TADIL-A/Link 11 is a secure
half-duplex
A duplex communication system is a point-to-point system composed of two or more connected parties or devices that can communicate with one another in both directions. Duplex systems are employed in many communications networks, either to allow ...
tactical data link
A tactical data link (TDL) uses a data link standard in order to provide communication via radio waves or cable used by NATO nations. All military C3 systems use standardized TDL to transmit, relay and receive tactical data.
Multi-TDL network ...
used by
NATO
The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two No ...
to exchange digital data. It was originally developed by a joint committee including members from the
Canadian Navy
The Royal Canadian Navy (RCN; french: Marine royale canadienne, ''MRC'') is the naval force of Canada. The RCN is one of three environmental commands within the Canadian Armed Forces. As of 2021, the RCN operates 12 frigates, four attack submar ...
,
US Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of ...
and
Royal Navy
The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against F ...
to pass accurate targeting information between ships. The final standard was signed in
Ottawa
Ottawa (, ; Canadian French: ) is the capital city of Canada. It is located at the confluence of the Ottawa River and the Rideau River in the southern portion of the province of Ontario. Ottawa borders Gatineau, Quebec, and forms the core ...
in November 1957, where the British proposed the name "TIDE" for "Tactical International Data Exchange". It was later made part of the NATO STANAG standardization process.
The system operates on two frequencies, one in the
high frequency
High frequency (HF) is the ITU designation for the range of radio frequency electromagnetic waves (radio waves) between 3 and 30 megahertz (MHz). It is also known as the decameter band or decameter wave as its wavelengths range from one to ten ...
(HF) range for over-the-horizon (OTH) communications, and another in the
ultra high frequency
Ultra high frequency (UHF) is the ITU designation for radio frequency, radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one ten ...
(UHF) range that uses much smaller antennas and is suitable for smaller ships but lacks the OTH performance. The system broadcasts packets of 30 bits length, with 6 bits of
error correction
In information theory and coding theory with applications in computer science and telecommunication, error detection and correction (EDAC) or error control are techniques that enable reliable delivery of digital data over unreliable communica ...
and 24 bits of payload data. The payload is encrypted.
Link 14 was adopted at the same time as a low-end counterpart to Link 11. Link 14 is essentially a digital
teleprinter
A teleprinter (teletypewriter, teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations. Initia ...
system lacking encryption and automation, intended for ships lacking the ability to use Link 11 data in an automated fashion.
The designation "Link 11" is derived from "Link II", the British designation using Roman numerals before NATO standardized on Arabic numerals. "Link I" was the data link used by the
Comprehensive Display System.
Overview
MIL-STD-6011 exchanges digital information among airborne, land-based, and shipboard tactical data systems. It is the primary means to exchange data such as radar tracking information beyond line of sight. TADIL-A can be used on either
high frequency
High frequency (HF) is the ITU designation for the range of radio frequency electromagnetic waves (radio waves) between 3 and 30 megahertz (MHz). It is also known as the decameter band or decameter wave as its wavelengths range from one to ten ...
(HF) or
ultrahigh frequency
Ultra high frequency (UHF) is the ITU designation for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter (o ...
(UHF). However, the
U.S. Army
The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cl ...
uses only HF. Link 11 relies on a single platform to report positional information on sensor detections. This positional information can be amplified with additional data to qualify the identity of the detected track. Link 11 was developed by
Ralph Benjamin
Ralph Benjamin (17 November 1922 – 7 May 2019) was a British scientist and electrical engineer.
Biography
Benjamin was born in Darmstadt, Germany. He attended boarding school in Switzerland from 1937, and was sent to England in 1939 as ...
while with the Admiralty Surface Weapons Establishment (ASWE),
Portsmouth
Portsmouth ( ) is a port and city in the ceremonial county of Hampshire in southern England. The city of Portsmouth has been a unitary authority since 1 April 1997 and is administered by Portsmouth City Council.
Portsmouth is the most dens ...
.
Link 11 will be replaced by
Link 22
Link 22 is a secure digital radio link in the HF and UHF bands, primarily used by military forces as a tactical data link.
History
During the late 1980s, NATO, agreeing on the need to improve the performance of Link 11, produced a mission need ...
.
Link 11 is defined by the United States Department of Defense as MIL-STD-6011.
The NAUTIS (Naval Autonomous Tactical Information System) originally included the Link 11 system as installed in the
Royal New Zealand Navy
The Royal New Zealand Navy (RNZN; mi, Te Taua Moana o Aotearoa, , Sea Warriors of New Zealand) is the maritime arm of the New Zealand Defence Force. The fleet currently consists of nine ships. The Navy had its origins in the Naval Defence Act ...
's s as part of the mid-life upgrades in the 1980s
HMNZS ''Canterbury''; NAUTIS versions were also found on the
Royal Navy
The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against F ...
Hunt-class minesweepers.
Technical Characteristics
Link 11 is a half-duplex, netted link that normally operates by roll call from a Data Net Control Station (DNCS). Link 11 can also operate in the broadcast mode. The roll call mode of operation used in the Link 11 interface requires that each Participating Unit
(PU) respond in turn while all other stations are receiving. A DNCS initiates the roll call by addressing and transmitting an interrogation message to a specific PU that then responds by transmitting its data. The DNCS then interrogates the next PU in the prescribed roll call. Link 11 can be transmitted on High Frequency (HF) and/or Ultra High Frequency (UHF) bands. Data speed can be selected from bit rates of 2250 or 1364 bits per second (bps). Dual sideband diversity operation and Doppler shift correction features improve reliability and accuracy of data exchange. Link 11 operates
on HF (2-30 MHz) and/or UHF (Line Of Sight (LOS)) (225-400 MHz). Some Data Terminal Sets (DTS) provide the option to select either the Conventional Link 11 Waveform (CLEW) or the Single tone Link 11 Waveform (SLEW). SLEW and CLEW are not compatible waveforms. SLEW, among other enhancements, provides increased propagation and a more powerful Error Detection and Correction (EDAC) algorithm. While the option exists to operate in either CLEW or SLEW, all participants in a given Link 11 net must select the same waveform to achieve connectivity between units. Link 11 is defined in Military Standard (MIL STD) 6011, Tactical Data Link (TDL) A/B Message Standard.
Change of terminology
The term ''Tactical Digital Information Link (TADIL)'' was obsolete (per DISA guidance) and is now more commonly seen as ''
Tactical Data Link
A tactical data link (TDL) uses a data link standard in order to provide communication via radio waves or cable used by NATO nations. All military C3 systems use standardized TDL to transmit, relay and receive tactical data.
Multi-TDL network ...
(TDL)''
See also
*
Comprehensive Display System
*
DATAR
DATAR, short for ''Digital Automated Tracking and Resolving'', was a pioneering computerized battlefield information system. DATAR combined the data from all of the sensors in a naval task force into a single "overall view" that was then transmi ...
References
{{Reflist
External links
* Federation of American Scientists article
Tactical Digital Information Links (TADIL)* Signal Identification Guid
Link-11
Military radio systems
Military of the United States standards
NATO standardisation