Use of signaling for auto-configuration of modulators and repeaters

• US 20050232223A1
• Filed: 04/20/2004
• Published: 10/20/2005
• Est. Priority Date: 04/20/2004
• Status: Active Grant

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Muller, Dominique
• Granted Patent: US 7,626,960 B2
• Time in Patent Office: Days
• US Class Current: 370/350
• CPC Class Codes: H04H 20/02 Arrangements for relaying broadcast information
• CPC Class Codes: H04H 20/72 of terrestrial networks
• CPC Class Codes: H04N 21/2362 Generation or processing of Service Information [SI]
• CPC Class Codes: H04N 21/4345 Extraction or processing of SI, e.g. extracting service information from an MPEG stream
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user

Abstract

The present invention provides methods and apparatuses for configuring a modulator in a digital broadcast system using service information that is also broadcast to wireless terminals. In an embodiment of the invention, the service information is provided by a generator that encapsulates the service information in a transport stream that is received by a cell transmitter. The service information is parsed by each cell transmitter to determine the current modulator parameters. If at least one of the modulation parameters has changed, the associated modulator is reconfigured with the updated modulation parameters. The invention also provides methods and apparatuses for supporting repeaters in the digital broadcast system in order to provide supplementary RF coverage in associated cells. A repeater may retransmit a received radio signal at the same frequency or at a different frequency.

Claims

1. A method for broadcasting a digital service to a wireless terminal in a radio broadcast system, the radio broadcast system comprising a cell, the method comprising:

(A) receiving configuration information from a transport stream, the transport stream supporting the digital service;

(B) synchronously configuring a modulator with modulation parameters contained in the configuration information, the modulator being associated with a cell transmitter; and

(C) transmitting a radio signal through the modulator, the radio signal supporting the digital service.

3. The method of claim 1, wherein the configuration information is included in a network information table (NIT).

4. The method of claim 1, wherein (B) comprises:

(i) if the configuration information corresponds to a cell identification of the cell, parsing the configuration information to obtain an assigned frequency and the modulation parameters; and

(ii) applying the modulation parameters to the modulator.

5. The method of claim 1, wherein (B) comprises:

(i) detecting whether at least one of the modulation parameters changes in value; and

(ii) in response to (i), applying the modulation parameters to the modulator.

6. The method of claim 1, wherein (A) comprises:

(i) separating the configuration information from signaling information.

7. The method of claim 6, wherein at least part of the configuration information is included in a network information table (NIT).

8. The method of claim 1, wherein the modulation parameters are selected from the group consisting of a channel bandwidth, a transmission mode, a code rate, a constellation pattern, and a guard interval.

20. A computer-readable medium having computer-executable instructions for performing the steps recited in claim 1.

22. A computer-readable medium having computer-executable instructions for performing the steps recited in claim 5.

38. The method of claim 1, wherein the radio broadcast system comprises a digital video broadcast system that is selected from the group consisting of a DVB-H system, a DVB-T system, an ATSC system, and an ISDB-T system.

2. The method of claim 2, further comprising:

(D) synchronously generating transmission parameter signaling with transmission parameters contained in the configuration information.

21. A computer-readable medium having computer-executable instructions for performing the steps recited in claim 2.

9. A method for broadcasting a digital service to a wireless terminal in a radio broadcast system, the radio broadcast system comprising a sub-cell, the method comprising:

(A) receiving a radio signal at a first frequency, the radio signal supporting the digital service;

(B) demodulating the radio signal to obtain a demodulated radio signal;

(C) extracting configuration information from the demodulated radio signal;

(D) synchronously applying modulation parameters to a modulator, the modulation parameters being contained in the configuration information; and

(E) retransmitting the radio signal at a second frequency, the configuration information being indicative of the second frequency, the first frequency being different from the second frequency.

10. The method of claim 9, further comprising:

(F) synchronously generating transmission parameter signaling with transmission parameters contained in the configuration information.

11. The method of claim 9, wherein the configuration information is contained in a network information table (NIT).

12. The method of claim 9, wherein (D) comprises:

(i) detecting whether at least one of the modulation parameters changes value; and

(ii) in response to (i), applying the modulation parameters to the modulator.

13. The method of claim 9, further comprising:

(F) configuring the sub-cell with a configured network identification, a configured cell identification, and a configured sub-cell identification, wherein (C) comprises;

(i) matching the configured network identification, the configured cell identification, and the configured sub-cell identification with a received network identification, a received cell identification, and a received sub-cell identification, the received network identification, the received cell identification, and the received sub-cell identification being extracted from the configuration information.

14. The method of claim 9, further comprising:

(F) scanning a radio spectrum; and

(G) determining the first frequency from the radio signal.

15. The method of claim 14, wherein (G) comprises:

(i) matching a configured network identification and a configured cell identification with a received network identification and a received cell identification, wherein the received network identification and the received cell identification are extracted from the configuration information.

16. The method of claim 14, wherein (G) comprises:

(i) receiving a “

next”

network information table (NIT) from the radio signal; and

(ii) extracting the first frequency from the “

next”

NIT.

23. A computer-readable medium having computer-executable instructions for performing the steps recited in claim 9.

24. A computer-readable medium having computer-executable instructions for performing the steps recited in claim 10.

32. The method of claim 9, further comprising:

(F) receiving a “

next”

NIT that is conveyed in the radio signal;

(G) extracting updated configuration information from the “

next”

NIT; and

(H) retuning to an updated frequency, the updated frequency being contained in the updated configuration information.

