Enhanced data link communication over iridium

• US 8,228,911 B2
• Filed: 09/19/2008
• Issued: 07/24/2012
• Est. Priority Date: 09/19/2008
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Cheriyath, Rithesh, Tumulu, SaiGopal, Payasam, SatyaBhaskar
• Primary Examiner(s): Wilson, Robert
• Assistant Examiner(s): Connor, Brian O
• Application Number:
  US12/233,785
• Publication Number:
  US 20100074253A1
• Time in Patent Office: 1,404 Days
• Field of Search: 370/389, 370/235, 370/238, 370/464, 370/476, 370/913, 340/521
• US Class Current: 370/389
• CPC Class Codes: H04B 7/18506 Communications with or from aircraft, i.e. aeronautical mobile service
• CPC Class Codes: H04B 7/18508 with satellite system used as relay, i.e. aeronautical mobile satellite service
• CPC Class Codes: H04B 7/18584 Arrangements for data networking, i.e. for data packet routing, for congestion control data switching networks H04L12/00

Abstract

A method to reduce latency in a data link communication is provided. The method includes compressing a data packet to be uplinked from a ground station to an aircraft communications addressing and reporting system (ACARS) in an aircraft and determining a packet size of the data packet. The aircraft communications addressing and reporting system is configured to receive packets having a packet size less than or equal to a first threshold packet size. An Iridium router based unrestricted digital inter-working connectivity solution data service is implemented to uplink the compressed data packet if the packet size exceeds a second threshold packet size. A short burst data service is implemented to uplink the compressed data packet if the packet size is less than or equal to the second threshold packet size.

Claims

1. A method to reduce latency in a data link communication, the method comprising:

compressing a data packet to be uplinked from a ground station to an aircraft-communications-addressing-and-reporting-system (ACARS) device in an aircraft, the aircraft-communications-addressing-and-reporting-system device configured to receive packets having a packet size less than or equal to a first threshold packet size;

determining a packet size of the compressed data packet;

when the packet size exceeds a second threshold packet size, transmitting the compressed data packet over an uplink via an Iridium-router-based-unrestricted-digital-inter-working-connectivity-solution-data service; and

when the packet size is less than or equal to the second threshold packet size, transmitting the compressed data packet over the uplink via a short-burst-data service.

2. The method of claim 1, further comprising:

receiving the uplinked compressed data packet having a packet size greater than the first threshold packet size at an Iridium satellite transceiver in the aircraft;

decompressing the received data packet;

multi-blocking the decompressed data packet into a plurality of blocks, wherein the packet size of each block is less than or equal to the first threshold packet size; and

sending the plurality of blocks to the aircraft-communications-addressing-and-reporting-system device onboard the aircraft.

3. The method of claim 2, further comprising:

sequentially receiving a local acknowledgement for each of the plurality of blocks at the Iridium satellite transceiver from the aircraft-communications-addressing-and-reporting-system device;

compiling the received local acknowledgements at the Iridium satellite transceiver; and

sending the compiled acknowledgements as a single acknowledgement to the ground station when the local acknowledgements for each of the plurality of blocks are compiled.

4. The method of claim 1, further comprising:

sequentially receiving a plurality of blocks for a data packet to be downlinked at an Iridium satellite transceiver onboard the aircraft from the aircraft-communications-addressing-and-reporting-system device; and

locally acknowledging each block as it is received.

5. The method of claim 4, further comprising:

compiling the plurality of blocks in the data packet until all the blocks are received;

compressing the compiled blocks to form a data packet to be downlinked;

determining a packet size of the compressed data packet to be downlinked;

when the packet size of the data packet to be sent over a downlink is greater than a third threshold packet size, transmitting the compressed data packet over the downlink via the Iridium-router-based-unrestricted-digital-inter-working-connectivity-solution-data service; and

when the packet size of the data packet to be sent over the downlink is less than or equal to the third threshold packet size, transmitting the compressed data packet over the downlink via the short-burst-data service.

6. A system to enhance data link communication, the system comprising:

an aircraft-communications-addressing-and-reporting-system (ACARS) device onboard an aircraft, the aircraft-communications-addressing-and-reporting-system device configured to receive packets having a packet size less than or equal to a first threshold packet size;

an Iridium satellite transceiver onboard the aircraft, the Iridium satellite transceiver communicatively coupled to the aircraft-communications-addressing-and-reporting-system device and configured to transmit via one of an Iridium-router-based-unrestricted-digital-inter-working-connectivity-solution-data service (RUDICS) or a short-burst-data (SBD) service, the transmission being based on a packet size of a received data packet, the Iridium satellite transceiver including a processor to execute software to;

decompress an uplinked data packet; and

if the decompressed uplinked data packet has a packet size greater than the first threshold packet size, multi-block the decompressed uplinked data packet into a plurality of blocks, each block having less than the first threshold packet size, wherein the Iridium satellite transceiver sequentially sends the plurality of blocks to the aircraft-communications-addressing-and-reporting-system device.

