Patents by Inventor Xixian Chen

Xixian Chen 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: 10171146
    Abstract: Systems and methods for Multiple-Input and Multiple-Output (MIMO) rank reduction to improve downlink throughput are disclosed. A method of operation of a radio access node includes determining that an imbalance between parallel channels of a spatial multiplexing downlink transmission to a wireless device is greater than an imbalance threshold and/or that a Negative Acknowledgement (NACK) rate over time for the parallel channels of a spatial multiplexing downlink transmission reported by the wireless device is greater than a NACK rate threshold. The method also includes, in response to determining that the imbalance between the parallel channels is greater than the imbalance threshold and/or that the NACK rate is greater than the NACK rate threshold, performing a fast rank reduction for a next downlink transmission whereby a rank is reduced from a rank indicator reported by the wireless device to some lower rank. Reducing the rank may improve downlink throughput.
    Type: Grant
    Filed: February 16, 2015
    Date of Patent: January 1, 2019
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: James Jianfeng Weng, Hua Xu, Xixian Chen, Jianguo Long, Guoqiang Lu, Michael Roger, Ying Shao, Michel Chauvin
  • Patent number: 10021704
    Abstract: According to certain embodiments, methods and systems for toggling transmission parameters in a heterogeneous network to achieve a target block error rate by a network node may include obtaining a signal-to-noise ratio (SINR) estimate from channel quality information for a downlink between a network node and a wireless device. For each of a first code word and a second code word to be transmitted on the downlink, a block error rate estimate may be obtained based on the SINR estimate. The network node may then determine at least one expected SINR for the first code word and the second code word. The at least one expected SINR may be determined as a function of the SINR estimate and the block error rate estimate. Based on the at least one expected SINR for the first code word and the second code word, a modulation and coding scheme (MCS) for obtaining a target block error rate may be selected.
    Type: Grant
    Filed: October 29, 2014
    Date of Patent: July 10, 2018
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Chandra Sekhar Bontu, Jianguo Long, Xixian Chen
  • Patent number: 10015218
    Abstract: According to certain embodiments, methods and systems for providing broadcast multicast service include transmitting, by a network node, a first transmission of multicast content data to wireless devices at a first quality of service level and a second transmission of multicast content data to the wireless devices at a second quality of service level. The second quality of service level may be of a higher quality of service than the first quality of service. Feedback may be received from at least one wireless device in the broadcast service area. In response to the feedback from the wireless devices, one or more transmission parameters associated with a subsequent transmission of the multicast content data may be adjusted.
    Type: Grant
    Filed: October 20, 2014
    Date of Patent: July 3, 2018
    Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
    Inventors: Xixian Chen, Xiaoming Lai, Weigang Li
  • Patent number: 10003433
    Abstract: Systems and methods for control signal outer-loop adjustment are disclosed. In some embodiments, a method of operation of a network node in a cellular communications network is provided. The method includes transmitting a control signal and a data signal to a wireless device. The method also includes detecting an ambiguous state of reception of the control signal by the wireless device based on a feedback of reception of the data signal. The method also includes, in response to detecting the ambiguous state of reception, updating a link adaptation (LA) parameter used to choose a coding scheme and power level for transmission of information in the control signal. By updating the LA parameter in response to detecting the ambiguous state of reception, the network node may provide improved performance.
    Type: Grant
    Filed: November 14, 2014
    Date of Patent: June 19, 2018
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Xixian Chen, James Jianfeng Weng, Ahmed Nouah, Ying Shao
  • Publication number: 20180123748
    Abstract: A method for using a high order modulation (HoM) mode for communications with a wireless device in a wireless communication network is provided. The method includes receiving downlink channel quality indicator (CQI) information from an uplink transmission of the wireless device and determining a downlink channel quality estimate from the CQI information. When a measurement of the downlink channel quality estimate satisfies the predetermined criteria for a first predetermined number of consecutive uplink transmissions from the wireless device, a downlink transmission mode of the wireless device is switched from a first modulation mode to the HoM mode.
