System and method for terrestrial broadcast of emergency alerts

1. A method for receiving a terrestrial broadcast signal, the signal containing emergency alert information in machine-readable code, the method comprising:

scanning a transport stream associated with the terrestrial broadcast signal;

said transport stream containing one or more transport stream packets;

identifying one or more transport stream packets containing emergency alert information; and

acquiring one or more transport stream packets containing the emergency alert information;

wherein each transport stream packet comprises a packet header followed by packet data;

wherein the packet header comprises one or more fields;

wherein identifying one or more transport stream packets containing emergency alert information comprises identifying a field in the packet header or transport stream, said field being designated as being associated with said emergency alert information; and

wherein the transport stream packets containing emergency alert information are identified by one or more of the following packet identifier, program number or mobile/handheld ensemble number,

wherein each emergency alert information of said emergency alert information is classified in a plurality of levels, and when the emergency alert information is classified above a threshold level, regular programming is interrupted, wherein the threshold level is determined at a user's receiver,

wherein if a channel is viewed on a delayed basis through a video delay buffer, the user's receiver is switched to a live signal during a duration of an alert triggered by the emergency alert information.

2. A method as recited in claim 1 , wherein identifying one or more transport stream packets containing emergency alert information comprises identifying a field in the transport stream, said field being designated as being associated with said emergency alert information.

3. A method as recited in claim 2 , wherein the transport stream packets containing emergency alert information are identified by service type.

4. A method as recited in claim 2 :

wherein the transport stream comprises one or more tables; and wherein identifying a field in the transport stream comprises:

parsing data relating to one of said one or more tables;

identifying said channel having a type specified as containing emergency alert information; and

acquiring an MPEG-2 program within said channel, the MPEG-2 program comprising said emergency alert information.

5. A method as recited in claim 4 :

wherein the table comprises a virtual channel table (VCT); and

wherein identifying said channel comprises identifying a virtual channel having a type specified as containing emergency alert information.

6. A method as recited in claim 2 , further comprising:

responding to the emergency alert information contained in the acquired transport stream packets; and

displaying an emergency alert message corresponding to said emergency alert information.

7. A method as recited in claim 6 , further comprising generating an audio stream corresponding to the emergency alert information.

8. A receiver for receiving a terrestrial broadcast signal, the signal comprising a transport stream containing emergency alert information in machine-readable code, the receiver comprising:

a tuner for tuning to a specific channel upon receipt of a terrestrial broadcast signal;

a demodulator for demodulating the tuned signal; and

a software module configured to parse demodulated transport stream packets in said Transport Stream;

wherein the software module is configured to identify one or transport stream packets containing emergency alert information;

wherein the software module is configured to acquire one or more transport stream packets containing the emergency alert information;

wherein each transport stream packet comprises a packet header followed by packet data;

wherein the packet header comprises one or more fields;

wherein identifying one or more transport stream packets containing emergency alert information comprises identifying a field in the packet header, said field being designated as being associated with said emergency alert information; and

wherein the transport stream packets containing emergency alert information are identified by one or more of the following packet identifier, program number or mobile/handheld ensemble number,

wherein each emergency alert information of said emergency alert information is classified in a plurality of levels, and when the emergency alert information is classified above a threshold level, regular programming is interrupted, wherein the threshold level is determined at a user's receiver,

wherein if the channel is viewed on a delayed basis through a video delay buffer, the user's receiver is switched to a live signal during a duration of an alert triggered by the emergency alert information.

9. A receiver as recited in claim 8 , wherein the software module is configured to identify a field in the transport stream, said field being designated as being associated with said emergency alert information.

10. A receiver as recited in claim 9 :

wherein the transport stream comprises one or more tables; and

wherein the software module is configured to identify a field in the transport stream by:

parsing data relating to one of said one or more tables;

identify said channel having a type specified as containing emergency alert information; and

acquiring an MPEG-2 program within said channel, the MPEG-2 program comprising said emergency alert information.

11. A receiver as recited in claim 10 :

wherein the table comprises a virtual channel table (VCT); and

wherein identifying said channel comprises identifying a virtual channel having a type specified as containing emergency alert information.

12. A receiver as recited in claim 9 , wherein the software module further comprises code for responding to the emergency alert information contained in the acquired transport stream packets.

13. A receiver as recited in claim 12 , wherein the software module further comprises code for generating an audio stream corresponding to the emergency alert information.

14. A method for receiving a terrestrial broadcast signal, the signal containing emergency alert information in machine-readable code, the method comprising:

scanning a Transport Stream associated with the terrestrial broadcast signal; said Transport Stream containing one or more Transport Stream packets;

wherein the Transport Stream comprises one or more tables;

parsing data relating to one of said one or more tables;

identifying a channel having a type specified as containing emergency alert information; and

acquiring an MPEG-2 program within said channel, the MPEG-2 program comprising said emergency alert information;

wherein the Transport Stream packets containing emergency alert information are identified by one or more of the following packet identifier, program number or mobile/handheld ensemble number,

wherein each emergency alert information of said emergency alert information is classified in a plurality of levels, and when the emergency alert information is classified above a threshold level, regular programming is interrupted, wherein the threshold level is determined at a user's receiver,

wherein if the channel is viewed on a delayed basis through a video delay buffer, the user's receiver is switched to a live signal during a duration of an alert triggered by the emergency alert information.

15. A method as recited in claim 14 :

wherein the table comprises a virtual channel table (VCT); and

wherein identifying said channel comprises identifying a virtual channel having a type specified as containing emergency alert information.

16. A method as recited in claim 15 , wherein the MPEG-2 program is acquired by retrieving an associated TSID and program number.

17. A method as recited in claim 14 , wherein acquiring transport stream packets comprises acquiring IP packets as a standard data channel.

18. A method as recited in claim 1 , wherein acquiring transport stream packets comprises acquiring IP packets as a standard data channel.

19. A receiver as recited in claim 8 , wherein acquiring transport stream packets comprises acquiring IP packets as a standard data channel.

20. A method as recited in claim 14 :

wherein the emergency alert information comprises an EAS announcement that is sent to a service multiplex and IP encapsulator; and

wherein the output of the IP encapsulate is then directed to an M/H framing module to then undergo channel coding.

21. A method as recited in claim 1 :

wherein the emergency alert information comprises an EAS announcement that is sent to a service multiplex and IP encapsulator; and

wherein the output of the IP encapsulate is then directed to an M/H framing module to then undergo channel coding.

22. A receiver as recited in claim 8 :

wherein the emergency alert information comprises an EAS announcement that is sent to a service multiplex and IP encapsulator; and

wherein the output of the IP encapsulate is then directed to an M/H framing module to then undergo channel coding.