Over-the-Horizon (OTH) Communications for Missile Integration


Posted on November 21, 2018 | Completed on November 21, 2018 | By: Travis J. Kneen

What small form factor systems exist or are in development to OTH communications in a satellite-denied environment?


The Defense Systems Information Analysis Center (DSIAC) received a technical inquiry requesting research on over-the-horizon communications technologies for use in satellite-denied environments that have a form factor suitable for a missile. DSIAC searched open sources and the Defense Technical Information Center Research and Engineering Gateway for relevant information and articles. DSIAC also contacted subject matter experts from the Cyber Security and Information Systems Information Analysis Center for additional information. The results of DSIAC’s efforts are summarized in this report.


1.0  Introduction

Defense Systems Information Analysis Center (DSIAC) staff completed literature searches using the Defense Technical Information Center (DTIC) Research and Engineering (R&E) Gateway and open sources to find articles and information relevant to the inquiry. DSIAC staff used the search terms “over the horizon,” “satellite-denied environment,” “communications,” and “beyond line of sight (BLOS).” Closed technical inquiries were also utilized, and DSIAC subject matter experts (SMEs) were contacted for relevant information. SMEs from the Cyber Security and Information Systems Information Analysis Center (CSIAC) [1] supplied documents and information for this report. The information gathered was compiled into a TI response report, which was sent to the inquirer.


2.0  OTH Systems

DSIAC and CSIAC researchers compiled a list of potentially relevant OTH communications solutions in satellite-denied environments. This included network arrays, missiles, and other high-frequency (HF) transmitter/receiver technologies.


2.1  Robust BLOS Communications in Satellite-Denied Environments

The Canadian Department of National Defence released a challenge for new approaches to provide robust OTH/beyond-line-of-sight (BLOS) communications in satellite-denied environments, either by enhancing the reliability of HF and/or satellite communications (SATCOM) approaches or by exploring new technologies and techniques. The challenge was opened on 19 February 2018 and closed on 20 April 2018 [2]. The interested suppliers included L Engineering Services and EION Inc. [3].


2.2  HF Over-the-Horizon Robust Communications Enterprise (HFORCE)

Description: HFORCE communicates via the protected HF waveform and is unique in that it is a non-relay solution in the absence of SATCOM, with the potential to provide global coverage.

Status: Exploratory.

Developer: Massachusetts Institute of Technology Lincoln Labs (Lexington, MA) [4].

The High Dynamic Range Multi-Carrier Amplifier proposal details that this technology should be able to transmit and receive the following frequencies: very high frequency, ultra-high frequency, and HFORCE [5].


2.3  BAE Systems Jindalee Operational Radar Network (JORN)

BAE Systems Australia was awarded a $1.2 billion contract to upgrade and support the JORN, which bounces radar waves off the ionosphere. This work will provide important knowledge for the major AIR 2025 JORN Phase 6 upgrade planned to start in 2018. The upgrade to the over-the-horizon radar (OTHR) network is designed to “open” the system’s architecture, enabling the insertion of next generation technologies and extending the operational life of JORN to beyond 2042 [6-8].


2.4  High-Performance Wireless Research and Education Network (HPWREN)

HPWREN’s project objectives include wide-area, wireless, high-performance networking and connecting sensor networks. HPWREN’s network architecture has a high-performance backbone network and high-speed access links [9].


2.5  Talon Tactical Mobile Over-the-Horizon Radar (TACMOR)

Description: TACMOR will support air domain awareness and maritime domain awareness requirements over the Western Pacific region. The project will demonstrate a subscaled OTHR that is one quarter the size of traditional OTHR systems. In fiscal year (FY) 2017, TACMOR designed and fabricated transmit/receive enclosures, fabricated transmit/receive arrays, and integrated system components with partner nations [10].

TACMOR’s FY 2018 plans include the following:

• Conduct critical design reviews, factory tests, and a military utility assessment of the system.

• Install the OTHR system at the site using partner funding.

• Integrate the system with other intelligence, surveillance, and reconnaissance assets.

• Develop system and training documentation.

• Transition the system to the U.S. Air Force and complete the Joint Capability Technology Demonstration.


