| 摘要 |
A method for reception of DVB-H signals wherein a MPEG transport stream is grouped into packets belonging to a certain IP data stream and forming bursts in time slices, the MPEG-TS is modulated into OFDM symbols, these symbols are grouped in frames, the frames themselves are grouped in superframes and symbols, frames and superframes are provided with numbers, whereas a transmitter does not change the transmission parameters (FFT mode, guard interval, code rate, modulation format) between successive bursts and a receiver is notified about a relative time from a first burst to transmission of the next burst and the receiver is switched off between the first and the next burst comprising: accurately calculating the receive time of the next burst from the DVBH delta-t time received in the first burst; setting a wake up timer and powering down the receiver; powering up the receiver for reception of the next burst exactly at the superframe boundary; executing signal acquisition; calculating the symbol number and frame number of the first symbol that contains relevant data to be modulated within the actual superframe; calculation the number of bis to be discarded from the MPEG-TS to align with a boundary of a MPEG-TS-packet; discarding the bits; and starting demodulation at the boundary of the MPEG-TS-packet. |
