Patents Represented by Attorney Nutter McClelnnen & Fish LLP
  • Patent number: 7649953
    Abstract: The present invention achieves differential transmit diversity and related diversity reception schemes transmit symbol constellations which are extended to multiple levels. Heretofore, a group of transmission bits is divided into a first sub-group of transmission bits and a second sub-group of transmission bits. Then, the first sub-group of transmission bits is mapped (14) onto constellation points of a differential transmit diversity coding scheme from an orthogonal design for coding of the first sub-group of transmission bits. Then, after differential encoding of the constellation points (32, 34, 36, 40) a length of the transmission symbol vector is scaled (38) for coding the second sub-group of transmission bits. Therefore, the present invention overcomes restrictions implied through unit length requirements for previously known differential transmit diversity schemes from orthogonal designs.
    Type: Grant
    Filed: February 13, 2003
    Date of Patent: January 19, 2010
    Assignee: NTT DoCoMo, Inc.
    Inventor: Gerhard Bauch