Patents by Inventor Lei Wan

Lei Wan 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: 20110064036
    Abstract: In a method for improved HARQ retransmissions of data streams in a node in a MIMO wireless communication system, transmitting S1 data across a plurality of available MIMO links according to a predetermined rank and radio resource allocation, receiving S2 a retransmission request for at least part of the transmitted data, reducing the rank S3 of the retransmissions by selecting a subset of the plurality of available MIMO links. Subsequently, adaptively reallocating S4 available radio resources to the selected subset, and retransmitting S5 the requested data on said selected subset according to the reduced rank and radio resource re-allocation.
    Type: Application
    Filed: November 30, 2007
    Publication date: March 17, 2011
    Inventors: Shiau-He Tsai, Lei Wan
  • Publication number: 20110065468
    Abstract: The available transmission resources on a downlink-shared channel are divided into resource blocks, each resource block comprising a predetermined number of sub-carriers during a predetermined time period. The resource blocks are subdivided into localized resource blocks and distributed resource blocks. A user requiring sufficient resources can be allocated a plurality of said localized resource blocks. A user who would require only a small number of said localized resource blocks can instead be allocated subunits of a plurality of said distributed resource blocks.
    Type: Application
    Filed: January 18, 2007
    Publication date: March 17, 2011
    Inventors: Stefan Parkvall, Erik Dahlman, Lei Wan
  • Publication number: 20100322330
    Abstract: The present invention relates to a method and arrangements in a communication system for Multi User Multiple-Input-Multiple-Output (MU-MIMO) signaling via Multiple-Input-Multiple-Output (MIMO) antennas between a base station and one of a plurality of mobile terminals supporting both Single User and Multi User Multiple-Input-Multiple-Output (SU-MIMO and MU-MIMO) signaling modes. Switching between the modes is supported in the system and the modes have partly shared signaling. SU-MIMO mode signaling which is redundant, i.e. not needed, for MU-MIMO mode signaling is identified. Bits, i.e. data bits, of the identified redundant signaling is re-interpreted or re-defined to comprise signaling information associated with MU-MIMO mode. The signaling information associated with MU-MIMO mode is signaled to the mobile terminal by using the reinterpreted redundant bits.
    Type: Application
    Filed: April 3, 2008
    Publication date: December 23, 2010
    Inventors: George Jongren, Bo Goransson, Lei Wan
  • Publication number: 20100325508
    Abstract: A method in a receiving node for sending an acknowledgement/not acknowledgement “ACK/NACK” feedback report of received data units over a radio link is provided. When the receiving node have received (301) data units in a number of subframes over a first radio link from a sending node, it creates (302) an ACK/NACK feedback report. The report is compressed such that it comprises one single ACK/NACK feedback relating to the data units in the number of received subframes, and the report comprises an indicator indicating said number of received subframes. The sending node then transmits (303) the created ACK/NACK feedback report to the sending node over a second radio link. The feedback report renders it feasible for the sending node to decide whether a retransmission of any subframe is required or not based on a comparison of the reported number of received subframes with the known transmitted number of subframes per frame, together with the compressed ACK/NACK feedback report.
    Type: Application
    Filed: November 7, 2008
    Publication date: December 23, 2010
    Inventors: Yang Hu, Lei Wan, Zhiyi Xuan
  • Publication number: 20100322100
    Abstract: The present invention ensures that the UEs are able to make use of all the available reference signals that can be used in a cell for performing UE measurements, estimations or demodulations. That is achieved by indicating on a downlink common or shared channel, the MIMO mode settings associated with a specific network node. The indicated MIMO mode settings explicitly or implicitly indicate available common reference signals and/or dedicated reference signals to be used for said UE measurements, estimations or demodulations, which implies that measurements, estimations or demodulations can be performed based on said received indication.
    Type: Application
    Filed: January 28, 2009
    Publication date: December 23, 2010
    Applicant: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
    Inventors: Lei Wan, David Astely, Muhammad Kazmi
  • Publication number: 20100323739
    Abstract: The invention relates to control of link resources in a wireless telecommunications system, in which instant channel feedback information is transmitted from a mobile terminal in response to receipt of a selection message from a basestation, and the instant channel feedback information is used for real-time resource allocation and adaptation at the basestation. The feedback information includes channel quality information derived from pilot signals and from pre-allocated transmission weights.