2.6  RIM-66C Standard Missile-2 (SM-2) Blocks III/IIIA/IIIB [11]

Description: The RIM-66C SM-2 is the Navy’s primary air defense weapon. SM-2 Block III/IIIA/IIIB configurations are all-weather, ship-launched, medium-range, surface-to-air missiles in service with the Navy and 15 allied navies. SM-2 enables forward naval presence, littoral operations, and projecting and sustaining U.S. forces in antiaccess and area-denied environments. SM-2 Block III/IIIA/IIIB missiles are launched from the Mk 41 vertical launching system installed in Aegis cruisers and destroyers. Block III features improve performance against low-altitude threats and optimize the trajectory shaping within the Aegis command guidance system by implementing shaping and fuse altimeter improvements. Block IIIA features a new directional warhead and a moving-target-indicator fuse design for improved performance and lethality against sea-skimming threats. Block IIIB adds an infrared (IR)-guidance mode capability developed in the missile homing improvement program to improve performance in a stressing electronic countermeasure environment. Blocks IIIA/IIIB will be the heart of the SM-2 inventory for the next 20 years. The latest generation of Block IIIB missiles includes a maneuverability upgrade (SM-2 Block IIIB with MU2) to enhance weapon performance against low-altitude, supersonic maneuvering threats.

Status: The Navy established a depot (FY 2013) and rocket motor regrain program (FY 2014) to maintain the inventory out to 2030 and beyond. This will allow the SM-2 inventory to keep pace with the Navy’s 30-year shipbuilding plan, keep infrastructure in place to convert SM-2 Block IIIA missiles to the unique interrupted continuous wave illumination/joint universal weapon link variant for the three Zumwalt (DDG 1000)-class warships, and support projected increases in fleet proficiency firings. In addition, to avoid significant hardware obsolescence impacts, a modification to SM-2 to incorporate SM-6 technology will result in a supportable missile with commonality benefits to the Standard Missile family. This effort will begin in FY 2017 and result in increased SM-2 capability from incorporating this latest technology.

Developer: Raytheon (Tucson, AZ).


2.7  Naval Integrated Fire Control–Counter Air (NIFC–CA) from the Sea (FTS) [11]

Description: The NIFC-CA FTS kill chain provides both an engage on remote (EOR) and OTH air defense capability, taking advantage of the full kinematic range of the Navy’s missiles, manned aircraft, and cruise missiles. NIFC-CA is a non-acquisition category (ACAT) project established to ensure the alignment of the SM-6 missile, Cooperative Engagement Capability, E-2D Advanced Hawkeye, and Aegis Weapon System. The NIFC-CA “System of 51 Systems” project overcomes traditional radar horizon limitations and expands on cooperative engagement capability sensor netting capability to provide an EOR capability to kill targets OTH at greater ranges than conventional organic fire-control systems.

Status: The NIFC-CA project has conducted more than 200 live-tracking events. All seven live-fire tests successfully verified NIFC-CA capability. One of these tests, conducted in June 2014, was the longest Standard Missile engagement in history. The first deployment of initial capability deployed in FY 2015. Three live-fire events were conducted in the fall of 2016—an integration demonstration with F-35 Joint Strike Fighter, an at-sea test event, and a stream raid presentation.


2.8  KSQ-1 Amphibious Assault Direction System (AADS) [11]

Description: The AADS, with the Enhanced Position Location Reporting System, integrates the Navigation Satellite Timing and Ranging global positioning system (GPS) to form a jam/intercept-resistant, friendly, force-tracking, command and control system that supports the surface assault ship-to-shore movement in amphibious operations. It provides the capability to launch, monitor, track, record, and control landing craft air cushion (LCAC), landing craft utility (LCU) vessels, Naval Beach Group/seabasing craft conducting amphibious assaults from up to 100 nautical miles OTH via radio relay group configuration. It integrates with the Marine Corps tactical radio (PRC-117G) and the Global Command and Control System-Maritime during ship-to-objective maneuver operations.

Status: AADS satisfies operational requirements for an OTH amphibious assault command and control system. AADS is installed in 32 amphibious ships, 78 LCACs, 32 LCUs, Assault Craft Units 4 and 5 control towers, and Expeditionary Warfare Training Group (Atlantic and Pacific) Amphibious Boat Control Team Trainer (ABCTT) classrooms. ABCTT upgraded with AADS Simulator to properly train Amphibious Boat Control Team per fielded boat control configurations. The AADS Program Office is executing the AADS modernization plan, which addresses program information technology risk assessment issues, Windows XP to Windows 7 migration, and other upgrades to improve system integrity. The AADS Program Office is also working to provide a coalition common operating picture with Australian and Canadian Forces using the KOK-23 Crypto Key Generator.


