Patents by Inventor Krishna Sitaram

Krishna Sitaram 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: 9674861
    Abstract: Systems and methods are described for scheduling transmissions from an access node. A traffic distribution and usage pattern associated with an access node may be determined based on an inspection of packet transmission data. A scheduling algorithm may be assigned to a particular set of usage characteristics based on the determined traffic distribution and usage pattern. The traffic distribution and usage pattern associated with the access node may be monitored for a set of criteria. The scheduling algorithm may be selected based on the monitored traffic distribution and packet data for at least one wireless device may be transmitted using the selected scheduling algorithm.
    Type: Grant
    Filed: December 19, 2014
    Date of Patent: June 6, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Hemanth Pawar, Shilpa Kowdley, Krishna Sitaram, Daniel Vivanco
  • Patent number: 9668159
    Abstract: When a wireless device is configured to function as a relay for a donor access node, the donor access node is configured such that the relaying wireless device is given preferential treatment when compared to non-relaying wireless devices. The communication network and/or donor access node can be configured to provide improved RF conditions, higher throughput, lower latency, etc. to a relaying wireless device than is provided to non-relay wireless devices.
    Type: Grant
    Filed: May 12, 2015
    Date of Patent: May 30, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Hemanth Pawar, Chunmei Liu, Krishna Sitaram, Pratik Kothari
  • Patent number: 9668180
    Abstract: Systems and methods are described for identifying and resolving cell identifier confusion in a wireless network. A serving cell may determine that multiple neighboring cells have a duplicate cell identifier. The serving cells may receive signal measurement reports and network characteristics for the neighboring cells in order to determine if there is an opportunity for handover between the neighboring cells and the serving cell. If the multiple neighboring cells appear in a single signal measurement report from a single wireless device, there this is an opportunity for handover, and one of the neighboring cells may be instructed to change its cell identifier. However, the network characteristics indicate that the neighboring cell does not have coverage sector overlap, then there is no opportunity for handover and the neighboring cell may be removed from a database used by the serving cell during a handover process.
    Type: Grant
    Filed: September 4, 2014
    Date of Patent: May 30, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Daniel Vivanco, Chunmei Liu, Hemanth Pawar, Krishna Sitaram
  • Patent number: 9667402
    Abstract: Systems and methods are also described for mitigating interference at an access node. It may be determined, based on an interference metric for a first wireless device exceeding an interference criteria, that communication between the first wireless device and a cell of an access node is experiencing interference from a neighboring cell. A second wireless device receiving a beamformed transmission may be identified, wherein the beamformed transmission to the second wireless device is identified as an interference source for communication between the first wireless device and the cell of the access node. Transmissions to the first wireless device and the second wireless device may be scheduled such that the scheduled timings for transmissions to the first wireless device are different from the scheduling timings for transmissions to the second wireless device.
    Type: Grant
    Filed: September 17, 2015
    Date of Patent: May 30, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Chunmei Liu, Pratik Kothari, Krishna Sitaram, Hemanth Pawar
  • Patent number: 9660735
    Abstract: Systems and methods are also described for mitigating interference at an access node. It may determined, based on an interference metric for a first wireless device exceeding an interference criteria, that communication between the first wireless device and a cell of an access node is experiencing interference from a neighboring cell. At least one neighboring cell in which one or more beamformed signals are transmitted is identified as a potential interference source. The identified neighboring cell may be instructed to terminate transmission of a beamformed signal to at least a second wireless device. It may then be determined whether the interference metric for the first wireless device continues to exceed the interference criteria after the termination of the beamformed signal. And the second wireless device may be identified as an interference source when the interference metric for the first wireless device does not continue to exceed the interference criteria.
    Type: Grant
    Filed: September 17, 2015
    Date of Patent: May 23, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Chunmei Liu, Pratik Kothari, Krishna Sitaram, Hemanth Pawar
  • Patent number: 9655127
    Abstract: Disclosed is a method and system for dynamically managing carrier aggregation based on operating conditions of small cells in a wireless communication system. A first base station may be configured for providing wireless services on a first wireless carrier band and a second wireless carrier band. One or more additional base stations may each configured for providing wireless services on the second wireless carrier band. A determination can be made that a load on the one or more additional base stations exceeds a threshold level while each is providing wireless coverage within a region that at least partially overlaps with wireless coverage provided by the first base station. In response, the first base can be caused to refrain from aggregating the first and second wireless carrier bands for providing wireless services under operational conditions defined to cause the base station to aggregate the first and second wireless carrier bands.
    Type: Grant
    Filed: December 18, 2014
    Date of Patent: May 16, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Shilpa Kowdley Srinivas, Hemanth B. Pawar, Krishna Sitaram, Daniel A. Vivanco
  • Patent number: 9629136
    Abstract: Disclosed is method and apparatus to help reduce PRACH interference. In accordance with the disclosure, when a first base station determines that there is a threshold level of interference from a second base station, the first base station transmits to the second base station a directive that causes the second base station to reduce PUSCH transmission in PUSCH resources that are coincident in frequency with the first base station's PRACH. In a scenario where two base stations provide overlapping coverage and operate on the same frequency as each other, and where coverage of the second base station may interfere with coverage of the first base station, this process may thereby help to minimize or eliminate interference that PUSCH communication in the second base station's coverage area would have on PRACH communication in the first base station's coverage area.
