METHOD AND SYSTEM FOR SYNCHRONIZED MAPPING OF DATA PACKETS IN AN ATSC DATA STREAM

• US 20100111109A1
• Filed: 05/20/2009
• Published: 05/06/2010
• Est. Priority Date: 11/06/2008
• Status: Active Grant

• Current Assignee: Rohde & Schwarz GmbH & Company KG
• Original Assignee: Rohde & Schwarz GmbH & Company KG
• Inventors: Rusch-Ihwe, Jens, Simon, Michael, Kramer, Michael, Herzog, Norman
• Granted Patent: US 8,774,069 B2
• Time in Patent Office: Days
• US Class Current: 370/474
• CPC Class Codes: H04H 20/57 for mobile receivers
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 27/02 Amplitude-modulated carrier systems, e.g. using on-off keying; Single sideband or vestigial sideband modulation H04L27/32 takes precedence
• CPC Class Codes: H04N 21/2381 Adapting the multiplex stream to a specific network, e.g. an Internet Protocol [IP] network transmission of MPEG streams over ATM H04L12/5601
• CPC Class Codes: H04N 21/6131 involving transmission via a mobile phone network wireless downlink channel access H04W74/006

Abstract

Mapping data packets of a first data stream into data fields of a second data stream at several transmitters is provided by generating a first data stream with first data packets containing data associated with stationary receivers and second data packets containing data associated with mobile receivers in a head-end, where second data packets at the start of a group of consecutively transmitted second data packets contain placeholders into which signaling information is filled. A first data stream is transmitted from the head-end to each transmitter. Each transmitter extracts signaling information from the second data packets indicating in which data slot and in which data sub-frame of a received data frame the second data packet is transferred. Each transmitter inserts synchronization data in a specific data packet in each data slot containing second data packets. The first and second data packets are mapped consecutively into the second data stream.

Claims

1. A method for mapping data packets of a first data stream into data fields of a second data stream at several transmitters, comprising:

generating a first data stream with first data packets containing data associated with stationary receivers and second data packets containing data associated with mobile receivers in a head-end, whereby second data packets at the start of a group of consecutively transmitted second data packets contain placeholders into which signaling information is filled;

transmitting said first data stream from said head-end to each of said transmitters;

extracting, by each transmitter, said signaling information from said second data packets indicating in which data slot and in which data sub-frame of a received data frame said second data packet is transferred;

inserting, by each transmitter, synchronization data in a specific data packet in each data slot containing second data packets; and

mapping said first and second data packets consecutively into said second data stream.

2. The method according to claim 1,

wherein said specific data packet with synchronization data at the start of a received data frame is positioned at the start of an odd-numbered data field in said second data stream.

3. The method according to claim 1,

wherein said specific data packet with synchronization data in a data slot at an even-numbered position in a data frame is mapped to the first data packet of a data field in said second data stream.

4. The method according to claim 1,

wherein said specific data packet with synchronizing data in a data slot at an odd-numbered position in a received data frame is mapped to the 157^th data packet of a data field in said second data stream.

5. The method according to claim 1,

wherein said first data stream comprises ATSC-M/H data frames and said second data stream includes VSB data fields and an ATSC-M/H group including 118 consecutively positioned second data packets in a data slot, the second data packets having data associated with mobile receivers.

6. The method according to claim 1,

wherein before extracting said signaling information from said second data packet identifying, by each transmitter, the first data packets and second data packets based on the corresponding packet identifier.

7. The method according to claim 1,

wherein after extracting said signaling information, decoding said signaling information using a cycle redundancy check information transmitted at the end of said signaling information to determine a correct transmission of said signaling information.

8. The method according to claim 1,

wherein the specific data packet in each data slot in which synchronizing information is inserted is the 38^th data packet of the data slot.

9. The method according to claim 1,

wherein the number of received second data packets of an ATSC-M/H group is checked for completeness using a continuity counter in a header of each second data packet, and

wherein a number of second data packets containing a dummy data packet is inserted in said data slot corresponding to the number of lost second data packets in an ATSC-M/H group of said data slot.

10. The method according to claim 1,

wherein the number of received first data packets of a data slot is checked for completeness, and

wherein a number of first data packets containing dummy data packets is inserted in said data slot corresponding to the number of lost first data packets in said data slot.

11. The method according to any of claim 1,

wherein said signaling information further includes an ATSC system time associated with each transmitter.

12. The method according to claim 1,

wherein said signaling information contains an information for switching each transmitter from a first operation mode in which data for mobile and stationary receivers are transmitted to a second operation mode in which only data for stationary receivers are transmitted.

13. The method according to claim 12,

wherein after receiving a specific number of data frames of the first data stream without any identified second data packets, each transmitter is switched to said second operation mode.

14. The method according to claim 1,

wherein each placeholder with signaling data in the first two received second data packets are rewritten with a pre-selected value after extracting said signaling information.

