Patents by Inventor Liyu Cai

Liyu Cai 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: 20210376861
    Abstract: Embodiments of the present disclosure relate to a method, device and computer readable medium for interleaving data in a wireless communication system. The method described herein comprises determining, based on a first number of bits in a bit sequence to be interleaved, a second number of rows in a triangular interleaver for interleaving the bits. The method also comprises dividing the bit subsequence into the second number of subsequences associated with the rows, a difference between numbers of bits in any two successive subsequences of the subsequences being a predetermined value. The method further comprises writing the second number of subsequences into the triangular interleaver in an order of the rows, the writing comprising, for a given row in the triangular interleaver, determining, based on an index of the given row, a writing order of bits having odd indexes and bits having even indexes in a subsequence associated with the given row.
    Type: Application
    Filed: September 13, 2018
    Publication date: December 2, 2021
    Applicant: Nokia Technologies Oy
    Inventors: Kai Zhu, Yu Chen, Liyu Cai
  • Publication number: 20210367711
    Abstract: Embodiments of the present disclosure relate to a method and device for interleaving data in a wireless communication system.
    Type: Application
    Filed: September 10, 2018
    Publication date: November 25, 2021
    Applicant: Nokia Technologies Oy
    Inventors: Kai Zhu, Yu Chen, Liyu Cai
  • Publication number: 20210289472
    Abstract: Embodiments of the present disclosure provide a communication method and apparatus. For example, at a first device, a resource for data transmission is randomly selected, and the resource is used to transmit data. In addition, the first device sends, to a second device, an indication that the first device will continue to use the resource for transmitting further data. A corresponding apparatus is further disclosed in the present disclosure.
    Type: Application
    Filed: July 25, 2017
    Publication date: September 16, 2021
    Applicants: Alcatel Lucent, Nokia Solutions and Networks Oy
    Inventors: Yong LIU, Liyu CAI, Torsten WILDSCHEK
  • Publication number: 20210274009
    Abstract: Embodiments of the present disclosure provide methods, apparatuses and computer program for content pushing service in a wireless mobile communication system. In one embodiment, the method comprises receiving a proactive pushing service request from an internet content provider; determining, for the proactive pushing service request, a proactive pushing strategy based on auxiliary information predetermined for network optimization processing; and sending, to at least one network element in the wireless mobile communication system, a command for the proactive pushing service so that at least a part of internet contents designated by the proactive pushing service request are proactively pushed to one or more users based on the determined proactive pushing strategy.
    Type: Application
    Filed: June 25, 2018
    Publication date: September 2, 2021
    Inventors: He WANG, Wenyi XU, Liyu CAI
  • Patent number: 10554763
    Abstract: The present invention discloses a method and an apparatus for a virtual base station migration in a BBU pool which has multiple baseband units. The migration method comprises the following steps performed by a first virtual base station: measuring an available bandwidth between the first virtual base station and a second virtual base station, wherein the first virtual base station and the second virtual base station belong to different baseband units in the BBU pool; estimating a service interruption time of the first virtual base station; selecting a migration mechanism of the first virtual base station according to the estimated service interruption time. The migration mechanism comprises configuring a common measurement gap for user devices of the first virtual base station, or configuring random access time slots for user devices of the first virtual base station, or configuring a discontinuous receiving cycle for user devices of the first virtual base station.
    Type: Grant
    Filed: April 10, 2015
    Date of Patent: February 4, 2020
    Assignee: ALCATEL LUCENT
    Inventors: Cheng Wang, Yun Deng, Liyu Cai
  • Publication number: 20170054817
    Abstract: The present invention discloses a method and an apparatus for a virtual base station migration in a BBU pool which has multiple baseband units. The migration method comprises the following steps performed by a first virtual base station: measuring an available bandwidth between the first virtual base station and a second virtual base station, wherein the first virtual base station and the second virtual base station belong to different baseband units in the BBU pool; estimating a service interruption time of the first virtual base station; selecting a migration mechanism of the first virtual base station according to the estimated service interruption time. The migration mechanism comprises configuring a common measurement gap for user devices of the first virtual base station, or configuring random access time slots for user devices of the first virtual base station, or configuring a discontinuous receiving cycle for user devices of the first virtual base station.
    Type: Application
    Filed: April 10, 2015
    Publication date: February 23, 2017
    Applicant: Alcatel Lucent
    Inventors: Cheng Wang, Yun Deng, Liyu Cai
  • Publication number: 20160119831
    Abstract: The present invention provides a method of determining mobility of a user equipment having dual connectivity in a communication system. In one embodiment, the user equipment transmits measurement reports in a frequency occupied by the source small cell to the source small cell, such that the source small cell determines that a target small cell replaces itself to serve the user equipment. In another embodiment, the user equipment transmits measurement reports in a frequency occupied by the source small cell to the macro cell, such that the macro cell determines that a target small replaces the source small cell to serve the user equipment.