    Type: Grant
    Filed: May 22, 2015
    Date of Patent: April 18, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Krishna Sitaram, Chunmei Liu, Hemanth B. Pawar, Pratik Kothari
  • Patent number: 9622242
    Abstract: At certain beamforming angles (i.e., those greater than a threshold amount) a sidelobe of a beamforming pattern used by a first sector may be pointed at wireless devices being serviced by a second sector. This causes the interference experienced by the first sector to be increased due to the transmissions of the wireless devices being serviced by the second sector. To help mitigate the interference experienced by the first sector, when the access node determines it is using a beamforming angle that may be susceptible to interference from the second sector (e.g., beamforming angle greater than a threshold), the first sector selects an amount of TTI bundling to be used by a wireless device. By configuring a wireless device to use TTI bundling (i.e., increase redundancy), the link budget for the wireless device is improved thereby lessening the effects of the interference being received via the sidelobe.
    Type: Grant
    Filed: December 7, 2015
    Date of Patent: April 11, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Hemanth Pawar, Shilpa Kowdley Srinivas, Krishna Sitaram, Chunmei Liu
  • Patent number: 9614651
    Abstract: When a first throughput between the wireless device and a first access node meets a threshold, an application requirement of an application running on the wireless device is determined. Measurements are received of a first signal level of the communication link between the wireless device and the first access node and a second signal level of a signal from a second access node received at the wireless device. A first data rate is estimated using a first communication scheme between the wireless device and the first and second access nodes, and a second data rate is estimated using a second communication scheme between the wireless device and the first and second access nodes. One of the communication schemes is selected for use by the wireless device and the first and second access nodes based on the estimated first data rate and the estimated second data rate and the application requirement.
    Type: Grant
    Filed: January 23, 2014
    Date of Patent: April 4, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Daniel Vivanco, Krishna Sitaram
  • Patent number: 9608794
    Abstract: Systems and methods are described for scheduling transmissions between an access node and wireless devices. A location may be determined for a plurality of small cells within an access node signal area. Based on the determined locations, a frame structure may be selected for the access node used to communicate with a plurality of wireless devices. Data may then be communicated between the access node and a plurality of wireless devices based on the selected frame structure.
    Type: Grant
    Filed: August 8, 2014
    Date of Patent: March 28, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Hemanth Pawar, Shilpa Kowdley, Krishna Sitaram, Daniel Vivanco
  • Patent number: 9591649
    Abstract: Disclosed is a method and system for reducing the load on a downlink control channel of a given carrier of a plurality of carriers in a coverage area. As disclosed, a base station may determine that the downlink control channel of the given carrier is threshold loaded. In response to this determination, the base station may then (a) identify a particular subset of the UEs that are currently designated for DCI transmission on the downlink control channel of the given carrier and then (b) take action to de-designate the identified subset of UEs for DCI transmission on the given carrier and instead designate the identified subset of UEs for DCI transmission only on one or more other carriers in the coverage area.
    Type: Grant
    Filed: September 29, 2014
    Date of Patent: March 7, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Chunmei Liu, Krishna Sitaram, Daniel A. Vivanco, Hermanth B. Pawar
  • Patent number: 9585072
    Abstract: Disclosed are methods and systems to facilitate handover of a UE away from a primary carrier of a base station, despite a primary carrier having a channel quality that is at or above a channel quality threshold of the primary carrier. In particular, a wireless communication system may serve the UE with carrier aggregation service using (i) a first carrier as a primary carrier for the UE and (ii) a second carrier as a secondary carrier for the UE. During the serving, while a channel quality of the primary carrier is at or above a first threshold quality, the system may make a determination that a channel quality of the secondary carrier is below a second threshold quality. In response to at least making the determination, the system may carry out a handover of the UE from the primary carrier of the first base station to another carrier.
    Type: Grant
    Filed: July 22, 2015
    Date of Patent: February 28, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Chunmei Liu, Hemanth B. Pawar, Krishna Sitaram, Shilpa K. Srinivas
  • Patent number: 9572064
    Abstract: Systems and methods are described for scheduling transmissions from an access node. A location may be determined for a plurality of small cells within an access node signal area. Based on the determined locations, a scheduling algorithm may be selected for the access node, where the scheduling algorithm may comprise one of a low proportional fairness scheduling algorithm, a medium proportional fairness scheduling algorithm, and a high proportional fairness scheduling algorithm. Data may then be transmitted from the access node to a plurality of wireless devices based on the selected scheduling algorithm.