33. The method of claim 32, further comprising:

(I) in response to (H), if unable to subsequently receive the radio signal at the updated frequency, scanning an assigned frequency spectrum to find the radio signal.

34. The method of claim 9, further comprising:

(F) if unable to receive a “

next”

NIT, scanning an assigned frequency spectrum to find the radio signal.

39. The method of claim 9, wherein the radio broadcast system comprises a digital video broadcast system that is selected from the group consisting of a DVB-H system, a DVB-T system, an ATSC system, and an ISDB-T system.

17. A method for broadcasting a digital service for a wireless terminal in a radio broadcast system, the radio broadcast system comprising a sub-cell, the method comprising:

(A) receiving a radio signal at a selected frequency, the radio signal supporting the digital service;

(B) decoding transmission parameter signaling, the transmission parameter signaling being conveyed in the radio signal;

(C) extracting a received network identification and a received cell identification from the transmission parameter signaling;

(D) if the received network identification and a received cell identification match a configured network identification and a configured cell identification, respectively, extracting modulation parameters from the transmission parameter signaling; and

(E) retransmitting the radio signal at the selected frequency by utilizing the modulation parameters.

18. The method of claim 17, further comprising:

(F) scanning a radio spectrum to receive the radio signal at the selected frequency.

19. The method of claim 17, further comprising:

(F) if the configured network identification or the configured cell identification does not match any corresponding information in the transmission parameter signaling, sending an alarm.

25. A computer-readable medium having computer-executable instructions for performing the steps recited in claim 17.

35. The method of claim 17, further comprising:

(F) receiving a “

next”

NIT that is conveyed in the radio signal;

(G) extracting updated configuration information from the “

next”

NIT; and

(H) retuning to an updated frequency, the updated frequency being contained in the updated configuration information.

36. The method of claim 35, further comprising:

(I) in response to (H), if unable to subsequently receive the radio signal at the updated frequency, scanning an assigned frequency spectrum to find the radio signal.

37. The method of claim 17, further comprising:

(F) if unable to receive a “

next”

NIT, scanning an assigned frequency spectrum to find the radio signal.

40. The method of claim 17, wherein the radio broadcast system comprises a digital video broadcast system that is selected from the group consisting of a DVB-H system, a DVB-T system, an ATSC system, and an ISDB-T system.

26. A cell transmitter that broadcasts a digital service to a wireless terminal in a radio broadcast system comprising a cell, the cell transmitter comprising:

a communications interface that receives a plurality of TS packets conveying signaling information and IP services information;

a modulator that modulates a radio signal with the IP services information in accordance with modulation parameters; and

a processor that receives the signaling information, that extracts the configuration information from the signaling information, and that configures the modulator in accordance with the modulation parameters, the processor configured to perform;

(A) receiving the configuration information from a transport stream, the transport stream supporting the digital service;

(B) synchronously configuring the modulator with the modulation parameters contained the configuration information; and

(C) transmitting the radio signal through the modulator.

27. The cell transmitter of claim 26, wherein the processor is configured to perform:

(D) synchronously generating transmission parameter signaling with transmission parameters contained in the configuration information.

28. The cell transmitter of claim 26, wherein the configuration information is included in a network information table (NIT).

29. A repeater for broadcasting a digital service to a wireless terminal in a radio system comprising a sub-cell, the repeater comprising:

a demodulator that receives a radio signal at a first frequency and that demodulates the radio signal to obtain a demodulated radio signal, the radio signal supporting the digital service;

a modulator that is configured with modulation parameters and that retransmits the radio signal at a second frequency;

a processor that receives the demodulated radio signal and that is configured to perform;

(A) extracting configuration information from the demodulated radio signal;

(B) synchronously applying modulation parameters to a modulator, the modulation parameters being contained in the configuration information; and

(C) determining the second frequency, the configuration information being indicative of the second frequency, the second frequency being different from the first frequency.

30. A repeater for broadcasting a digital service to a wireless terminal in a radio system comprising a sub-cell, the repeater comprising:

a decoder that decodes transmission parameter signaling that is conveyed by a radio signal, the radio signal being received at a selected frequency;

a processor that obtains transmission parameters from the decoder and that is configured to perform;

(A) extracting a received network identification and a received cell identification from the transmission parameter signaling; and

(B) if the received network identification and a received cell identification matches a configured network identification and a configured cell identification, respectively, extracting modulation parameters from the transmission parameter signaling; and

a transmitter that retransmits the radio signal at the selected frequency in accordance with the modulation parameters.

31. A method for broadcasting a digital service for a wireless handheld terminal in a digital video broadcast system, the digital video broadcast system comprising a cell, the method comprising:

(A) receiving a network information table from a transport stream, the transport stream comprising IP packets, the transport stream supporting the digital service;

(B) synchronously configuring a modulator with modulation parameters contained the network information table information, the modulator being associated with a cell transmitter, wherein (B) comprises;

(i) if configuration information from the network information table corresponds to a cell identification of the cell, parsing the configuration information to obtain an assigned frequency and the modulation parameters; and

(ii) applying the modulation parameters to the modulator;

(C) transmitting a radio signal through the modulator, the radio signal supporting the digital service; and

(D) synchronously generating transmission parameter signaling on the radio signal with transmission parameters contained in the network information table information.