Satellite telephony

• US 20050054363A1
• Filed: 09/10/2003
• Published: 03/10/2005
• Est. Priority Date: 09/10/2003
• Status: Active Grant

• Current Assignee: Gilat Satellite Networks Limited
• Original Assignee: Gilat Satellite Networks Limited
• Inventors: Meiri, Tzvika, Beniamini, Gil, Marinov, Izhar
• Granted Patent: US 7,920,502 B2
• Time in Patent Office: Days
• US Class Current: 455/522
• CPC Class Codes: H04B 7/18582 Arrangements for data linking, i.e. for data framing, for error recovery, for multiple access
• CPC Class Codes: H04H 40/90 specially adapted for satellite broadcast receiving
• CPC Class Codes: H04L 2012/6421 Medium of transmission, e.g. fibre, cable, radio, satellite
• CPC Class Codes: H04L 2012/644 Star
• CPC Class Codes: H04L 2012/6481 Speech, voice
• CPC Class Codes: H04L 2012/6483 Video, e.g. MPEG
• CPC Class Codes: H04M 7/1215 where a cable TV network is used as an access to the PSTN/ISDN
• CPC Class Codes: H04N 21/235 Processing of additional data, e.g. scrambling of additional data or processing content descriptors
• CPC Class Codes: H04N 21/23614 Multiplexing of additional data and video streams arrangements for simultaneous broadcast of plural pieces of information H04H20/28
• CPC Class Codes: H04N 21/434 Disassembling of a multiplex stream, e.g. demultiplexing audio and video streams, extraction of additional data from a video stream; Remultiplexing of multiplex streams; Extraction or processing of SI; Disassembling of packetised elementary stream demultiplexing of data packets for data networks, e.g. RTP/UDP H04L65/00
• CPC Class Codes: H04N 21/4348 Demultiplexing of additional data and video streams
• CPC Class Codes: H04N 21/435 Processing of additional data, e.g. decrypting of additional data, reconstructing software from modules extracted from the transport stream
• CPC Class Codes: H04N 21/6143 involving transmission via a satellite
• CPC Class Codes: H04N 21/8106 involving special audio data, e.g. different tracks for different languages

Abstract

Embodiments of the present invention relate generally to packetization techniques for satellite transmission of data, such as telephony data. Some embodiments use the MPEG2 standard in connection with the ETSI DVB data piping profile for arranging the data. Embodiments also relate to method for receiving, demultiplexing and managing incoming telephony data to support a variety of telephony applications including voice, facsimile, Internet and other data.

Claims

1. A method of receiving telephone information, comprising the steps of:

receiving a packet from a satellite at a receiver, said packet having a size of 188 bytes and a header of 4 bytes, said header including a packet identifier;

reviewing said packet identifier to determine whether said received packet contains data of relevance to said receiver;

extracting a first frame of telephone data from said packet, wherein said packet does not contain data belonging to an Internet Protocol packet; and

forwarding said first frame of telephone data to a first telephone device communicatively connected to said receiver.

2. The method of claim 1, further comprising the steps of:

reviewing data contained in said packet to determine whether said packet contains telephone data intended for said receiver;

extracting a second frame of telephone data from said packet; and

forwarding said second frame of telephone data to a second telephone device communicatively connected to said receiver;

3. The method of claim 2, further comprising the steps of:

extracting a third frame of telephone data from said packet; and

forwarding said third frame of telephone data to a third telephone device communicatively connected to said receiver.

4. The method of claim 3, wherein said packet includes at least three VSAT identifiers.

5. The method of claim 2, further comprising the step of reviewing a frame counter contained within said packet to determine a number of frames of telephone data contained in said packet.

6. The method of claim 2, wherein said packet includes a pointer to a location of said second frame, said location being within said packet.

7. The method of claim 1, wherein said packet header includes a payload unit start bit, said step of reviewing data contained in said packet to determine whether said packet contains telephone data further comprising the steps of:

reviewing said header to determine whether said payload unit start bit is set;

if said payload unit start bit is set, reviewing a first byte of a payload portion of said packet to determine whether said first byte points to a location within said payload portion; and

concluding that said packet contains telephone data if said first byte does not point to a location within said payload portion.