7. The system of claim 6, further comprising at least one ground station communicatively coupled to the Iridium satellite transceiver via an Iridium satellite.

8. The system of claim 7, wherein the ground station comprises:

a data link service provider;

a ground station transceiver communicatively coupled to the data link service provider; and

a processor communicatively coupled to the data link service provider.

9. The system of claim 8, wherein the data link service provider comprises a storage medium holding software executable by the processor to compress data packets to be uplinked and decompress data packets to be downlinked, and, when a packet size of a compressed data packet is less than or equal to a second threshold packet size, the processor is configured to transmit the compressed data packet via an uplink via short-burst-data service, and, when the packet size of the compressed data packet is greater than the second threshold size, the processor is configured to transmit the compressed data packet over the uplink via Iridium-router-based-unrestricted-digital-inter-working-connectivity-solution-data service.

10. The system of claim 6, wherein the Iridium satellite transceiver is configured to receive local acknowledgements for each of the plurality of blocks from the aircraft-communications-addressing-and-reporting-system device.

11. The system of claim 10, wherein the processor compiles the acknowledgements by executing software to re-block the local acknowledgements received from the aircraft-communications-addressing-and-reporting-system device to form a single acknowledgement.

12. The system of claim 11, wherein the Iridium satellite transceiver is configured so that, when the packet size of the single acknowledgement is greater than a third threshold packet size, the Iridium satellite transceiver transmits the acknowledgement over the downlink via the Iridium-router-based-unrestricted-digital-inter-working-connectivity-solution-data service to downlink the acknowledgement.

13. The system of claim 12, wherein the Iridium satellite transceiver is configured so that when the packet size of the data packet is less than or equal to the third threshold packet size, the Iridium satellite transceiver transmits the data packet over the downlink via the short-burst-data service.

14. The system of claim 6, the Iridium satellite transceiver comprising:

a storage medium holding software executable by the processor; and

a memory to store thresholds.

15. A method to reduce latency in a data link communication, the method comprising:

determining a packet size of a data packet to be uplinked from a ground station to an aircraft-communications-addressing-and-reporting-system (ACARS) device in an aircraft, the aircraft-communications-addressing-and-reporting-system device configured to receive packets having packet size less than or equal to a first threshold packet size;

when the packet size is less than or equal to a second threshold packet size, transmitting the data packet over an uplink via a short-burst-data service; and

when the packet size is greater than the second threshold packet size, transmitting the data packet over the uplink via an Iridium-router-based-unrestricted-digital-inter-working-connectivity-solution-data service.

16. The method of claim 15, further comprising:

receiving the uplinked data packet having a packet size greater than the first threshold packet size at an Iridium satellite transceiver in the aircraft;

multi-blocking the uplinked data packet into a plurality of blocks, wherein the packet size of each block is less than or equal to the first threshold packet size; and

sending the plurality of blocks to the aircraft-communications-addressing-and-reporting-system device onboard the aircraft.

17. The method of claim 16, further comprising:

sending a local acknowledgement for each uplinked block from the aircraft-communications-addressing-and-reporting-system device onboard the aircraft to the Iridium satellite transceiver;

compiling the received local acknowledgements at the Iridium satellite transceiver; and

sending the compiled acknowledgements as a single acknowledgement to the ground station when an acknowledgement is received at the Iridium satellite transceiver for each of the plurality of blocks.

18. The method of claim 15, further comprising:

sequentially receiving a plurality of blocks for a data packet to be downlinked at an Iridium satellite transceiver onboard the aircraft from the aircraft-communications-addressing-and-reporting-system device; and

locally acknowledging each block as it is received from the aircraft-communications-addressing-and-reporting-system device.

19. The method of claim 18, further comprising:

compiling the plurality of blocks for the data packet to be downlinked;

determining the packet size of the data packet to be downlinked;

when the packet size of the data packet to be sent over a downlink is greater than a third threshold packet size, transmitting the data packet over the downlink via the Iridium-router-based-unrestricted-digital-inter-working-connectivity-solution-data service; and

when the packet size of the data packet to be sent over the downlink is less than or equal to the third threshold packet size, transmitting the data packet over the downlink via the short-burst-data service.

20. The method of claim 15, further comprising:

compressing the data packet to be uplinked from the ground station to the Iridium satellite transceiver;

decompressing the uplinked compressed data packet received at the Iridium satellite transceiver;

compressing a data packet to be downlinked from the Iridium satellite transceiver to the ground station; and

decompressing the downlinked compressed data packet received at the ground station.