    Type: Application
    Filed: December 27, 2006
    Publication date: December 23, 2010
    Inventors: Lei Wan, Bo Göransson
  • Publication number: 20100278138
    Abstract: In a method of enabling synchronization for a channel in an OFDM based telecommunication system initially providing a symbol for transmission and selecting at least two carrier frequencies, subsequently determining a respective weighting parameter for the selected frequencies and finally transmitting the symbol on all selected frequencies based on the weighting parameters.
    Type: Application
    Filed: January 9, 2007
    Publication date: November 4, 2010
    Inventors: Johan Nyström, Magnus Almgren, Lei Wan
  • Patent number: 7817972
    Abstract: In a method for power control in a telecommunication system, the transmit power is adjusted based on at least the mutual information expression or a representation thereof. According to one aspect the transmit power for a coming slot is controlled based on the previously received slots, wherein an estimated quality is compared to a determined quality target based on the mutual information expression.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: October 19, 2010
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Lei Wan, Magnus Almgren, Claes Tidestav
  • Publication number: 20100220608
    Abstract: The present invention relates to methods and arrangements in a multi-antenna radio communication system, in particular to methods and arrangements for improved multiple HARQ transmission in such systems. While HARQ transmission schemes, as known in the art, only can consider the fact whether or not a transmission attempt has been successful the present invention provides a HARQ retransmission scheme that considers the reception quality for already performed transmissions of a same data packet when selecting a resource allocation for necessary re-transmissions. Resource allocation for retransmissions is based on a pre-defined metric indicating a quality of the reception of the previous transmission attempts. Such a metric can be derived from a quality measure derived in the receiver unit, e.g. a CQI or CSI-based value, or an appropriate measure of the mutual information, e.g. the accumulated conditional mutual information (ACMI).
    Type: Application
    Filed: March 20, 2007
    Publication date: September 2, 2010
    Inventors: Per Skillermark, Lei Wan, Jingyi Liao
  • Publication number: 20100195588
    Abstract: The invention relates to control of link resources in a wireless telecommunications system, in which instant channel feedback information is transmitted from a mobile terminal in response to receipt of a selection message from a basestation, and the instant channel feedback information is used for real-time resource allocation and adaptation at the basestation.
    Type: Application
    Filed: September 6, 2006
    Publication date: August 5, 2010
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventors: Lei Wan, Jingyi Liao, Yin Liu
  • Publication number: 20100165932
    Abstract: In a method of improved channel-dependent time- and frequency-domain scheduling in an OFDM based telecommunication system with multiple user terminals, determining SO a parameter value representative of the system load; pre-selecting SI a subset of user terminals if the determined parameter value is larger than or equal to a predetermined threshold; and performing S2 frequency-domain scheduling of the pre-selected subset, to reduce the downlink signaling overhead and enabling improved efficiency of the channel-dependent time- and frequency-domain scheduling.
    Type: Application
    Filed: August 17, 2006
    Publication date: July 1, 2010
    Applicant: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
    Inventors: Lei Wan, Yin Liu, Jingyi Liao
  • Publication number: 20100130223
    Abstract: Resources in a multi-cellular wireless communication system are scheduled. A beam pattern associated with at least one mobile terminal located within one of the cells is identified and assigned to a slot, providing at least one stream to said at least one mobile terminal. At least one other mobile terminal located within said cell having the same beam pattern associated therewith as that of said identified beam pattern to be served during said slot is scheduled. The assigned beam pattern in said cell is communicated to at least one interfering cell.
    Type: Application
    Filed: December 20, 2006
    Publication date: May 27, 2010
    Applicant: TELEFONAKTIEBOLAGET LM ERICSSON (PUMBL)
    Inventors: Jingyi Liao, Lei Wan
  • Publication number: 20100120441
    Abstract: A mechanism for increasing a sectorization order in a first sector of an antenna array. The object is achieved by a method in a network node. The network node and antenna array are comprised in a wireless communication system. The antenna array is deployed with a first sectorization. The network node comprises a first number of signal connections. Each signal connection is adapted to transmit and receive signals. The method comprises the step of splitting the first number of connections into a number of groups. Each one of the respective connection groups corresponds to one respective virtual sector resulting in a number of virtual sectors. The method further comprises the step of mapping the number of virtual sectors to the first sector, such that the first sector is split into the number of virtual sectors.
