignee: NEC Corporation
    Inventors: Mohammad Khojastepour, Rajesh Mahindra, Karthikeyan Sundaresan, Sampath Rangarajan
  • Patent number: 10292059
    Abstract: A computer-implemented method executed in a wireless communication system for establishing communication links in a millimeter wave network is presented. The method includes determining active communication links between a plurality of transmitters and a plurality of receivers operated by a plurality of users and formulating a quality of service (QoS) proportional fairness (PF) network utility as a constrained submodular set function maximization problem. The method further includes performing an optimization framework by optimizing, based on the active communication links, user association for fixed transmit beam patterns and optimizing, based on the active communication links, the fixed transmit beam patterns and corresponding beam attributes for a fixed set of user associations.
    Type: Grant
    Filed: January 18, 2018
    Date of Patent: May 14, 2019
    Assignee: NEC Corporation
    Inventors: Mohammad Khojastepour, Narayan Prasad, Sampath Rangarajan, Yasaman Ghasempour
  • Patent number: 10292054
    Abstract: Methods and a system are provided for enabling coexistence of WIFI and Long Term Evolution (LTE) in a wireless communication system. A method includes embedding in a data sequence, by a base station capable of transmitting and receiving LTE frames, a channel reservation packet that (i) is detectable by a WIFI receiver and (ii) reserves a particular one of a plurality of available unlicensed communication channels for a transmission duration of the data sequence. The method further includes transmitting, by the base station, the data sequence including the embedded channel reservation packet.
    Type: Grant
    Filed: February 1, 2017
    Date of Patent: May 14, 2019
    Assignee: NEC Corporation
    Inventors: Mohammad Khojastepour, Eugene Chai, Karthikeyan Sundaresan, Sampath Rangarajan
  • Patent number: 10291370
    Abstract: Methods and systems for assigning users to nodes include assigning user devices to respective macro nodes in a wireless network. Each of the user devices is assigned to a respective pico node in the wireless network. Each respective pico node is associated with the same macro node that the respective user device is assigned to. Resource allocation fractions are assigned to all pico nodes and all macro nodes in the wireless network based on the assignment of each of the plurality of user devices respective macro nodes and pico nodes.
    Type: Grant
    Filed: January 10, 2018
    Date of Patent: May 14, 2019
    Assignee: NEC Corporation
    Inventors: Narayan Prasad, Mohammad Khojastepour, Sampath Rangarajan
  • Patent number: 10250310
    Abstract: A method implemented in a base station used in a wireless communications system is disclosed. The method comprises having 1-layer, 2-layer, 3-layer, and 4-layer codebooks for 4 transmit antenna (4TX) transmission, each codebook including a plurality of precoding matrices, precoding data with one of the plurality of precoding matrices, and transmitting, to a user equipment, the precoded data, wherein each of the 1-layer and 2-layer codebooks comprises a first codebook and a second codebook, and wherein each precoding matrix in the first codebook comprises a first index and a second index. Other apparatuses, systems, and methods also are disclosed.
    Type: Grant
    Filed: July 26, 2017
    Date of Patent: April 2, 2019
    Assignee: NEC Corporation
    Inventors: Narayan Prasad, Guosen Yue, Mohammad Khojastepour, Sampath Rangarajan