Optimisation for Data Transmission

Patent metadata

Field	Value
Publication number	US-2023057895-A1
Application number	US-202117796972-A
Country	US
Kind code	A1
Filing date	Jan 22, 2021
Priority date	Feb 4, 2020
Publication date	Feb 23, 2023
Grant date	—

Abstract

An optimisation method is presented for the transmission of data along any radio frequency link which can be split into distinct transmission blocks, an example being a beam hopping system. By reordering the packets to be transmitted, it is possible to send packets either at, or nearer to, their optimal modulation and encoding configuration. This will allow for a higher bit to symbol conversion for the majority of packets and hence more data bits can be sent for the same number of symbols.

First claim

1 . A method of optimising data for transmission to occur during a dwell time of a beam hopping schedule of a communications system using a predetermined number of symbols, the method comprising:
determining a plurality of data packets to be transmitted at a first transmission rate; determining required modulation and encoding schemes (MODCODs) for bits of the plurality of data packets; assigning bits of the plurality of packets to a respective baseband transmission frame (BBFRAME) of a sequence of a plurality of BBFRAMEs, in accordance with the required MODCODs for the respective bits, such that:
(i) each BBFRAME is associated with the highest common MODCOD robustness of the MODCODs required for each of the bits in the BBFRAME; and
(ii) the robustness of the MODCOD associated with each BBFRAME increases or decreases in accordance with the chronological position in the sequence of the BBFRAMEs; and
determining a sequence of data packets of the plurality of data packets to be arranged within the BBFRAME sequence in accordance with the assignment of the bits to BBFRAMEs, and outputting the sequence of data packets to a buffer for arrangement as a transport stream comprising the sequence of BBFRAMEs, the method further comprising: determining whether a BBFRAME has capacity to accommodate bits of the plurality of data packets; if the BBFRAME has capacity, assigning the bits to the BBFRAME; and if the BBFRAME does not have capacity and the dwell time is not filled, assigning the bits to an adjacent BBFRAME in the sequence of BBFRAMEs.

2 . A method according to claim 1 , further comprising:
determining that it is not possible to accommodate one or more additional bits of the plurality of data packets in the sequence of BBFRAMEs; determining that optimisation of the sequence of BBFRAMEs is possible if an optimisation limit is not exceeded, the optimisation comprising:
identifying further data packets to be transmitted during the dwell time at a second transmission rate higher than the first transmission rate;
adding further BBFRAMEs to the sequence of BBFRAMEs within the dwell time; and
assigning bits of the plurality of data packets and the further data packets to the sequence of BBFRAMEs and further BBFRAMEs, in accordance with the required MODCODs for the bits.

3 . A method according to claim 2 comprising repeating the optimisation until the optimisation limit is reached.

4 . A method according to claim 3 , wherein the optimisation limit is the bit-to-symbol conversion rate limit for the dwell time.

5 . A method according to claim 3 , wherein the optimisation limit is a predetermined number of optimizations, if the bit-to-symbol conversion rate limit for the dwell time is not exceeded.

6 . A method according to claim 1 comprising:
identifying the MODCOD of each BBFRAME;
preparing a transmission stream based on the sequence of data packets to be arranged in the sequence of BBFRAMEs and the MODCOD of each BBFRAME; and
transmitting the transmission stream.

7 . A method according to claim 6 , in which the order of the data packets in a BBFRAME is arbitrary.

8 . A method according to claim 1 , wherein the required MODCOD of each data packet is contained within the data packet.

9 . An apparatus comprising one or more processors, and memory storing computer-executable instructions that, when executed by the one or more processors, causes the method of claim 1 to be performed.

10 . A satellite payload comprising the apparatus of claim 9 .

11 . A computer program which, when executed by a processor, is arranged to cause the method of claim 1 to be performed.

Assignees

• Airbus Defence & Space Ltd

Inventors

• Pickering Yvonne
• Brown Stephen
• Skinner Peter

Classifications

• H04L1/0018

  based on latency requirement · CPC title

• H04B7/18582 Primary

  Arrangements for data linking, i.e. for data framing, for error recovery, for multiple access · CPC title

• H04L1/0003

  by switching between different modulation schemes · CPC title

• H04B7/18515 Primary

  Transmission equipment in satellites or space-based relays · CPC title

• H04W28/06

  Optimizing {the usage of the radio link}, e.g. header compression, information sizing {, discarding information (system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365)} · CPC title