    Type: Application
    Filed: December 19, 2017
    Publication date: May 3, 2018
    Inventors: Chandra Sekhar BONTU, Xixian CHEN, Kevin LUO, Hong REN, Hua XU
  • Patent number: 9907111
    Abstract: A mobile phone network node may determine traffic load associated with a mobile phone network and initiate discontinuous transmission at a frame level, based at least in part upon, determining that the traffic load is less than a first threshold. The mobile phone network node may further initiate discontinuous transmission at a subframe level, based at least in part upon, determining that the traffic load is greater than the first threshold and less than a second threshold and initiate discontinuous transmission at a symbol level, based at least in part upon, determining that the traffic load is greater than the second threshold.
    Type: Grant
    Filed: December 3, 2015
    Date of Patent: February 27, 2018
    Assignee: Telefonaktiebolaget LM Ericsson (Publ)
    Inventors: Weigang Li, Xiaoming Lai, Xixian Chen
  • Patent number: 9887827
    Abstract: In one embodiment, a method of operating a radio access node is provided. The method comprises determining whether support from a secondary cell is required for a wireless device to communicate with the radio access node, and, in response to determining that support from the secondary cell is required, calculating a modified channel condition outer-loop value for the secondary cell; and using the modified channel condition outer-loop value in an initial activation decision step for the secondary cell. The initial activation decision step may comprise activating the secondary cell in response to determining that the sum of a device reported channel condition value and the modified channel condition outer-loop value is above an activation threshold. Corresponding devices, computer programs and radio access nodes adapted to carry out the methods provided are also disclosed.
    Type: Grant
    Filed: March 16, 2015
    Date of Patent: February 6, 2018
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Ping Yu, Peter Hazy, Xixian Chen, James Jianfeng Weng, Ying Shao, Patrick Lie Chin Cheong, Guoqiang Lu, Hong Yu
  • Publication number: 20180026688
    Abstract: Systems and methods for Multiple-Input and Multiple-Output (MIMO) rank reduction to improve downlink throughput are disclosed. A method of operation of a radio access node includes determining that an imbalance between parallel channels of a spatial multiplexing downlink transmission to a wireless device is greater than an imbalance threshold and/or that a Negative Acknowledgement (NACK) rate over time for the parallel channels of a spatial multiplexing downlink transmission reported by the wireless device is greater than a NACK rate threshold. The method also includes, in response to determining that the imbalance between the parallel channels is greater than the imbalance threshold and/or that the NACK rate is greater than the NACK rate threshold, performing a fast rank reduction for a next downlink transmission whereby a rank is reduced from a rank indicator reported by the wireless device to some lower rank. Reducing the rank may improve downlink throughput.
    Type: Application
    Filed: February 16, 2015
    Publication date: January 25, 2018
    Inventors: James Jianfeng Weng, Hua Xu, Xixian Chen, Jianguo Long, Guoqiang Lu, Michael Roger, Ying Shao, Michel Chauvin
  • Patent number: 9871642
    Abstract: A method for using a high order modulation (HoM) mode for communications with a wireless device in a wireless communication network is provided. The method includes receiving downlink channel quality indicator (CQI) information from an uplink transmission of the wireless device and determining a downlink channel quality estimate from the CQI information. When a measurement of the downlink channel quality estimate satisfies the predetermined criteria for a first predetermined number of consecutive uplink transmissions from the wireless device, a downlink transmission mode of the wireless device is switched from a first modulation mode to the HoM mode.
    Type: Grant
    Filed: June 25, 2015
    Date of Patent: January 16, 2018
    Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
    Inventors: Chandra Sekhar Bontu, Xixian Chen, Kevin Luo, Hong Ren, Hua Xu
  • Publication number: 20170181180
    Abstract: Various embodiments provide for the management of wireless resources, which can reduce call blocking by allowing high priority services, under suitable conditions, to use resources allocated to low priority services. Thus high priority services can pre-empt the usage of wireless resources by low priority services. This has the advantage of reducing call blocking for high priority calls, while permitting low priority calls to have more access to radio resources than conventional systems with the same call blocking rate. Thus a base station can implement a preemption mechanism that would reclaim Walsh Code and Forward Power resources from an active Supplemental Channel (SCH) burst in order to accommodate incoming Fundamental Channel (FCH) requests.