8. The method of claim 1, further comprising the step of associating at least one predefined packet identifier with the presence of telephone data, wherein said step of reviewing data contained in said packet to determine whether said packet contains telephone data is based on a comparison of said packet identifier with said at least one predefined packet identifier.

9. The method of claim 1, wherein said packet is encapsulated for transmission via satellite.

10. The method of claim 2, wherein said telephone data consists of voice data.

11. A method of receiving telephone information, comprising the steps of:

receiving an MPEG-2 packet from a satellite at a receiver;

extracting at least three frames of telephone data from said packet; and

forwarding said frames of telephone data to at least one telephone device communicatively connected to said receiver.

12. The method of claim 11, wherein said packet header includes a payload unit start bit that is set, and wherein a first byte in said payload is a pointer that points to a location outside of said payload.

13. The method of claim 11, wherein said packet payload includes three VSAT IDs corresponding to the at least three frames of telephone data contained in said packet payload.

14. The method of claim 11, wherein the telephone data consists of voice data.

15. A satellite receiver system, comprising:

at least one processor; and

at least one computer-readable medium storing executable program code that, when executed by said at least one processor, causes said at least one processor to perform the following steps;

receive, from a satellite, a packet having a size of 188 bytes and a header of 4 bytes, said header including a packet identifier;

review said packet identifier to determine whether said received packet contains data of relevance to said receiver system;

extract a first frame of telephone data from said packet, wherein said packet does not contain data belonging to an Internet Protocol packet; and

forward said first frame of telephone data to a telephone device communicatively connected to said receiver.

16. The system of claim 15, wherein said packet is an MPEG-2 packet and contains at least three frames of telephone data, said frames of telephone data containing compressed voice data.

17. The system of claim 15, further comprising the step of reviewing a payload unit start bit in said header and a telephone code contained in said payload to determine whether said packet contains telephone data.

18. The system of claim 17, wherein said telephone code is the first byte in said payload, and said step of reviewing data contained in said packet to determine whether said packet contains telephone data is based, at least in part, on whether said telephone code is a pointer that points to a location within said payload.

19. A method of receiving telephone information, comprising the steps of:

receiving a series of packets from a satellite at a receiver, said packets each having a size of 188 bytes, a payload of 184 bytes and a first header of 4 bytes, wherein said payload contains a plurality of frames of telephone data and no more than 20 bytes of additional header information for said telephone data;

reviewing information contained in each of said packets to determine whether said payload contains telephone data of relevance to said receiver;

extracting said plurality of frames of telephone data from said payload; and

forwarding said frames of telephone data to at least one device communicatively connected to said receiver.

20. The method of claim 19, wherein at least one of said frames of telephone data is a frame of compressed voice data.

21. The method of claim 20, wherein said payload contains at least three frames of compressed voice data.

22. The method of claim 21, wherein said payload contains at least three VSAT IDs, said VSAT IDs identifying said one or more devices communicatively connected to said receiver.

23. The method of claim 21, wherein said additional header information in said payload contains information identifying a number of frames of compressed voice data contained in said payload.

24. The method of claim 19, further comprising the step of associating a predefined packet identifier with the presence of telephone data;

and wherein said step of reviewing further comprises the steps of;

extracting a packet identifier from said first header; and

determining whether said extracted packet identifier corresponds to said predefined packet identifier.

25. A communication method comprising the steps of:

packing a plurality of frames of telephone data into a payload portion of a single MPEG2 packet according to a DVB data piping profile; and

transmitting said MPEG2 packet to a receiver via an extraterrestrial satellite.

26. The method of claim 25, further comprising the step of determining a number of frames to pack in said MPEG2 packet based on an acceptable delay time.

27. The method of claim 25, further comprising the step of determining a number of frames to pack in said MPEG2 packet based on a size of said frames.

28. The method of claim 25, wherein said payload portion does not contain Internet Protocol data.

29. The method of claim 25, further comprising the step of using a payload unit start bit in a header of said MPEG2 packet to indicate the presence of telephone data in said payload.