    Type: Application
    Filed: May 13, 2013
    Publication date: April 28, 2016
    Applicant: Alcatel Lucent
    Inventors: Yun Deng, Liyu Cai
  • Patent number: 8964869
    Abstract: The present invention provides a pre-coding method in a multi-user macro-diversity transmission system. The method comprises: obtaining, for a mobile station in the multi-user macro-diversity transmission system, a first sub-precoder that guarantees orthogonality between equivalent channels of users; obtaining a second sub-precoder by performing QR decomposition based on equivalent channels precoded through the first sub-precoder; obtaining a final pre-coder with respect to the mobile station by combining the first sub-precoder and the second sub-precoder; and performing pre-coding on data of the mobile station with the final precoder The present invention further provides a corresponding base station and a multi-user macro-diversity transmission system. Through the technical solution of the present invention, the multi-user macro-diversity transmission system may achieve more macro-diversity gain, thereby greatly enhancing the performance of the multi-user macro-diversity transmission.
    Type: Grant
    Filed: August 18, 2009
    Date of Patent: February 24, 2015
    Assignee: Alcatel Lucent
    Inventors: Dong Li, Liyu Cai
  • Patent number: 8867477
    Abstract: In a wireless network there is a scheduling method in which a base station (BS) acquires information relevant to signal quality between the BS and each mobile terminal and reports to a scheduling apparatus. The scheduling apparatus selects a service BS for each terminal and determines a specific BS to compensate for interference; and may provide further controls to correspondingly transmit service data of the terminal to the service BS. The BS determines the serviced terminal and the terminal of which the interference is eliminated. When servicing the terminal on a time-frequency resource and eliminating the interference from other BS, the BS may only acquire channel state information of the terminal associated with the BS to the BS on the corresponding time-frequency resource and calculate a pre-coded matrix, so as to pre-code terminal service data from the service BS and generate downlink signals to be transmitted.
    Type: Grant
    Filed: August 6, 2008
    Date of Patent: October 21, 2014
    Assignee: Alcatel Lucent
    Inventors: Yang Song, Liyu Cai
  • Patent number: 8718035
    Abstract: A method and device for performing Multi-Input Multi-Output transmission to a mobile terminal in the base station devices of a wireless communication system is provided. Each base station device determines the sector coordination group used at a certain frequency band according to system settings. Each base station device only performs multiple-sector (-cell) collaborative MIMO transmission in the sector coordination group which includes the sectors governed by the base station device. A simple and effective method is provided for realizing the multiple-sector (-cell) MIMO technology, its advantages including but not limited to there being a reduced amount of information exchanged between sectors (cells), which facilitates implementation and management, and good performance in controlling interface between sectors (cells).
    Type: Grant
    Filed: August 18, 2008
    Date of Patent: May 6, 2014
    Assignee: Alcatel Lucent
    Inventors: Keying Wu, Yang Song, Liyu Cai, Dong Li
  • Patent number: 8611905
    Abstract: A method and device for controlling the serving BS and at least one coordinating BS for coordinating downlink data communication with the MS in a wireless telecommunication network based on CO-MIMO technology. The method comprises obtaining the MIMO downlink channel information between the serving BS and the MS and between the coordinating BS and the MS, determining the downlink signal precoding information between the serving BS and the MS and between the coordinating BS and the MS according to the channel information, and performing MIMO downlink data communication coordinately with the MS based on the downlink signal precoding information.
    Type: Grant
    Filed: March 13, 2009
    Date of Patent: December 17, 2013
    Assignee: Alcatel Lucent
    Inventors: Xiaolong Zhu, Liyu Cai, Keying Wu, Hongwei Yang
  • Patent number: 8325842
    Abstract: A method for pre-processing data to be transmitted in a multiple-input communication system comprises the following steps: generating a beamforming matrix and a pre-coding matrix; combining the beamforming matrix and the pre-coding matrix to generate a weight matrix; and pre-processing the data by using the generated weight matrix. There are also provided a transmitter, a base station, and a communication system using the method.
    Type: Grant
    Filed: May 10, 2007
    Date of Patent: December 4, 2012
    Assignee: Alcatel Lucent
    Inventors: Xiaolong Zhu, Hongwei Yang, Liyu Cai
  • Patent number: 8248909
    Abstract: A method and device for the baseband process of space-time/space-frequency/spatial diversity transmitter in the SC-FDMA system, the device is characterized in that: 1) an encoding means is connected to the output end of the M-point DFT module; 2) a space-time encoding means, for encoding the corresponding symbol of at least two adjacent symbol sets, and outputting at least two data sets; each sub-carrier mapping means maps respectively each data set to the corresponding antenna, so that the mapped data satisfy the requirements: The symbols mapped on each antenna keep the same sequence as the M symbols outputted by the M-point DFT module; the mapped symbols keep the same sub-carrier interval; the M data of each mapped SC-FDMA symbol are the M outputted data of the DFT module, or the inverse of the M outputted data, or the complex conjugate of the M outputted data, or the inverse complex conjugate of the M outputted data.
