C4I: Spreading the message far and wide | ADM Nov 09
Tom Muir | Canberra
In Australia, the introduction of tactical data links to suit the current and future information exchange needs of platforms in the maritime, aerospace and land domains has been performed under the watchful eyes of the Tactical Information Exchange Integration Office (TIE IO).
And if the pace of take-up can best be described as measured, there are good reasons for this.
The TIE IO, which is hidden away in Canberra's light industrial area of Fyshwick, is responsible for monitoring and enforcing conformance with the Chief Information Officer's (CIO) Tactical Information Exchange (TIE) policies and standards.
Through the ADF Tactical Data Link Authority (ADFTA) the office provides the point of contact for both technical and procedural Tactical Data Link (TDL) expertise, including engineering and policy support; interoperability and interoperability assurance (for implementation); test and compliance; operational support, and training.
The Tactical Information Exchange Domain (TIED)
According to the latest Defence Capability Plan, Joint Project 2089 is intended to deliver tactical data links to legacy platforms and capabilities of the ADF and the infrastructure required to support tactical data exchange at the force level.
It aims to establish a coherent and coordinated environment for tactical information exchange through a system-of-systems data network.
The scope of the project is to:
• define the standards for the ADF to ensure Joint and Combined Interoperability;
• deliver the infrastructure to support the ADF TIED; and
• invest in legacy systems to enable them to operate to the required standards within the TIED.
Phase 2B is intended to implement a Variable Message Format (VMF) digital communication system on F/A-18A/B Hornet aircraft to provide greater interoperability with land forces during Close Air Support (CAS) missions.
Phase 3 is intended to implement a VMF TIE solution for the Tiger Armed Reconnaissance Helicopter (ARH) and to further develop the common support infrastructure to support the TIED.
Link-11
The ADF has considerable experience with Link 11 which exchanges digital information among airborne, land-based, and ship-board tactical data systems.
It is the primary means for the exchange of data such as radar tracking information.
Link-11 can be used on HF or UHF frequencies although the US Army uses only HF.
Operation in the UHF line of sight (LOS) band, provides ship-to-ship ranges of 25nm, ship-to-air up to150nm (depending on aircraft height), and air-to-air 300nm plus.
Operating in the ground or skywave band HF coverage is 300nm plus.
While Link-11 lacks the robustness and data exchange capabilities of more modern systems such as Link-16, it does provide a necessary ‘beyond line of sight' (BLOS) capability.
In the maritime domain, RAN vessels equipped with, or to be equipped with Link-11 include the Collins submarines, the LPAs, the LHD and AWD, the FFGs, the MHCs and the ANZAC.
The ADF's Northern, Eastern and Mobile Regional Operations Centres are also equipped with Link 11.
Aircraft fitted with Link-11 include AP-3C and AEWC Wedgetail.
The ADF intends operating Link-11 until at least 2015 when the US Navy also plans to phase out its use.
But before phasing it out the ADF will need to select a replacement that provides a similar BLOS capability.
Alternatives under examination include Link-22 and JREAP (Joint Range Extension Application Protocol) an application protocol that is promising because it allows J series messages to be sent over a variety of communications systems including satellite.
The J series is the US messaging format for Link 16 data links.
Link-16
Link-16 is becoming the ADF's primary tactical data link for command, control, and intelligence, providing critical joint interpretability and situation awareness information.
Link 16 uses TMDA architecture and the J message format standard.
Link-16 broadly follows the information exchange concepts of Link-11 but provides certain technical and operational improvements to existing tactical data link capabilities and provides some data exchange elements, which the other data links lack.
Significant advantages over Link-11 include jam resistance, improved security, greater data rate (throughput), and precise location of participants.
A reduced data terminal size allows installation in fighter and attack aircraft.
Although designed many years ago, it is currently entering a phase of rapid uptake by many platforms in many countries, particularly with the introduction of the Multifunctional Information Distribution System (MIDS) terminal.
MIDS supports key theatre functions such as surveillance, identification, air control, and weapons engagement.
This is resulting in moves to enhance its capability, while maintaining compatibility with the existing system.
MIDS is also designed to be fully interoperable with the Joint Tactical Information Distribution System (JTIDS), an earlier Link-16 system.
The primary use of the US Army's MIDS Low Volume Terminal (LVT) is to provide an interoperable joint and allied Link-16 tactical digital data link with air, ground, surface and subsurface platforms.
Link 16 terminals periodically and automatically broadcast a precise position location and identification (PPLI) message, providing a reliable identification of the platform in which the terminal is installed, and reducing or eliminating the risk of damage from friendly fire.
Furthermore, command and control and/or sensor centres can transmit an identification of those sites within their Link 16 track files, providing an indirect method of combat identification.
Link-16 candidates
Australian Link-16 candidate platforms include AEW&C Wedgetail (in progress); F/A-18 Hornet (in progress) and Super Hornet; AAR; CRUs, Upgraded FFG (completed); ANZAC (in progress); AWD and LHD.
Australia has experienced difficulties in introducing Link-16 into service on naval and air platforms before it had fully developed expertise in their use, now provided by the Integration Office.
There have been hurdles in establishing the test environments as well as management concepts and processes needed to ensure the integrity of new networks.
And before introducing them into service the prospect of costly further evolutions of the technology must be faced.
The increased use of data links by ground forces also places more demands on Defence systems.
As the Army begins to make greater use of data links, the issue of scalability of the network assumes a higher priority.
In the past, with limited ships and aircraft operating on the same network, this was not a serious issue.
Now however, the army brings hundreds of tactical nodes to the network, all of which may join and depart as operational needs dictate.
Link 16 via Satellite
Link 16 is being developed in a number of ways beyond the basic concept of integrating a MIDS/JTIDS terminal on a platform and using Link 16 as the language of that terminal.
In the UK, the Royal Navy investigated the use of the Link 16 message standard on a satellite bearer to overcome the LOS limitations of MIDS/JTIDS.
The Satellite Tactical Data Link (STDL) is now part of the RN Ship System requirement and is implemented at the same time as MIDS/JTIDS/Link 16.
The US Navy also invested in satellite Link 16 known as Satellite Tactical Data Information Link J (S-TADIL J).
However the solution chosen is not the same as that of the RN, thus the two systems are not compatible.
The USN also use S-TADIL A, carrying Link 11 data via satellite.
A generic format for extended range Link 16 is being developed to use satellites and landline and is known as the Joint Range Extension (JRE).
JRE is intended to provide a means of exchanging J-Series Link 16 messages over media other than MIDS/JTIDS, primarily to achieve Beyond Line-Of-Sight (BLOS) communication.
This becomes important in order to:
• Operate widely dispersed forces,
• Provide the picture to HQ Joint Operations Command,
• Avoid the saturation of MIDS/JTIDS capacity by the utilisation of multiple relay hops,
• Overcome the requirement to necessarily provide dedicated airborne MIDS/JTIDS relays when the tactical situation would not naturally demand their deployment, and
• Provide Link 16 data communication between surface / ground units when no airborne relays are available.
Heavy workload ahead
The Defence organisation, in particular the TIO Integration Office, has a heavy workload over the next few years.
Not only is it faced with the further introduction of Link-16 in the aerospace and maritime domains, but also with the convergence of the following range of tactical information exchange systems in the various domains:
• Maritime: Link-11 to Link-22 or JREAP; Link-16; Combat Net Radio/Variable Message Format (CNR/VMF).
• Aerospace: Link-16; Beyond Line of Sight (BLOS); CNR/VMF.
• Land: CNR/VMF
• ISR: TCDL/CDL.