DVB low bit rate services
View Patent ↗The invention is directed to efficient transfer of low bit rate services in a communication system. A synchronization symbol which has known characteristics may be included as a first symbol of digital broadcast frames. The synchronization symbol, which can be decoded without having to resort to trial and error methods, contains parameters for the rest of the signal. Low bit rate services are allocated to time slots following the pilot symbol used for synchronization allowing for fast access times with maximum power saving capabilities. A user terminal wakes up just before the synchronization symbol and received the data allocated for the low bit rate services. The user terminal may power off for the remaining time slots which are allocated for higher bit services to conserve power.
1. A method comprising:
receiving a data stream at a terminal over a wireless communications channel;
detecting, by the terminal, a synchronization symbol in the data stream, wherein the synchronization symbol is a first symbol of a frame, and wherein the frame comprises a second synchronization symbol;
obtaining, by the terminal, a low bit rate service included in the data stream after receipt of the synchronization symbol in the data stream and by using information carried by the synchronization symbol; and
upon receipt of the low bit rate service, powering down the terminal for a period of time to conserve battery power of the terminal.
2. The method of claim 1 , wherein the data stream further comprises a high bit rate service.
3. The method of claim 1 , wherein a pre-synchronization symbol precedes the synchronization symbol.
4. The method of claim 1 , wherein the low bit rate service comprises a digital broadcast radio service.
5. The method of claim, 1 wherein the terminal comprises a mobile device.
6. The method of claim 1 , wherein the data stream is broadcasted using a digital video broadcasting transmission.
7. The method of claim 1 , wherein the low bit rate service is adjacent to the synchronization symbol in the data stream.
8. An apparatus comprising:
at least one processor; and
at least one memory having stored therein machine executable instructions that
when executed by the at least one processor, cause the apparatus to:
receive a data stream at the apparatus over a wireless communications channel;
detect a synchronization symbol in the data stream, wherein the synchronization symbol is a first symbol of a frame, and wherein the frame comprises a second synchronization symbol;
obtain a low bit rate service included in the data stream after receipt of the synchronization symbol in the data stream and by using information carried by the synchronization symbol; and
upon receipt of the low bit rate service, power down the apparatus for a period of time to conserve battery power of the apparatus.
9. The apparatus of claim 8 , wherein the data stream further comprises a high bit rate service.
10. The apparatus of claim 8 , wherein a pre-synchronization symbol precedes the synchronization symbol.
11. The apparatus of claim 8 , wherein the low bit rate service comprises digital broadcast radio services.
12. The apparatus of claim 8 , wherein the low bit rate service is adjacent to the synchronization symbol in the data stream.
13. An apparatus comprising:
at least one processor; and
at least one memory having stored therein machine executable instructions, that when executed by the at least one processor, cause the apparatus to:
detect a synchronization symbol, wherein the synchronization symbol is a first symbol of a frame, and wherein the frame comprises a second synchronization symbol;
allocate a time slot adjacent to the synchronization symbol; and
map a low bit rate service into the allocated time slot adjacent to the detected synchronization symbol.
14. The apparatus of claim 13 , wherein a pre-synchronization symbol precedes the synchronization symbol.
15. A method comprising:
detecting, by a processor, a synchronization symbol, wherein the synchronization symbol is a first symbol of a frame, and wherein the frame comprises a second synchronization symbol;
allocating, by the processor, a time slot adjacent to the synchronization symbol; and
mapping, by the processor, a low bit rate service into the allocated time slot adjacent to the detected synchronization symbol.
16. The method of claim 15 , wherein a pre-synchronization symbol precedes the detected synchronization symbol.
17. The method of claim 15 , wherein the low bit rate service comprises a digital broadcast radio service.
18. The method of claim 15 , wherein the synchronization symbol comprises an orthogonal frequency division multiplexing symbol.
19. A non-transitory computer-readable medium storing computer-executable instructions that when executed by a processor, cause an apparatus to:
receive a data stream at the apparatus over a wireless communications channel;
detect a synchronization symbol in the data stream, wherein the synchronization symbol is a first symbol of a frame, and wherein the frame comprises a second synchronization symbol;
obtain a low bit rate service included in the data stream after receipt of the synchronization symbol in the data stream and by using information carried by the synchronization symbol; and
upon receipt of the low bit rate service, power down the apparatus for a period of time to conserve battery power of the apparatus.
20. The method of claim 1 , further comprising:
identifying a signal type associated with the information carried by the synchronization symbol.
21. The method of claim 1 , further comprising:
determining a modulation parameter pertaining to a data symbol used for the low bit rate service.
22. The apparatus of claim 8 , the instructions, when executed by the at least one processor, further cause the apparatus to:
identify a time slot adjacent to the synchronization symbol; and
extract the low bit rate service from the time slot adjacent to the detected synchronization symbol.
23. The apparatus of claim 13 , wherein the allocated time slot is included in one or more time slots of the frame.
24. The method of claim 15 , wherein the allocated time slot is included in one or more time slots of the frame.
25. The method of claim 1 , wherein the low bit rate service occupies a first time slot of a plurality of time slots after the synchronization symbol, the first time slot being adjacent to the synchronization symbol in the data stream, and wherein a high bit rate service occupies one or more remaining time slots after the first time slot.
26. The apparatus of claim 8 , wherein the low bit rate service occupies a first time slot of a plurality of time slots after the synchronization symbol, the first time slot being adjacent to the synchronization symbol in the data stream, and wherein a high bit rate service occupies one or more remaining time slots after the first time slot.