USS Midway MuseumContinuing Education Program

USN Tactical Data Links

USS Midway MuseumContinuing Education Program

USN Tactical Data Links

John Plunkett, LCDR USN-RetDocent, USS Midway Museum

13 and 16 May 2015

USN Tactical Data Links Presentation • Statement of the Fleet Air Defense Problem• Brief history of the pioneering Naval Tactical Data System

(NTDS)• Link 11/TADIL A (HF/UHF Controlled Net Roll Call Reporting)• Link 14 (UHF Frequency Shift Keying) Pre-NTDS Teletype

Broadcast• Link 4A/TADIL C (UHF Digital Air Control)/ACLS “Needles”/RF

Nav. Alignment on deck• Current Fleet TDLs• Link 16/TADIL J (Current Joint/Coalition Forces UHF Jam-Resistant PPLI/Data/Voice

Nodeless Network w Air Control) • SATCOM Joint Range Extension (JRE) (SATCOM UHF/SHF/EHF Exchange of TADIL J

messages Over the Horizon (OTH)/Beyond Line of Sight (BLOS)• Link 22 NATO Improved Link Eleven (NILE) (HF//UHF/Multi-Freq.)

The Fleet Air Defense Problem• In fleet air defense exercises in the 1950s, as many as a

quarter of all contacts were not tracked. • And of the contacts tracked, as many as a quarter of those

contacts were never assigned an interceptor or handed off to onboard weapons for engagement.

• While each anti-air escort ship would be responsible for its own “slice of the pie” sector, attacking aircraft were often inconsiderate enough to cross from one sector to another.

• Handing off the track from one escort to another in the age of paper plots was time consuming, and without an automated system, the chance of overlooking a handoff was quite high

• Giving the enemy a free shot for almost half of its attacking

force was simply unacceptable. The Solution? NTDS!

USN NTDS Development• NTDS was developed circa 1960 using new digital computing

technology and transistor circuit boards. Many technological hurdles overcome.

• OPEVAL in 1962 on USS Oriskany, USS King and USS Mahan• NTDS judged by OPEVAL to be highly reliable (MTBF 1,500 hrs

vice goal of 200 hrs.) (of 26,670 printed circuit cards in 7 computers on 3 ships, just 25 cards failed over eight months) H/W was a winner but S/W was a problem then and now!

• CNO approved NTDS In March 1963 for full service use, and designated NTDS as standard Navy equipment.

• One of the principal goals of NTDS was to create a single tactical situation picture available to all participating units; and the vehicle by which this was done was Tactical Data Links!

USN CIC Pre-Tactical Data Links

USN CIC TDL Console Circa 1980

http://ethw.org/File:Data_Elements_2_.jpeg

USN Link 11 and 4A Data Links

• Radio• Two types of radios are used in Link-11• 2-30 MHz in the HF band

- amplitude modulation

• 225-400 MHz in the UHF band- frequency modulation

• Antenna Coupler• Matches radio output with antenna

impedance

Link-11/TDL ‘A’ Equipment

Combat Systems Computer

(CSC)

CommandAnd

ControlProcessor

(C2P)

Crypto

DataTerminal

Set(DTS)

Radio Coupler

Antenna

Link-11 Equipment

Purpose of Link-11

•Allows Tactical computers to exchange digital information.

Link 4A/TDL ‘C’ Digital Air Control

• Link 4A UHF 300-325 MHZ band. Ships and E-2 Uplink vectors and commands. F-4 and F-14 backlink replies. No longer used for air control as of 2012.

• Automated Carrier Landing System (ACLS) on CVs uses the Link 4A for “Needles” crosshairs Xmit to Acft for landing

• On-Deck Alignment of aircraft INS systems uses Link 4A RF broadcast

• Link 4A was employed by the E-2 Hawkeye to xmit a waypoint of “hostile” ship location to attack acft for War at Sea tactical scenarios in the early 1980s

Rare ACLS Patch for a total “hands-off” Trap

X47B UCAS Mode 1 ACLS

• Tactical Data Link of Choice for the Department of Defense, Joint Services and NATO.

• Provides enhancements to existing data link capabilities.