15. A system for mapping data packets of a first data stream into data fields of a second data stream at several transmitters, comprising:

a head-end operable to generate a first data stream with first data packets containing data associated with stationary receivers and second data packets containing data associated with mobile receivers, whereby second data packets at the start of a group of consecutively transmitted second data packets contain placeholders into which signaling information is filled;

said head-end further operable to transmit said first data stream to each of said transmitters; and

wherein each transmitter is operable to extract said signaling information from said second data packets indicating in which data slot and in which data sub-frame of a received data frame said second data packet is transferred, insert synchronization data in a specific data packet in each data slot containing second data packets, and map said first and second data packets consecutively into said second data stream.

16. The system according to claim 15,

wherein said specific data packet with synchronization data at the start of a received data frame is positioned at the start of an odd-numbered data field in said second data stream.

17. The system according to claim 15,

wherein said specific data packet with synchronization data in a data slot at an even-numbered position in a data frame is mapped to the first data packet of a data field in said second data stream.

18. The system according to claim 15,

wherein said specific data packet with synchronizing data in a data slot at an odd-numbered position in a received data frame is mapped to the 157^th data packet of a data field in said second data stream.

19. The system according to claim 15,

wherein said first data stream comprises ATSC-M/H data frames and said second data stream includes VSB data fields and an ATSC-M/H group including 118 consecutively positioned second data packets in a data slot, the second data packets having data associated with mobile receivers.

20. The system according to claim 15,

wherein before each transmitter extracts said signaling information from said second data packet identifying, the first data packets and second data packets based on the corresponding packet identifier.

21. The system according to claim 15, further comprising:

a decoder operable to decode said signaling information using a cycle redundancy check information transmitted at the end of said signaling information to determine a correct transmission of said signaling information.

22. The system according to claim 15,

wherein the specific data packet in each data slot in which synchronizing information is inserted is the 38^th data packet of the data slot.

23. The system according to claim 15,

wherein the number of received second data packets of an ATSC-M/H group is checked for completeness using a continuity counter in a header of each second data packet, and

wherein a number of second data packets containing a dummy data packet is inserted in said data slot corresponding to the number of lost second data packets in an ATSC-M/H group of said data slot.

24. The system according to claim 15,

wherein the number of received first data packets of a data slot is checked for completeness, and

wherein a number of first data packets containing dummy data packets is inserted in said data slot corresponding to the number of lost first data packets in said data slot.

25. The system according to any of claim 15,

wherein said signaling information further includes an ATSC system time associated with each transmitter.

26. The system according to claim 15,

wherein said signaling information contains an information for switching each transmitter from a first operation mode in which data for mobile and stationary receivers are transmitted to a second operation mode in which only data for stationary receivers are transmitted.

27. The system according to claim 26,

wherein after receiving a specific number of data frames of the first data stream without any identified second data packets, each transmitter is switched to said second operation mode.

28. The system according to claim 15,

wherein each placeholder with signaling data in the first two received second data packets are rewritten with a pre-selected value after extracting said signaling information.

29. A computer-readable medium having stored thereon sequences of instructions, the sequences of instructions including instructions which when executed by a computer system causes the computer system to perform:

generating a first data stream with first data packets containing data associated with stationary receivers and second data packets containing data associated with mobile receivers in a head-end, whereby second data packets at the start of a group of consecutively transmitted second data packets contain placeholders into which signaling information is filled;

transmitting said first data stream from said head-end to a plurality of transmitters;

extracting, by each transmitter, said signaling information from said second data packets indicating in which data slot and in which data sub-frame of a received data frame said second data packet is transferred;

inserting, by each transmitter, synchronization data in a specific data packet in each data slot containing second data packets; and

mapping said first and second data packets consecutively into a second data stream.

30. The computer-readable medium according to claim 29,

wherein said specific data packet with synchronization data at the start of a received data frame is positioned at the start of an odd-numbered data field in said second data stream.

31. The computer-readable medium according to claim 29,

wherein said specific data packet with synchronization data in a data slot at an even-numbered position in a data frame is mapped to the first data packet of a data field in said second data stream.

32. The computer-readable medium according to claim 29,

wherein said specific data packet with synchronizing data in a data slot at an odd-numbered position in a received data frame is mapped to the 157^th data packet of a data field in said second data stream.

33. The computer-readable medium according to claim 29,

wherein said first data stream comprises ATSC-M/H data frames and said second data stream includes VSB data fields and an ATSC-M/H group including 118 consecutively positioned second data packets in a data slot, the second data packets having data associated with mobile receivers.

34. The computer-readable medium according to claim 29,

wherein before extracting said signaling information from said second data packet identifying, by each transmitter, the first data packets and second data packets based on the corresponding packet identifier.

35. The computer-readable medium according to claim 29,

wherein after extracting said signaling information, decoding said signaling information using a cycle redundancy check information transmitted at the end of said signaling information to determine a correct transmission of said signaling information.

36. The computer-readable medium according to claim 29,

wherein the specific data packet in each data slot in which synchronizing information is inserted is the 38^th data packet of the data slot.

37. The computer-readable medium according to claim 29,

wherein the number of received second data packets of an ATSC-M/H group is checked for completeness using a continuity counter in a header of each second data packet, and

wherein a number of second data packets containing a dummy data packet is inserted in said data slot corresponding to the number of lost second data packets in an ATSC-M/H group of said data slot.

