| 摘要 |
<p>A CDMA communication method capable of providing a multi-rate user with high quality transmission using a spreading sequence selected from sequences which consist of multilayer sequences arranged in a hierarchical tree structure. A higher level sequence C16(1) and its inverted sequence C16(1) are included in its lower level sequences {C32(1), C32(2 and {C64(1), C64(2), C64(3), C64(4)}, for example, and a sequence from a higher level is selected to transmit a higher rate data: The C16(1) is used to transmit data whose peak rate is twice the peak rate of the data transmitted using its lower level sequences {C32(1), C32(2, and four times (= 2 2) that of the data transmitted using the sequences {C64(1), C64(2), C64(3), C64(4)}. The C16(1), however, cannot be selected if any one of its lower level sequences {C32(1), C32(2 and {C64(1), C64(2), C64(3), C64(4)} are already being used. This makes it possible for all the spreading sequences of simultaneous multi-rate users to be orthogonal at any transmission rate.</p> |
