Method of exchanging communications between a satellite and terminals associated therewith

• US 10,305,578 B2
• Filed: 05/13/2015
• Issued: 05/28/2019
• Est. Priority Date: 05/14/2014
• Status: Active Grant

• Current Assignee: SatixFy Israel Ltd.
• Original Assignee: SatixFy Israel Ltd.
• Inventors: Keshet, Arie
• Primary Examiner(s): Masur, Paul H
• Application Number:
  US15/310,886
• Publication Number:
  US 20170093482A1
• Time in Patent Office: 1,476 Days
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/18519 Operations control, administration or maintenance
• CPC Class Codes: H04B 7/18521 Systems of inter linked satellites, i.e. inter satellite service for optical links between satellites H04B10/118
• CPC Class Codes: H04B 7/212 Time-division multiple access [TDMA]
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04W 84/06 Airborne or Satellite Networks space-based or airborne stations H04B7/185
• CPC Class Codes: H04W 88/16 Gateway arrangements

Abstract

A method is provided for enabling communications between one or more satellites and a plurality of terminals wherein the plurality of terminals are divided into M groups of terminals and wherein the method comprising: forwarding a plurality of communication frames in a forward link, wherein said plurality of frames are divided into N sub-frames, and wherein traffic being carried along the forward link by each of the N sub-frames serves one or more groups of terminals associated with a respective satellite, and assigning, by a satellite return link scheduler, a respective capacity of the return link for at least one of the one or more groups of terminals, wherein the assignment takes into account which of the sub-frames is associated with that at least one group of the terminals.

Claims

1. A method for enabling communications between one or more satellites and a plurality of terminals, said method comprising:

forwarding a plurality of communication frames in a forward link to a plurality of terminals, wherein the plurality of terminals are divided into M groups of terminals;

wherein said plurality of communication frames are divided into N sub-frames, and wherein traffic being carried along the forward link by each of the N sub-frames serves one or more groups of terminals associated with a respective satellite, such that each group is served by at least a fraction of a sub-frame capacity of the plurality of communication frames, associated with a forward link time slot; and

assigning, by a satellite return link scheduler, a respective capacity of the return link for at least one group of terminals of the one or more groups of terminals,

wherein the terminals belonging to the at least one group of terminals are configured such that the terminals cannot receive communications while they are transmitting communications; and

wherein the assignment of the respective capacity of the return link to the at least one group is allocated in return link time slots at which the terminals of the at least one group of terminals are not receiving communication of the sub-frames of said forward link which are is associated with said at least one group of the terminals.

2. The method of claim 1, wherein each of the at least one group of terminals is further divided into sub-groups, and a Physical Layer Header (PL-Header) of each of the forward link communication frames specifies at least one of the sub-groups, and wherein each communication frame carries traffic addressed to the at least one sub-group specified in the respective PL-Header.

3. The method of claim 1, wherein each terminal is configured to decode every PL-Header of the forward link communication frames, and wherein the method further comprises a step whereby if the PL-Header carries a an indication of a sub-group that matches the sub-group of terminals to which a respective terminal belongs, said respective terminal will decode the entire communication frame, and if the PL-Header carries an indication of a sub-group that does not match the sub-group of terminals to which a respective terminal belongs, said respective terminal will not decode the respective entire communication frame.

4. The method of claim 3, wherein in a case where the PL-Header carries an indication of a sub-group that does not match the sub-group of terminals to which a respective terminal belongs, said respective terminal is configured to power down its receiver for the duration of the entire communication frame.

5. The method of claim 1, further comprising a step of alerting terminals from among the plurality of terminals which are currently in a stand-by mode, that traffic that is destined to them is currently being queued and is about to be transmitted to them.

6. The method of claim 1, wherein the one or more satellites are configured to communicate with the plurality of terminals belonging to a public network through at least one gateway, and wherein the plurality of terminals and the at least one gateway are configured to execute identical, bit-exact satellite coverage calculation routines, synchronized for traffic routing and beam/satellite selection with minimal signaling.

7. The method of claim 6, wherein each of the plurality of terminals is configured to generate requests for allocation of return link capacity in another beam or a different satellite, thereby when a terminal switches a beam or a satellite, it is able to immediately utilize said allocated capacity over the new (switched-to) beam or at the new satellite.

8. The method of claim 6, wherein the terminal is configured to:

accept initial geolocation information and to carry out a coarse alignment procedure; and

execute a calibration routine that allows fine-aligning of its orientation and tilt based on reception of communications sent by the terminal to the respective satellite.

9. The method of claim 8, wherein the one or more satellites are configured to:

use gateway-referenced mechanism to establish a system-wide Time of Day (ToD) time base; and

to periodically broadcast information that specifies the information that relates to a respective satellite of the one or more satellites.

10. The method of claim 6, wherein adaptive acquisition time is allocated for a period of time required for carrying out an inter-beam switchover and/or inter-satellite switchover.

11. The method of claim 6, wherein the satellite system is a member selected from a group that consists of:

a Geo Stationary system, a LEO system and a MEO system.

12. The method of claim 1, wherein each of the N sub-frames comprises a baseband frame, and wherein all the baseband frames are of fixed length at different modulations and codes.

13. A method for enabling communications between one or more satellites and a plurality of terminals wherein the plurality of terminals are divided into M groups of terminals and wherein said method comprising:

forwarding a plurality of communication frames in a forward link, wherein said plurality of frames are divided into N sub-frames, and wherein traffic being carried along the forward link by each of the N sub-frames serves one or more groups of terminals associated with a respective satellite; and

assigning, by a satellite return link scheduler, a respective capacity of the return link for at least one of the one or more groups of terminals, wherein said assignment takes into account which of the sub-frames is associated with that at least one group of the terminals,

wherein the one or more satellites are configured to communicate with the plurality of terminals belonging to a public network through at least one gateway, and wherein the plurality of terminals and the at least one gateway are configured to execute identical, bit-exact satellite coverage calculation routines, synchronized for traffic routing and beam/satellite selection with minimal signaling.

14. The method of claim 13, wherein each of the plurality of terminals is configured to generate requests for allocation of return link capacity in another beam or a different satellite, thereby when a terminal switches a beam or a satellite, it is able to immediately utilize said allocated capacity over the new (switched-to) beam or at the new satellite.

15. The method of claim 13, wherein the terminal is configured to:

accept initial geolocation information and to carry out a coarse alignment procedure; and

execute a calibration routine that allows fine-aligning of its orientation and tilt based on reception of communications sent by the terminal to the respective satellite.

16. The method of claim 15, wherein the one or more satellites are configured to:

use gateway-referenced mechanism to establish a system-wide Time of Day (ToD) time base; and

to periodically broadcast information that specifies the information that relates to a respective satellite of the one or more satellites.

17. The method of claim 13, wherein adaptive acquisition time is allocated for a period of time required for carrying out an inter-beam switchover and/or inter-satellite switchover.

18. The method of claim 13, wherein the satellite system is a member selected from a group that consists of:

a Geo Stationary system, a LEO system and a MEO system.