| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve transmission efficiency regarding a transmitter using an antenna array and a space time code matrix. <P>SOLUTION: User signals U1 are mapped to modulation signal points (respective signal points of QPSK for instance) in a mapping part 1-1 and space time encoding is performed to the signal points by a quasi orthogonal space time encoding part 1-2. In the quasi orthogonal space time encoding part 1-2, a quasi orthogonal space time encoding matrix capable of utilizing beam decomposition characteristics and keeping orthogonality while obtaining the effect of beam synthesis though the number of rows is less than the one of a complete orthogonal space time encoding matrix is used. The output of the quasi orthogonal space time encoding part 1-2 is beam steering processed in a beam steering part 1-3, beam multiplexed in a synthesis part 1-4 and transmitted from the antenna array 1-5. In order to eliminate signal components generated by non- orthogonality on a reception side, the space time encoded output is allocated to the multiple beams of a low side lobe and transmitted and the orthogonality is maintained. <P>COPYRIGHT: (C)2003,JPO |
