| 摘要 |
A rotationally invariant, multilevel coded modulation scheme is provided by partitioning a constellation, such as an M-PSK or QAM constellation, into several trellis subsets, each of which is further partitioned into block subsets. The input bits are then encoded to select a signal point from the constellation. A first portion of the input bits are differentially encoded. A second portion of the input bits, together with at least one of the differentially encoded bits, are trellis encoded to select a trellis subset of the constellation. A third portion of the input bits - excluding any differentially encoded bits - are block encoded to select a block subset from the selected trellis subset. A fourth portion of the input bits, together with the remaining differentially encoded bits, are used to select a signal point from the selected block subset. <IMAGE> |