    Type: Grant
    Filed: April 9, 2007
    Date of Patent: August 21, 2012
    Assignee: Alcatel Lucent
    Inventors: Dong Li, Guosong Li, Xialong Zhu, Hongwei Yang, Liyu Cai
  • Patent number: 8248993
    Abstract: The present invention discloses a distributed base station serving mobile stations, which comprises multiple antenna-RF processing units and a central processing unit remotely connected with said multiple antenna-RF processing units. Each of the antenna-RF processing units has an antenna array formed by multiple antennas.
    Type: Grant
    Filed: October 12, 2006
    Date of Patent: August 21, 2012
    Assignee: Alcatel Lucent
    Inventor: Liyu Cai
  • Patent number: 8238307
    Abstract: A Macro-Diversity HandOver (MDHO) solution based on multi-User MIMO is provided. Multiple base stations (BSs) serve the MDHO zone. By jointly precoding the modulated signals to be sent, the multiple BSs send the precoded signals to the multiple mobile stations (MSs) over the same time-frequency resources. The signal to be sent is transmitted to the multiple MSs in the MDHO zone. Due to the adoption of the precoding technique, each MS makes no or small interference to other MSs. Since the multiple BSs that serve one MDHO zone serve multiple MSs over the same time-frequency resources, the system capacity in the MDHO zone is greatly improved.
    Type: Grant
    Filed: August 13, 2008
    Date of Patent: August 7, 2012
    Assignee: Alcatel Lucent
    Inventors: Hongwei Yang, Liyu Cai, Keying Wu, Dong Li
  • Publication number: 20120052896
    Abstract: A mobile communication method, a base station and a mobile communication system employing a hierarchical virtual antenna architecture are disclosed. The method comprises steps of: negotiating, by a first base station, with a second base station about a transmission mode with a mobile station; and according to the negotiated transmission mode, negotiating, by the first base station, with the second base station about respective demodulation reference signal frequency pattern allocation and measurement reference signal frequency pattern allocation in the hierarchical virtual antenna architecture. The flexible and effective reference signals may be realized in various multi-cell Multiple-Input Multiple-Output (MIMO) operation modes by the method.
    Type: Application
    Filed: April 28, 2009
    Publication date: March 1, 2012
    Inventors: Dong Li, Liyu Cai
  • Publication number: 20120020319
    Abstract: The proposal for eliminating inter-cell interference based on cooperation with the prior base station has problems such as resources occupation and Backhaul load increment. The invention provides a multi-base station cooperative multiple-input multiple-output (MIMO) with low information interaction in a wireless network and a scheduling method and a device thereof.
    Type: Application
    Filed: August 6, 2008
    Publication date: January 26, 2012
    Inventors: Yang Song, Liyu Cai
  • Publication number: 20110142164
    Abstract: A method and device for performing Multi-Input Multi-Output transmission to a mobile terminal in the base station devices of a wireless communication system is provided. Each base station device determines the sector coordination group used at a certain frequency band according to system settings. Each base station device only performs multiple-sector (-cell) collaborative MIMO transmission in the sector coordination group which includes the sectors governed by the base station device. A simple and effective method is provided for realizing the multiple-sector (-cell) MIMO technology, its advantages including but not limited to there being a reduced amount of information exchanged between sectors (cells), which facilitates implementation and management, and good performance in controlling interface between sectors (cells).
    Type: Application
    Filed: August 18, 2008
    Publication date: June 16, 2011
    Inventors: Keying Wu, Yang Song, Liyu Cai, Dong Li
  • Publication number: 20110063989
    Abstract: A Macro-Diversity HandOver (MDHO) solution based on multi-User MIMO is provided. Multiple base stations (BSs) serve the MDHO zone. By jointly precoding the modulated signals to be sent, the multiple BSs send the precoded signals to the multiple mobile stations (MSs) over the same time-frequency resources. The signal to be sent is transmitted to the multiple MSs in the MDHO zone. Due to the adoption of the precoding technique, each MS makes no or small interference to other MSs. Since the multiple BSs that serve one MDHO zone serve multiple MSs over the same time-frequency resources, the system capacity in the MDHO zone is greatly improved.
    Type: Application
    Filed: August 13, 2008
    Publication date: March 17, 2011
    Inventors: Hongwei Yang, Liyu Cai, Keying Wu, Dong Li
  • Publication number: 20110028156
    Abstract: A method and device for controlling the serving BS and at least one coordinating BS for coordinating downlink data communication with the MS in a wireless telecommunication network based on CO-MIMO technology. The method comprises obtaining the MIMO downlink channel information between the serving BS and the MS and between the coordinating BS and the MS, determining the downlink signal precoding information between the serving BS and the MS and between the coordinating BS and the MS according to the channel information, and performing MIMO downlink data communication coordinately with the MS based on the downlink signal precoding information.
    Type: Application
    Filed: March 13, 2009
    Publication date: February 3, 2011
    Inventors: Xiaolong Zhu, Liyu Cai, Keying Wu, Hongwei Yang