Method and apparatus for transmitting data

1. A method comprising:

accessing a first stream of data;

dividing the first stream of data into a series of bursts;

transmitting from a transmitter the series of bursts over a continuous-mode transmission system during at least two fixed and periodic burst periods of time, the burst periods of time having a first common length of time determined prior to a first of the burst periods of time, wherein successively transmitted bursts in the series are separated in time so as to allow a receiver to enter and exit a power saving mode between receiving successively transmitted bursts, the power saving mode occurring during fixed and periodic power saving periods of time having a second common length of time determined prior to a first of the at least two burst periods of time;

accessing a second stream of data; and

transmitting portions of the second stream from the transmitter over the continuous-mode transmission system during a time interval during which at least part of the transmission of the first stream of data occurs, with successively transmitted portions in the second stream separated in time by respective time intervals having lengths that are not configured to allow the receiver to enter and to exit the power saving mode between receiving successively transmitted portions of the second stream, wherein the burst transmissions use a data structure that includes a synchronization segment containing data usable by a receiver to synchronize with the burst transmissions.

2. The method of claim 1 , wherein transmitting the second stream of data comprises transmitting the second stream of data according to a protocol that expects a receiver to remain on continuously while receiving the second stream of data.

3. The method of claim 1 , wherein transmitting the series of bursts and transmitting portions of the second stream both comprise transmitting in accordance with a vestigial side-band modulation format.

4. The method of claim 1 , wherein transmitting the series of bursts and transmitting portions of the second stream both comprise transmitting in accordance with the ATSC A/53 Digital Television Standard.

5. The method of claim 1 , wherein the second stream of data comprises content of a program, with the content of the program having been encoded and interleaved.

6. The method of claim 1 , wherein (1) the first stream of data includes data configured to be displayed at a first playback rate, (2) the second stream of data includes data configured to be displayed at a second playback rate, (3) a burst is transmitted at a rate substantially higher than the first playback rate, and (4) the second stream of data is transmitted at substantially the second playback rate.

7. The method of claim 1 , wherein at least one portion of the first stream of data is transmitted multiple times according to a predetermined schedule.

8. The method of claim 1 , further comprising separating the transmission of the bursts in the series by separation times of sufficient duration that a receiver can turn off and then on in between receiving successive bursts.

9. The method of claim 1 , further comprising determining the separation in time.

10. The method of claim 1 , wherein a burst in the series includes an indication of an expected transmission time of the next burst in the series.

11. The method of claim 1 , wherein the separation in time is of sufficient duration to permit the receiver, after receiving a burst in the series, then entering the power saving mode and then exiting the power saving mode, to reacquire a signal upon which the bursts are received and to receive the next burst in the series on the reacquired signal.

12. A system comprising:

a processor configured to receive a first stream of data and a second stream of data, and to divide the first stream of data into a series of bursts; and

a transmitter configured to simultaneously transmit over a continuous-mode transmission system (i) the series of bursts during at least two fixed and periodic burst periods of time, the burst periods of time having a first common length of time determined prior to a first of the burst periods of time, wherein successively transmitted bursts in the series are separated in time so as to allow a receiver to enter and exit a power saving mode between receiving successively transmitted bursts, the power saving mode occurring during fixed and periodic power saving periods of time having a second common length of time determined prior to a first of the at least two burst periods of time, wherein the burst transmissions use a data structure that includes a synchronization segment containing data usable by a receiver to synchronize with the burst transmissions, and (ii) portions of the second stream during a time interval during which at least part of the transmission of the first stream of data occurs, with successively transmitted portions in the second stream separated in time by respective time intervals having lengths that are not configured to allow the receiver to enter and to exit the power saving mode between receiving successively transmitted portions of the second stream.

13. The system of claim 12 , wherein (1) the first stream of data includes data configured to be displayed at a first playback rate, (2) the second stream of data includes data configured to be displayed at a second playback rate, (3) a burst is transmitted at a rate substantially higher than the first playback rate, and (4) the second stream of data is transmitted at substantially the second playback rate.

14. The system of claim 12 , wherein the transmitter is further configured to separate the transmission of the bursts in the series by separation times of sufficient duration that a receiver can turn off and then on in between receiving the bursts.

15. The system of claim 12 , wherein the processor is further configured to determine the separation time.

16. The system of claim 12 , wherein the transmitter is further configured to include in one or more bursts in the series an indication of an expected transmission time of the next burst in the series.

17. The system of claim 12 , wherein the transmitter is further configured to transmit the second stream of data according to a protocol that expects a receiver to remain on continuously while receiving the second stream of data.

18. The system of claim 12 , wherein the transmitter is further configured (i) to transmit the series of bursts in accordance with a vestigial side-band modulation format and (ii) to transmit the portions of the second stream in accordance with a vestigial side-band modulation format.

19. The system of claim 12 , wherein the transmitter is further configured (i) to transmit the series of bursts in accordance with the ATSC A/53 Digital Television Standard and (ii) to transmit the portions of the second stream in accordance with the ATSC A/53 Digital Television Standard.

20. A system comprising:

means for receiving a first stream of data and a second stream of data, and for dividing the first stream of data into a series of bursts; and

means for simultaneously transmitting over a continuous-mode transmission system (i) the series of bursts during at least two fixed and periodic burst periods of time, the burst periods of time having a first common length of time determined prior to a first of the burst periods of time, wherein successively transmitted bursts in the series are separated in time so as to allow a receiver to enter and exit a power saving mode between receiving successively transmitted bursts, the power saving mode occurring during fixed and periodic power saving periods of time having a second common length of time determined prior to a first of the at least two burst periods of time, wherein the burst transmissions use a data structure that includes a synchronization segment containing data usable by a receiver to synchronize with the burst transmissions, and (ii) portions of the second stream during a time interval during which at least part of the transmission of the first stream of data occurs, with successively transmitted portions in the second stream separated in time by respective time intervals having lengths that are not configured to allow the receiver to enter and to exit the power saving mode between receiving successively transmitted portions of the second stream.