LINK 16

What is LINK 16?

Link-16 is a high capacity, secure, jam-resistant, nodeless broadcast-type RF data link that uses a Time Division Multiple Access (TDMA) protocol. It provides information distribution, position location, and identification capabilities in an integrated form for tactical military operations. Link-16 utilises the Joint Tactical Information Distribution System (JTIDS) or the Multi-Functional Information Distribution System (MIDS) terminals, and the protocols, conventions, and fixed word message formats defined by STANAG 5516. JTIDS/MIDS operates in the upper ultra high frequency Lx band.

How does LINK 16 work?

Link 16 operates in the UHF frequency band, providing line-of-sight and beyond-line-of-sight connectivity over considerable distances. It employs a TDMA (Time Division Multiple Access) architecture, allowing multiple users to transmit and receive data on the same frequency without interference.

What are the 3 requirements to get into link 16?

• Correct crypto (Key)
• Network Design Load (NDL)
• Time synchronization (NTR)

Which F-16 Variants have LINK 16 implemented?

Check F-16 Variants.

What is a J-Series message?

• It is a template for data exchange that is programmed into the link 16 structure
• Its data fields are populated by transmitting aircraft and interpreted by receiving aircraft

LINK 16 Limitations in Falcon BMS

• Only C2 can provide SURV air track information.
• Secondary fighter air target tracks, Lock lines and AMRAAM shotlines are not currently implemented.
• Ground LINK 16 is not currently implemented.

LINK 16 PPLI vs Surveillance

• Add later

Acronyms

Short form	Full form	Implemented in BMS	Meaning
	Donor	Partially yes	For situational awareness during a mission, pilots may want to monitor aircraft or targets reported by aircraft that aren’t part of their flight or team. These aircraft, known as donors, can be designated during mission planning (via the Data Cartridge), or selection or deselection can be managed in the cockpit through the LINK 16 DNR page on the DED. Note: Secondary fighter air target tracks, Lock lines and AMRAAM shotlines are not currently implemented.
FC	Fighter Channel	Yes	This Channel establishes the subnet on intraflight communications. This subnet is used to share ownship targets within a flight. The pilot would change the Fighter Channel to receive target information from aircraft that are operating on a different fighter-to-fighter subnet (e.g. different donors) or to join another flight. All members of the flight must select the same Fighter Channel; otherwise, the Link 16 target sorting messages from the flight members will not be received. The numerical value can be set between 0 and 126.
IDM	Improved Data Modem	Yes	The F-16's improved data modem is a crucial component of its avionics system, enhancing communication capabilities for both command and control purposes anddata transfer. The IDM facilitates seamless and secure transmission of various typesof data, including mission-critical information, sensor data, and tactical updates between aircrafts. IDM was designed in the late 70’s before LINK 16 was on the horizon of the aircraft manufactures. Even if limited in features compared to MIDS/JTIDS systems, it follows the same principle of exchanging data.
JDN	Joint Data Net	Yes	An interconnected network of JTIDS/MIDS based systems which links air and missile defence Command and Control and weapons systems across L16 capable forces.
JTIDS	Joint Tactical Information Distribution System	Yes	Refers to the communications component of Link-16. It encompasses the Class 2 terminal software, hardware, RF equipments, and the high-capacity, secure, antijam waveform that they generate. Among NATO subscribers, the equivalent term for JTIDS is the Multifunctional Information Distribution System (MIDS).
MC	Mission Channel	Yes	This Channel establishes the subnet on the C2 (e.g. AWACS or ABCCC) aircraft is operating. The control NPG is used by C2 to transmit assignments to the flight lead and for the flight lead to transmit responses and report assignment status. As a flight progresses to the target area, the controlling aircraft could change. When a controller change is required, the current controlling aircraft transmits a request for handover message to the flight indicating the new controllers subnet (i.e., MC). After accepting the handover request, the flight members change the mission channel to communicate with the new controller. The numerical value can be set between 0 and 127.
MIDS	Multifunctional Information Distribution System	Yes	See JTIDS
NDL	Network Design Load	Yes	This system used to initialize the JTIDS/MIDS terminal
NPG	Network Participation Groups	Yes	FC and MC channels are part of dedicated NPG’s. Each channel and its number define what data can be exchanged on that channel. If you create a package for example, all LINK 16 capable aircraft of this package will have the same FC and MC (because one AWACS controller will be responsible for this package).
PPLI	Precise Participant Location and Identification	Yes	PPLI air tracks are shared between aircraft sharing the same NPG. Each PPLI message contains an abundance ofinformation about a unit, including its detailed position andidentification information, its time quality, its IFF codes, and much more.
SC	Special Channel	Yes	This Channel establishes for SEAD NPG and identification information.The numerical value can be set between 0 and 126.
SURV	Surveillance	Yes	This message is used to share air trajectory data and is primarily disseminated by command and control agencies.