38. The computer-readable medium according to claim 29,

wherein the number of received first data packets of a data slot is checked for completeness, and

wherein a number of first data packets containing dummy data packets is inserted in said data slot corresponding to the number of lost first data packets in said data slot.

39. The computer-readable medium according to any of claim 29,

wherein said signaling information further includes an ATSC system time associated with each transmitter.

40. The computer-readable medium according to claim 29,

wherein said signaling information contains an information for switching each transmitter from a first operation mode in which data for mobile and stationary receivers are transmitted to a second operation mode in which only data for stationary receivers are transmitted.

41. The computer-readable medium according to claim 40,

wherein after receiving a specific number of data frames of the first data stream without any identified second data packets, each transmitter is switched to said second operation mode.

42. The computer-readable medium according to claim 29,

wherein each placeholder with signaling data in the first two received second data packets are rewritten with a pre-selected value after extracting said signaling information.

43. A system for generating an inband signal, comprising:

a pre-processor configured to receive a plurality of transport stream packets, replace a plurality of dummy bytes of one or more of the plurality of transport stream packets with signaling data, and transmit the plurality of transport stream packets including the signaling data over a communications link; and

a post-processor in communication with the pre-processor through the communications link, configured to receive the plurality of transport stream packets including the signaling data, decode the signaling data, and identify at least one of a location of a mobile/handheld group, a subframe of the mobile/handheld group, and a slot number of the mobile/handheld group, based on the signaling data.

44. The system of claim 43, wherein the post-processor is further configured to replace the signaling data with original values of the plurality of dummy bytes received by the pre-processor.

45. A method for using a mobile/handheld system to carry signaling information, comprising:

receiving, by a pre-processor, a plurality of transport stream packets;

replacing a plurality of dummy bytes of one or more of the plurality of transport stream packets with signaling data;

transmitting the plurality of transport stream packets including the signaling data over a communications link;

receiving, by a post-processor, the plurality of transport stream packets including the signaling data;

decoding the signaling data; and

identifying at least one of a location of a mobile/handheld group, a subframe of the mobile/handheld group, and a slot number of the mobile/handheld group, based on the signaling data.

46. The method of claim 45, further comprising:

replacing, by the post-processor, the signaling data with original values of the plurality of dummy bytes obtained by the pre-processor.

47. A method for causing a pre-processor to generate an inband signal, comprising:

receiving a plurality of transport stream packets;

replacing a plurality of dummy bytes of one or more of the plurality of transport stream packets with signaling data;

transmitting the plurality of transport stream packets including the signaling data over a communications link to a post-processor configured to receive the plurality of transport stream packets including the signaling data;

decoding the signaling data; and

identifying at least one of a location of a mobile/handheld group, a subframe of the mobile/handheld group, and a slot number of the mobile/handheld group, based on the signaling data.

48. A computer-readable medium having stored thereon sequences of instructions, the sequences of instructions including instructions which when executed by a computer system causes the computer system to perform:

receiving a plurality of transport stream packets;

replacing a plurality of dummy bytes of one or more of the plurality of transport stream packets with signaling data;

transmitting the plurality of transport stream packets including the signaling data over a communications link to a post-processor configured to receive the plurality of transport stream packets including the signaling data;

decoding the signaling data; and

identifying at least one of a location of a mobile/handheld group, a subframe of the mobile/handheld group, and a slot number of the mobile/handheld group, based on the signaling data.

49. A method for causing a post-processor to process an inband signal, comprising:

receiving, from a communications link, a plurality of transport stream packets including signaling data;

decoding the signaling data; and

identifying at least one of a location of a mobile/handheld group, a subframe of the mobile/handheld group, and a slot number of the mobile/handheld group, based on the signaling data,

wherein the plurality of transport stream packets including signaling data is generated by a pre-processor configured to receive a plurality of transport stream packets, replace a plurality of dummy bytes of one or more of the plurality of transport stream packets with the signaling data, and transmit the plurality of transport stream packets including the signaling data onto a communications link.

50. The method of claim 49, further comprising:

replacing the signaling data with original values of the plurality of dummy bytes.

51. A computer-readable medium having stored thereon sequences of instructions, the sequences of instructions including instructions which when executed by a computer system causes the computer system to perform:

receiving, from a communications link, a plurality of transport stream packets including signaling data;

decoding the signaling data; and

identifying at least one of a location of a mobile/handheld group, a subframe of the mobile/handheld group, and a slot number of the mobile/handheld group, based on the signaling data,

wherein the plurality of transport stream packets including signaling data is generated by a pre-processor configured to receive a plurality of transport stream packets, replace a plurality of dummy bytes of one or more of the plurality of transport stream packets with the signaling data, and transmit the plurality of transport stream packets including the signaling data onto a communications link.

52. The computer-readable medium of claim 51, having stored thereon instructions which cause the computer system to perform:

replacing the signaling data with original values of the plurality of dummy bytes obtained by the pre-processor.