| 摘要 |
The incident signal contains a preamble including a training sequence having a series of pulses whose polarity and time shifts are defined by respective polarity code and time-hopping code. The method comprises a digital cross-correlation of the received signal with said training sequence, said cross-correlation step (101) including algebraically summing in accordance with said polarity code (aj), windows of said received signal, the starting points of said windows being determined by said time-hopping code (cj), and a detection step for detecting the end point (nsynchro) of the preamble from the result of said cross-correlation step. When the size of the receiving buffer, i.e. the size of the window is smaller than the number N of samples of each replica of the training sequence, it is particularly advantageous that said digital cross-correlation step be performed iteratively in a block-by-block fashion, the computation of each block being split into M slices which are computed by algebraically summing windows N/M samples long. <IMAGE>
|