    Type: Application
    Filed: March 1, 2017
    Publication date: June 22, 2017
    Applicant: Microsoft Technology Licensing, LLC
    Inventors: Xixian Chen, Xiao-Dong Li, James Weisert, Qiang Yuan, Miroslav Budic
  • Publication number: 20170141885
    Abstract: A method for using a high order modulation (HoM) mode for communications with a wireless device in a wireless communication network is provided. The method includes receiving downlink channel quality indicator (CQI) information from an uplink transmission of the wireless device and determining a downlink channel quality estimate from the CQI information. When a measurement of the downlink channel quality estimate satisfies the predetermined criteria for a first predetermined number of consecutive uplink transmissions from the wireless device, a downlink transmission mode of the wireless device is switched from a first modulation mode to the HoM mode.
    Type: Application
    Filed: June 25, 2015
    Publication date: May 18, 2017
    Applicant: Telefonaktiebolaget LM Erisson (Publ)
    Inventors: Chandra Sekhar BONTU, Xixian CHEN, Kevin LUO, Hong REN, Hua XU
  • Patent number: 9596692
    Abstract: Various embodiments provide for the management of wireless resources, which can reduce call blocking by allowing high priority services, under suitable conditions, to use resources allocated to low priority services. Thus high priority services can pre-empt the usage of wireless resources by low priority services. This has the advantage of reducing call blocking for high priority calls, while permitting low priority calls to have more access to radio resources than conventional systems with the same call blocking rate. Thus a base station can implement a preemption mechanism that would reclaim Walsh Code and Forward Power resources from an active Supplemental Channel (SCH) burst in order to accommodate incoming Fundamental Channel (FCH) requests.
    Type: Grant
    Filed: April 30, 2014
    Date of Patent: March 14, 2017
    Assignee: Microsoft Technology Licensing, LLC
    Inventors: Xixian Chen, Xiao-Dong Li, James Weisert, Qiang Yuan, Miroslav Budic
  • Patent number: 9578583
    Abstract: Methods and apparatus are disclosed for handing over of a high-speed mobile terminal or user equipment from a source network node to a target network node. Reliable methods for measuring the speed of a moving user equipment are disclosed. Parameters used in a handover procedure are also adjusted in accordance with the speed of the user equipment. For handing over a high-speed user equipment, the present application discloses that the source network node can coordinate with the target network node and other candidate network nodes in transmitting a handover command to prevent handover failures.
    Type: Grant
    Filed: August 12, 2013
    Date of Patent: February 21, 2017
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Xiaoming Lai, Xixian Chen, Weigang Li
  • Publication number: 20170034758
    Abstract: Methods and apparatus are disclosed for handing over of a high-speed mobile terminal or user equipment from a source network node to a target network node. Reliable methods for measuring the speed of a moving user equipment are disclosed. Parameters used in a handover procedure are also adjusted in accordance with the speed of the user equipment. For handing over a high-speed user equipment, the present application discloses that the source network node can coordinate with the target network node and other candidate network nodes in transmitting a handover command to prevent handover failures.
    Type: Application
    Filed: October 14, 2016
    Publication date: February 2, 2017
    Inventors: Xiaoming Lai, Xixian Chen, Weigang Li
  • Patent number: 9496939
    Abstract: A node (28) of a radio access network (20) communicates over a radio interface (32) with a wireless terminal (30). The node (28) comprises a transmitter (34) and a controller (40). The transmitter (34) selectively operates in plural multiple input multiple output (MIMO) modes for downlink transmission over the radio interface (32). The controller (40) uses both a terminal speed value and a throughput value to make a determination when to switch between the plural multiple input multiple output (MIMO) modes for communicating with the wireless terminal. The plural MIMO modes comprise a first mode and a second mode. In the first mode open loop MIMO operates with cyclical diversity delay. In the second mode open loop MIMO operates without cyclical diversity delay. Although operating in open loop MIMO, advantages such as those of closed loop MIMO are realized.
