| 摘要 |
The invention proposes frames of OFDM symbols (see Fig. 5), possibly for use in DVB systems dealing with both static and mobile receivers. The frames commence with a symbol including control signalling and possibly reference symbol sequences for frame synchronisation 406. These control signals may have reduced numbers of sub-carriers compared with the payload data symbols 402/404 and consequently shorter durations in the time domain. Hence a larger guard interval fraction (10c) is selected to ensure that the guard interval is adequate (unlike 10b). |
