Method for end-to-end transparent transport of data packets within a space telecommunications system using a network of regenerative satellites with ISLs

Patent metadata

Field	Value
Publication number	US-10425880-B2
Application number	US-201715413229-A
Country	US
Kind code	B2
Filing date	Jan 23, 2017
Priority date	Feb 5, 2016
Publication date	Sep 24, 2019
Grant date	Sep 24, 2019

Abstract

An on-board method for the end-to-end transparent transport of data packets is implemented by a telecommunications system comprising a first, sending station, a second, receiving station, a first, sending satellite, connected directly to the first station, and a second, receiving satellite, connected directly to the second station, the first satellite and second satellite being interconnected via a spaceborne network. The transport method comprises steps allowing an end-to-end transparent adaptive control loop for the adaptive control of the modulation and of the coding of the access links between the first station and the first satellite and between the second station and the second satellite to be implemented.

First claim

The invention claimed is:

1. A method for the end-to-end transparent transport of data packets implemented by a satellite telecommunications system, the telecommunications system comprising:
a first, sending station; and
a second, receiving station; and
a first, sending satellite, connected directly to the first station by a first electromagnetic uplink from the first station and by a first electromagnetic downlink from the first satellite; and
a second, receiving satellite, connected directly to the second station by a second electromagnetic uplink from the second station and by a second electromagnetic downlink from the second satellite;
the first, sending satellite and the second, receiving satellite being interconnected via a spaceborne network comprising at least one inter-satellite link;
the transparent transport method comprising a first step wherein:
the first, sending station transmits a first data message, intended for the second, receiving station and fragmented into a single or multiple first data packets, each first packet having a generic structure, or frame, defined by a predetermined standard;

the transparent transport method additionally comprising the steps wherein:
in a second step, the first, sending satellite estimates a first signal-to-noise-plus-interference ratio SNIR1 of the first uplink on the basis of a first received current packet and inserts information representing the first ratio SNIR1 into a first data go-to field, added to the packet, and transparently retransmits said packet and the information contained within the first go-to field to the second satellite; then
in a third step, the second satellite retransmits said first packet and the information contained within the first field to the second, receiving station; then
in a fourth step, the second station estimates a second signal-to-noise-plus-interference ratio SNIR2 of the second downlink on the basis of said first packet retransmitted by the second satellite, then determines a third signal-to-noise-plus-interference ratio SNIR3 of a first complete link from the first station to the second station as being the minimum from the set formed by the first and second ratios SNIR1 and SNIR2, then inserts information representing the third ratio into a first data return field, added to or already included within a second packet of a second message intended for the first station, and transmits said second packet and the information contained within the first return field to the first station via the second satellite, the spaceborne network and the first satellite; then
in a fifth step, the first station determines a first pair of modulation and coding parameters adapted according to the third ratio SNIR3 sent by the second station and transmits the packets of the first message or of other messages intended for the second station according to the first pair of parameters.

2. The transparent transport method according to claim 1 , the first, second and third signal-to-noise-plus-interference ratios SNIR1, SNIR2, SNIR3 are estimated periodically according to a predetermined period expressed in time or in number of packets.

3. The transparent transport method according to claim 1 , wherein, in the fourth step, the second station also inserts information representing the second ratio SNIR2 into the first data return field;
the transport method additionally comprising a sixth step, interposed between the fourth step and the fifth step, in which the second satellite receives and extracts the second and third ratios SNIR2, SNIR3, then adapts the current modulation of the second downlink according to the highest value from the second and third ratios SNIR2, SNIR3 while leaving the current coding unchanged.

4. The transparent transport method according to claim 1 , additionally comprising the steps wherein:
in a seventh step, subsequent to the fourth step, the second, receiving satellite estimates a fourth signal-to-noise-plus-interference ratio SNIR4 of the second uplink on the basis of a second received current packet and inserts information representing the fourth ratio SNIR4 into a second data go-to field, added to the second packet, and transparently retransmits said second packet and the information contained within the second go-to field to the first satellite; then
in an eighth step, the first satellite retransmits said second packet and the information contained within the second go-to field to the first station; then
in a ninth step, the first station estimates a fifth signal-to-noise-plus-interference ratio SNIR5 of the first downlink on the basis of said second packet retransmitted by the first satellite, then determines a sixth signal-to-noise-plus-interference ratio SNIR6 of a second complete link from the second station to the first station as being the minimum from the set formed by the fourth and fifth ratios SNIR4 and SNIR5, then inserts information representing the sixth ratio SNIR6 into a second data return field, added to a first packet of the first message or of another message intended for the second station, and transmits said first packet and the information contained within the second return field to the second station via the first satellite, the spaceborne network and the second satellite; then
in a tenth step, the second station determines a second pair of modulation and coding parameters adapted according to the sixth ratio SNIR6 sent by the first station and transmits the packets of the second message or of other messages intended for the first station.

5. The transparent transport method according to claim 4 , the fourth, fifth and sixth signal-to-noise-plus-interference ratios SNIR4, SNIR5, SNIR6 are estimated periodically according to a predetermined period expressed in time or in number of packets.

6. The transparent transport method according to claim 4 , wherein, in the ninth step, the first station also inserts information representing the fifth ratio SNIR5 into the second data return field;
the transport method additionally comprising an eleventh step, interposed between the ninth step and the tenth step, wherein the first satellite receives and extracts the fifth and sixth ratios SNIR5, SNIR6, then adapts the current modulation of the first downlink according to the highest value from the fifth and sixth ratios SNIR5, SNIR6 while leaving the current coding unchanged.

7. The transparent transport method according to claim 1 , wherein:
the signalling steps, consisting of inserting and extracting the information representing the ratios SNIR1, SNIR2, SNIR3, SNIR4, SNIR5, SNIR6 added to the packets into/from a first field and a second field, are replaced by steps of routing the measurements of SNIR1, SNIR2, SNIR3, SNIR4, SNIR5, SNIR6 and of rerouting said measurements to the appropriate station from among the first station and the second station or to the appropriate satellite chosen from among the sending satellite and the receiving satellite, the routing and rerouting steps being implemented by a central coordination station for coordinating the telecommunications system.

8. The transparent transport method according to claim 1 , wherein the one or more data packets of the first data packet and/or of the second data packet have the structure of a coded or uncoded baseband frame BBFRAME such as defined by the DVB-S2 protocol.

9. The transparent transport method according to claim 8 , wherein the data packets switched on board the satellites are data packets having the structure of a baseband frame BBFRAME coded according to the DVB-S2 protocol and retaining the end-to-end coding structure.

10. A satellite telecommunications system for the end-to-end high-speed transparent transport of data and comprisi

Assignees

• Thales Sa

Inventors

• Baudoin Cédric
• Chuberre Nicolas
• Dervin Mathieu

Classifications

• H04W40/16 Primary

  based on interference · CPC title

• H04B7/18513

  Transmission in a satellite or space-based system · CPC title

• H04B7/18526

  Arrangements for data linking, networking or transporting, or for controlling an end to end session (data switching networks H04L12/00) · CPC title

• H04L1/0015

  characterised by the adaptation strategy · CPC title

• H04B7/18584

  Arrangements for data networking, i.e. for data packet routing, for congestion control (data switching networks H04L12/00) · CPC title