• Provides data forwarding to/from existing Link 11 data link platforms for a single integrated multi-link architecture

Introduction to Link 16

Link-16 Link-11

Surveillance YES YES

Air Control YES NO

Fighter-to Fighter YES NO

Secure Data YES YES

Extended LOS YES (relay) YES(HF)

Secure Voice YES (2 channels) NO

Jam Resistant YES NO

Positive ID YES LIMITED

Navigation YES NO

Data Forwarding YES NO

Flexible Net YES NO

Link 11/Link 16 Comparisons

Link 16 System Attributes

• Orderly Transition• Connectivity• Range• Relay Capability• Survivability• System Capability• Flexibility• Low error Probability• Jamming Resistance• Information Security

• Low Probability of Intercept• Passive Operations• Relative Navigation• Net Entry• Identification• Message Format Compatibility• Electromagnetic Compatibility• Joint/Combined Force Capability• Multi-netting• Digital Data Formatting

Joint Tactical Information Distribution System (JTIDS) Link 16 Terminal

The Purpose of Link-16 is the exchange of real-time tactical data among units of the force.

Purpose of Link-16

Link-16 satisfies deficiencies found in Legacy data links and supplements them in their operations.

Purpose of Link-16

Link-16 currently uses the following communication components to generate a high capacity, secure, anti-jam waveform:

Joint Tactical Information Distribution System (JTIDS) Multi-functional Information Distribution System (MIDS) MIDS On Ship (MOS) MIDS Joint Tactical Radio System (JTRS) On Ship (MOS

MOD)

JTIDS, MIDS, and MOS utilize the Ultra-High Frequency (UHF) spectrum (Lx Band 960 - 1215

MHz). This limits communications to Line-Of-Sight (LOS) unless suitable relay platforms are employed.

Limitation of Link-16

Joint Range Extension Application Protocol (JREAP) A/B/C Overview

• SATCOM (UHF, SHF, EHF Bands).

• TDL J Messages (Link 16) Exchanged

• Provides BLOS/OTH Coverage

• Enhances Commanders’ War-fighting Capability

• JREAP A (also called Satellite TDL J (STJ)) is half duplex low data rate UHF Band

• JREAP B is full duplex point to point SHF Band

• JREAP C is full duplex TCP-IP based Multicast/Unicast medium data rate EHF Band used extensively for BLOS Comms

NATO Improved Link Eleven (NILE) Link-22 Overview

OBJECTIVES OF THE NILE PROGRAM:

• Design a New Tactical Data Link System (Link 22) Consisting of a Computer to Computer Digital Data Link Among Tactical Data Systems Equipped Ships, Submarines, Aircraft and Shore Sites.

• Link-22 will eventually replace Link-11 and complement Link-16.

• Improve Allied Interoperability

• Enhance Commanders’ War-fighting Capability

NATION IN SERVICE DATE

CANADA 2006

FRANCE 2006

GERMANY 2006

ITALY 2006

NETHERLANDS 2007 Dropped Out

UNITED KINGDOM 2007

UNITED STATES 2007

SPAIN YES Added

Link-22 Overview

Link-22 is an ECM resistant, BLOS tactical data communication system utilizing Fixed Frequency or Frequency Hopping techniques in the HF (3-30 MHz) or the UHF (225-400 MHz) bands.

NU2 NU7NU8

NU3NU4NU6

NU5

NU1

Interrupt Slot

NU3

Link-22 Overview

Key Features• Dynamic TDMA (DTDMA)• Dynamic Congestion Management• COMSEC protected• Interrupt Slot available for injection of High Priority

Messages• Multi-Media/Multi-Network• Routing and Relay • Late Network Entry• Dynamic Reconfiguration/Initialization

Link-22 Overview

TDL Recap• Fleet Air Defense Problem using Radar without displays and

Data Links• Advent of the pioneering Naval Tactical Data System (NTDS)• Link 11/TADIL A C2 to C2 Tactical Data Exchange• Link 14 (UHF Frequency Shift Keying) Teletype Broadcast• Link 4A/TADIL C (UHF Digital Air Control)/ACLS “Needles”/RF

Nav. Alignment on deck• Current Fleet TDLs• Link 16/TADIL J (Current Joint/Coalition Forces UHF Jam-Resistant Primary TDL• SATCOM Joint Range Extension (JRE) (SATCOM UHF/SHF/EHF Exchange of TADIL J

messages OTH Key for Aegis Ballistic Missile Defense (BMD)• Link 22 NATO Improved Link Eleven (NILE) OTH without Satellites for allied nations

Questions?