    Type: Grant
    Filed: May 18, 2015
    Date of Patent: November 15, 2016
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Xixian Chen, Peter Deane, Xiaoming Lai
  • Publication number: 20160278102
    Abstract: According to certain embodiments, methods and systems for toggling transmission parameters in a heterogeneous network to achieve a target block error rate by a network node may include obtaining a signal-to-noise ratio (SINR) estimate from channel quality information for a downlink between a network node and a wireless device. For each of a first code word and a second code word to be transmitted on the downlink, a block error rate estimate may be obtained based on the SINR estimate. The network node may then determine at least one expected SINR for the first code word and the second code word. The at least one expected SINR may be determined as a function of the SINR estimate and the block error rate estimate. Based on the at least one expected SINR for the first code word and the second code word, a modulation and coding scheme (MCS) for obtaining a target block error rate may be selected.
    Type: Application
    Filed: October 29, 2014
    Publication date: September 22, 2016
    Inventors: Chandra Sekhar Bontu, Jianguo Long, Xixian Chen
  • Publication number: 20160277172
    Abstract: In one embodiment, a method of operating a radio access node is provided. The method comprises determining whether support from a secondary cell is required for a wireless device to communicate with the radio access node, and, in response to determining that support from the secondary cell is required, calculating a modified channel condition outer-loop value for the secondary cell; and using the modified channel condition outer-loop value in an initial activation decision step for the secondary cell, The initial activation decision step may comprise activating the secondary cell in response to determining that the sum of a device reported channel condition value and the modified channel condition outer-loop value is above an activation threshold. Corresponding devices, computer programs and radio access nodes adapted to carry out the methods provided are also disclosed.
    Type: Application
    Filed: March 16, 2015
    Publication date: September 22, 2016
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Ping YU, Peter HAZY, Xixian CHEN, James Jianfeng WENG, Ying SHAO, Patrick LIE CHIN CHEONG, Guoqiang LU, Hong YU
  • Publication number: 20160261365
    Abstract: Systems and methods for control signal outer-loop adjustment are disclosed. In some embodiments, a method of operation of a network node in a cellular communications network is provided. The method includes transmitting a control signal and a data signal to a wireless device. The method also includes detecting an ambiguous state of reception of the control signal by the wireless device based on a feedback of reception of the data signal. The method also includes, in response to detecting the ambiguous state of reception, updating a link adaptation (LA) parameter used to choose a coding scheme and power level for transmission of information in the control signal. By updating the LA parameter in response to detecting the ambiguous state of reception, the network node may provide improved performance.
    Type: Application
    Filed: November 14, 2014
    Publication date: September 8, 2016
    Inventors: Xixian Chen, James Jianfeng Weng, Ahmed Nouah, Ying Shao
  • Publication number: 20160241615
    Abstract: According to certain embodiments, methods and systems for providing broadcast multicast service include transmitting, by a network node, a first transmission of multicast content data to wireless devices at a first quality of service level and a second transmission of multicast content data to the wireless devices at a second quality of service level. The second quality of service level may be of a higher quality of service than the first quality of service. Feedback may be received from at least one wireless device in the broadcast service area. In response to the feedback from the wireless devices, one or more transmission parameters associated with a subsequent transmission of the multicast content data may be adjusted.
    Type: Application
    Filed: October 20, 2014
    Publication date: August 18, 2016
    Inventors: Xixian Chen, Xiaoming LAI, Weigang LI
  • Patent number: 9380576
    Abstract: An apparatus for allocating radio resources shared among a plurality of network operators is provided. Each network operator has at least one scheduling entity, SE, and a respective resource allocation, RA, probability for being selected for radio resource allocation during a transmission time interval, TTI. The apparatus includes a processor and a memory. The memory contains instructions executable by the processor that are configured to cause the apparatus, within a TTI, to select a network operator of the plurality of network operators for resource allocation within the TTI based at least in part on the RA probability of the network operator, allocate radio resources to an SE of the selected network operator within the TTI and update the RA probability of selecting each of the plurality of network operators for a next selection of resource allocation.
    Type: Grant
    Filed: May 1, 2014
    Date of Patent: June 28, 2016
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Weigang Li, Xiaoming Lai, Xixian Chen