| 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 äC32(1), C32(2)ü and äC64(1), C64(2), C64(3), C64(4)ü, 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 äC32(1), C32 (2)ü, and four times (= 2<2>) that of the data transmitted using the sequences äC64(1), C64(2), C64(3), C64(4)ü. The C16(1), however, cannot be selected if any one of its lower level sequences äC32(1), C32(2)ü and äC64(1), C64(2), C64(3), C64(4)ü 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. <IMAGE></p> |