LINK 16 Net Message Table (STANAG 5516)

J	Series	Message	Note
J0.0	Network Management	Initial Entry
J0.1		Test Message
J0.2		Net Time Update
J0.3		Time Slot Assignment
J0.4		Radio Relay Control
J0.5		Repromulgation Relay
J0.6		Comm Control
J0.7		TSR Announcement
J1.0		Connectivity Interrogation
J1.1		Connectivity Status
J1.2		Route Establishment
J1.3		Acknowledgment
J1.4		Communication Status
J1.5		Net Control Initialization
J1.6		Needline PG Assignment
J2.0	Precise Participation Location & Identification (PPLI)	Indirect Interface Unit PPLI
J2.2		Air PPLI	Transmitted by Link 16 air participants that provides network participation status, identification, positional information, and relative navigation information. This message can include the voice call sign, position (latitude/longitude), altitude, course, IFF codes, air platform type (generic - fighter, bomber, attack, etc.), air platform activity (engaging, investigating, etc.), etc.
J2.3		Surface (Maritime) PPLI
J2.4		Subsurface (Maritime) PPLI
J2.5		Land (Ground) Point PPLI
J2.6		Land (Ground) Track PPLI
J3.0	Surveillance	Reference Point
J3.1		Emergency Point
J3.2		Air Track	This message is used to exchange information on air tracks. The message is primarily transmitted by a command and control agency. The message includes exercise (exercise messages are filtered out)/nonexercise tracks, track number, strength, position, speed, course, identity (pending, unknown, assumed friend, friend, neutral, suspect, hostile, or undefined), IFF codes, air platform type (generic - fighter, bomber, attack, etc.), air platform activity (engaging, investigating, etc.), air specific type (F-15, F-16, Mig-29, etc.), etc.
J3.3		Surface (Maritime)
J3.4		Subsurface (Maritime) Track
J3.5		Land (Ground) Point/Track
J3.6		Space Track
J3.7		Electronic Warfare Product Information
J5.4	Anti Submarine Warfare	Acoustic Bearing/Range
J6.0	Intelligence	Intelligence Information
J7.0	Track Management	Track Management
J7.1		Data Update Request
J7.2		Correlation
J7.3		Pointer
J7.4		Track Identifier
J7.5		IFF/SIF Management
J7.6		Filter Management
J7.7		Association
J8.0		Unit Designator
J8.1		Mission Correlation Change
J9.0	Weapons Coordination & Management	Command
J9.1		Engagement Coordination
J10.2		ECCM Coordination
J10.3		Handover
J10.5		Controlling Unit Report
J10.6		Pairing
J12.0	Control	Mission Assignment
J12.1		Vector
J12.2		Precision AC Direction
J12.3		Flight Path
J12.4		Controlling Unit Change
J12.5		Target/Track Correlation
J12.6		Target Sorting
J12.7		Target Bearing
J13.0	Platform & System Status	Airfield Status
J13.2		Air Platform Status
J13.3		Surface Platform Status
J13.4		Subsurface Platform Status
J13.5		Land Platform Status
J14.0	Electronic Warfare	EW Parametric
J14.2		EW Coordination & Control
J15.0	Threat Warning	Threat Warning
J16.0		Imagery
J17.0		Weather over target
J28.0	National Use	US National 1-Army
J28.1		US National 2-Navy
J28.2		US National 3-USAF
J28.3		US National 4-USMC
J28.4		FR National 1
J28.5		FR National 2
J28.6		US National 5-NSA
J28.7		UK National 1
J31.0	Miscellaneous	OTAR Management
J31.1		OTAR
J31.7		No Statement
RTT-A	Round Trip Timing	RTT Addressed
RTT-B		RTT Broadcast
RTT-REP		RTT Reply