摘要 |
A method and apparatus are presented for transmitting a multicarrier signal, wherein said signal is of the offset quadrature amplitude modulation, OQAM, type comprising symbols in the time-frequency space, wherein the symbols include a data containing symbol and a precoding symbol, wherein the precoding symbol is selected to carry data in both the in-phase and quadrature components of the data containing symbol, when received by a receiver. An Alamouti like space-time coding (or transmit diversity) is applied to a Filter Bank Multicarrier (FBMC) transmission using Offset QAM (OQAM). In FBMC, due to the orthogonality in the real domain only, an intrinsic interference results thereof for the imaginary component. The intrinsic interference terms are not equivalent at each antenna since it depends on the surrounding symbols. The application proposes to use a precoding symbol chosen to cancel out (zero) the intrinsic interference individually for each antenna, ie a code rate of 1/2 (sending one data symbol requires two time units). A more elaborated embodiment proposes to choose the contiguous precoding symbols such that a virtual QAM Alamouti scheme is achieved, without rate loss. |