| 摘要 |
<p>A scheme is presented for determining the first significant path (FSP) of a received multipath signal, from data defining the relative delay and the amplitude of the individual signal paths occurring in a series of time frames. The scheme includes filtering the data to spread the signal paths, performing a persistence test between frames to reject spurious signal paths, combining the energy of the signal paths in a frame, applying a test to determine the time at which the combined energy satisfies a criterion, and selecting the FSP dependent on that time. The combined energy may be evaluated within a sliding window, and the position of the window within the frame determined that maximises the combined energy. Alternatively, the combined energy may be evaluated as the cumulative energy through the frame, and the position determined at which the cumulative energy reaches a threshold. In this latter case, the time of the FSP may be biased depending on the delay spread of the signal paths. Reporting of the time of the FSP in successive frames may be subject to hysteresis to reduce jitter, and may be subject to a maximum change.</p> |