    Type: Grant
    Filed: August 8, 2014
    Date of Patent: February 14, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Hemanth Pawar, Shilpa Kowdley, Krishna Sitaram, Daniel Vivanco
  • Patent number: 9565676
    Abstract: Methods and systems for providing a mobility-limited user equipment device (UE) are disclosed. While a first base station serves a UE in a first coverage area on a first carrier, either the first base station or the UE makes a first determination that the UE is substantially stationary. Responsive to at least making the first determination, the first base station causes the UE to receive service on a second carrier concurrently with the first base station continuing to serve the UE in the first coverage area on the first carrier. By way of example, the first base station may provide the second carrier in the first coverage area, or a second base station may provide the second carrier in a second coverage area.
    Type: Grant
    Filed: December 19, 2014
    Date of Patent: February 7, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Pratik Kothari, Parashar Thanki, Hemanth B. Pawar, Krishna Sitaram
  • Patent number: 9560562
    Abstract: Systems and methods are described for determining a handover condition in a wireless communication network. A plurality of active wireless devices in communication with a first access node may be detected. Measurement and reporting information may be received at the first access node from the wireless devices indicating proximity to a second access node. A criteria for selecting a wireless device in communication with the first access node for handover may be determined. A bias factor for the selected wireless device based on the received measurement and reporting information may be calculated. The bias factor may be provided to the selected wireless device and the first access node and/or a controller node may instruct the selected wireless device to communicate with the second access node.
    Type: Grant
    Filed: June 26, 2014
    Date of Patent: January 31, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Daniel Vivanco, Krishna Sitaram, Chunmei Liu, Hemanth Pawar
  • Patent number: 9554375
    Abstract: Coordinated multipoint (CoMP) may involve coordination between multiple sectors to receive and/or process a given user equipment's uplink signal. Embodiments herein may help to intelligently select the particular sectors that should coordinate to provide uplink CoMP, based on the types of applications being served in sectors that are candidates to provide uplink CoMP. For example, a base station serving a primary sector in an CoMP group that includes two or more candidates from which to select a secondary sector sectors for uplink CoMP, may evaluate the application being served by traffic flows in these candidates, in an effort to select secondary sectors having lower-priority traffic flows.
    Type: Grant
    Filed: May 1, 2015
    Date of Patent: January 24, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Shilpa Kowdley Srinivas, Hemanth Pawar, Krishna Sitaram, Chunmei Liu, Siddharth Oroskar, Jasinder Singh
  • Patent number: 9554367
    Abstract: Systems and methods are described for determining an access node for a wireless device. An increased signal level for a first signal and an adjustment value based on the increased signal level may be determined. An indication of the adjustment value and the first signal may be transmitted from a first access node. A wireless device in communication with the first access node may transmit signal information comprising a first signal level associated with the first access node and a second signal level associated with a second access node, where the signal information is transmitted in response to a reporting event triggered at the wireless device based on the adjustment value and at least one of a received signal level for the first signal and a received signal level for the second signal. Based on the signal information, one of the first access node and the second access node may be selected for communication with the wireless device.
    Type: Grant
    Filed: May 5, 2014
    Date of Patent: January 24, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Chunmei Liu, Daniel Vivanco, Krishna Sitaram
  • Patent number: 9544097
    Abstract: Systems and methods for operating a wireless communication system are provided. An access node can receive a multimedia broadcast multicast services data flow. The data flow can comprise a first data packet and a second data packet where the first data packet comprises a first transmission time and the second data packet comprises a second transmission time. The data flow can be stored in a buffer of the access node. The first data packet can be transmitted from the access node to a wireless device at the first transmission time and the access node can receive a retransmission request to retransmit the first data packet. The access node can determine an anticipated packet retransmission time based on when the access node received the request to retransmit the first data packet. The access node can retransmit the first data packet to the wireless device based on the anticipated packet retransmission time.
    Type: Grant
    Filed: August 20, 2013
    Date of Patent: January 10, 2017
    Assignee: Sprint Spectrum L.P.
    Inventors: Daniel Vivanco, Krishna Sitaram
  • Patent number: 9538486
    Abstract: A method, system, and medium are provided for dynamically activating and deactivating power boosting operations in a mobile communications network. A determination of whether a power boosting operation is appropriate or not is made based on the network's coverage contiguity characteristics. Power boosting operations are activated when the network exhibits contiguous coverage and deactivated when the network's coverage is non-contiguous.
    Type: Grant
    Filed: January 7, 2016
    Date of Patent: January 3, 2017
    Assignee: Sprint Communications Company L.P.
    Inventors: Krishna Sitaram, Daniel Alberto Vivanco, Chunmei Liu
  • Patent number: 9503948
    Abstract: First data packets for a wireless device are received from a data source at a network element, and are encoded into at least one second data packet using a data redundancy factor, where the at least one second data packet comprising at least two of the first data packets. The at least one second data packet is provided to an access node and is sent from the access node to the wireless device over a first frequency band. A round trip time of at least one of the first data packets is determined at the data source, and further a frequency band load of the first frequency band is determined. A handover is performed of the wireless device from the first frequency band to a second frequency band based on the round trip time and the frequency band load of the first frequency band.
    Type: Grant
    Filed: March 4, 2014
    Date of Patent: November 22, 2016
    Assignee: Sprint Spectrum L.P.
    Inventors: Daniel Vivanco, Krishna Sitaram