    Type: Application
    Filed: March 11, 2008
    Publication date: May 13, 2010
    Applicant: TELEFONAKTIEBOLAGET LM ERICSSON
    Inventors: Lei Wan, George Jöngren, David Astely
  • Patent number: 7697948
    Abstract: A method of adapting resource allocation parameters to reach one or more quality targets with improved accuracy is proposed. New information measurements based on the so-called mutual information, preferably at block-level, are introduced. The MI-based information measurements of a previous transmission, the channel prediction of a subsequent transmission and one or more quality requirements, are used to determine the amount and type of resources, e.g. time, frequency and power resources, that are to be used for the subsequent transmission. The resource allocation can for example comprise power allocation and/or link adaptation and the invention enables an advantageous implementation with cooperative link-adaptation and power allocation. The proposed method is useful in connection with ARQ/HARQ retransmissions.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: April 13, 2010
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Lei Wan, Magnus Almgren, Shiau-He Shawn Tsai
  • Publication number: 20100029292
    Abstract: The present invention relates to a method and apparatus for selecting radio resources for transmission of data over a radio link to which at least two resource units have been allocated. At least one resource unit is selected out of the allocated resource units, wherein the selection is determined in dependence of the result of checking whether values of a quality measure of the allocated resource units fall within a certain range.
    Type: Application
    Filed: November 9, 2005
    Publication date: February 4, 2010
    Inventors: Lei Wan, Magnus Almgren
  • Publication number: 20090296574
    Abstract: A method of allocating resources in a wireless multi-user network is disclosed, comprising the following steps: —performing a proportional fair scheduling in time and frequency domain based on the bitrate for each user and the channel quality measurements for each chunk per user; and—performing a power allocation in the following way: o if the traffic load is above a threshold: allocating the uniform power to all subcarriers o if the traffic load is below the threshold, adapting a channel-dependent power allocation scheme.
    Type: Application
    Filed: April 18, 2006
    Publication date: December 3, 2009
    Inventors: Jingyi Liao, Lei Wan
  • Publication number: 20090110087
    Abstract: Methods and apparatus are disclosed for scheduling sub-carriers in an Orthogonal Frequency Division Multiplexing (OFDM) communication system. In an exemplary method, channel quality metric values for each of a plurality of sub-channels are determined, in view of a selected mobile terminal. For each of two or more threshold levels for the channel quality metric, sub-carrier groups composed of sub-carriers corresponding to sub-channels having channel quality metric values superior to the threshold level are identified, and an estimated data throughput is calculated for each of the identified sub-carrier groups. One or more of the identified sub-carrier groups is allocated to the selected mobile terminal according to the estimated data throughputs.
    Type: Application
    Filed: October 30, 2007
    Publication date: April 30, 2009
    Inventors: Yin Liu, Lei Wan
  • Publication number: 20090046606
    Abstract: The present invention relates to an arrangement for point-to-point transmission over links between first and second link (end) terminals in a system implementing time division duplex (TDD) and wherein information is sent over the links in frames divided into time slots. It is adapted to determine the lengths of the frames on a per link basis using one or more link parameters, the frame length hence being variable.
    Type: Application
    Filed: July 1, 2005
    Publication date: February 19, 2009
    Inventors: Lei Wan, Lars Robert Loostrom, Qing Lin
  • Publication number: 20090036150
    Abstract: In a radio network a determination is made whether to implement cyclical delay diversity (CDD) for a radio frequency connection involving a radio base station (26) and a wireless terminal (30). The determination whether to implement cyclical delay diversity (CDD) is made in accordance with interference distribution at the wireless terminal (30), as such interference distribution is measured or otherwise perceived. When a determination is made to implement the cyclical delay diversity for the connection, plural transmit antennas (38) of the radio base station (26) are employed to implement the cyclical delay diversity for the connection. One or more indications of the interference distribution may be received and used to make the determination. The indication(s) of interference distribution can take the form of information received from the wireless terminal, and/or the form of frequency reuse plan information for interfering cells.
    Type: Application
    Filed: August 1, 2007
    Publication date: February 5, 2009
    Applicant: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Jingyi Liao, Lei Wan
  • Publication number: 20090013232
    Abstract: The present invention relates to automatic repeat request (ARQ) in wireless communication systems wherein a coded message block is spread over a plurality of sub-carriers or components. According to the invention an equalizing HARQ method is introduced. The equalizing HARQ identifies (215) and retransmits (230) the most distorted parts of a received coded message block. In addition, the retransmitted parts can optionally be relocated (225) to components of higher quality, which ensures good retransmission quality for those badly distorted parts in the prior transmission. After a soft-bit combination in a receiving node, the final received codeword experience an equalized quality variation with low multi-state performance loss.
    Type: Application
    Filed: December 30, 2005
    Publication date: January 8, 2009
    Inventors: Lei Wan, Jung-Fu Cheng