2.9  AGM-154 Joint Standoff Weapon (JSOW) [11]

Description: The JSOW is a family of weapons that enables naval aircraft to attack targets at standoff distances using GPS/inertial navigation system for guidance. All JSOW variants share a common body but can be configured for use against area targets, bunker penetration, and ship attack. Defeating emergent, time-critical threats, whether near or over the horizon, require an all-weather weapon capable of penetrating defended sanctuaries and destroying hostile targets while minimizing the danger of collateral damage to friendly and neutral shipping as well as friendly/neutral assets and personnel ashore. The JSOW Unitary (JSOW C) variant adds an imaging IR seeker and autonomous target acquisition to attack point targets with precision accuracy. The JSOW C-1 incorporates new target-tracking algorithms into the seeker for moving targets, giving the joint force commanders an affordable, air-delivered, standoff weapon that is effective against fixed and relocatable land and maritime targets. Used in conjunction with accurate targeting information and antiradiation weapons, JSOW C-1 will provide the capability to defeat enemy air defenses while creating sanctuaries that permit the rapid transition to low-cost, direct-attack ordnance.

Status: AGM-154A reached initial operational capability (IOC) in 1999, and the AGM-154C variant achieved IOC in FY 2005. JSOW C-1 began procurement in FY 2011 and achieved IOC in June 2016. JSOW C-1 was procured through FY 2016.


2.10  MPR5X0-MICA2DOT Sensor

The MICA2DOT wireless measurement system is a quarter-sized sensor that enables wireless communications with data logging in hard-to-reach places [12, 13].


2.11  MICAz Wireless Measurement System

The MICAz wireless system is a 2.4-GHz mote module used for enabling low-power, wireless sensor networks (WSNs) [12, 14, 15].


3.0  Additional Resources

The brochure “Making 5G New Radio (NR) a Commercial Reality” was supplied by CSIAC and highlights advances in 5G technology and mobile-sized form factor radio frequency front-end controllers and millimeter-wave antennae [12, 16].



[1] CSIAC. https://www.csiac.org/, accessed 12 November 2018.

[2] Government of Canada. “Robust ‘Beyond Line of Sight’ (BLOS) Communications in Satellite-Denied Environments.” Innovation, Science and Economic Development Canada, 19 February 2018, https://www.ic.gc.ca/eic/site/101.nsf/eng/ 00015.html, accessed November 2018.

[3] Government of Canada. “List of Interested Suppliers for ROBUST ‘BEYOND LINE OF SIGHT’ (BLOS) COMMUNICATIONS IN SATELLITE-DENIED ENVIRONMENTS (EN578-170003/03).” Public Works and Government Services Canada, https://buyandsell.gc.ca/procurement-data/tender-notice/PW-18-00816651/list-of-interested-suppliers, 19 February 2018.

[4] U.S. Navy. “2018 The SPAWAR List.” Space & Naval Warfare Systems Command (SPAWAR), 17 January 2018, https://www.public.navy.mil/spawar/Documents/List.pdf, accessed November 2018.

[5] Azoum, S. “High Dynamic Range Multi-Carrier Amplifier (HDR MCA).” U.S. Navy SPAWAR, 8 January 2018, https://www.navysbir.com/n18_1/N181-088.htm, accessed November 2018.

[6] Australian Aviation. “BAE Systems Wins $1.2 Billion Over-the-Horizon Radar Update.” http://australianaviation.com.au/ 2018/03/bae-systems-wins-1-2-billion-over-the-horizon-radar-update/, 5 March 2018.

[7] BAE Systems PLC. “JORN.” https://www.baesystems.com/en/feature/seeing-over-the-horizon, accessed 15 November 2018.

[8] U.S. Air Force. “Jindalee Operational Radar Network.” Peterson Air Force Base, https://www.peterson.af.mil/About/Fact-Sheets/Display/Article/1059651/jindalee-operational-radar-network/, 27 January 2017.

[9] University of California, San Diego. “High Performance Wireless Research and Education Network.” http://hpwren.ucsd.edu/Presentations/hpwren-20050330.pdf, 30 March 2005.

[10] U.S. Office of the Secretary of Defense. “PE 0603648D8Z: Joint Capability Technology Demonstration.” https://www.dacis.com/budget/budget_pdf/FY19/RDTE/D/ 0603648D8Z_45.pdf, February 2018.

[11] U.S. Navy. “U.S. Navy Program Guide 2017.” https://www.hsdl.org/?view&did=805203, 2017.

[12] CSIAC. Personal communication with Deputy Director/Managing Editor. November 2018.

[13] Willow Technologies. “MPR5X0-MICA2DOT Series.” https://www.willow.co.uk/mpr5x0-_mica2dot_series.php, accessed 15 November 2018.

[14] MEMSIC Inc. “MICAz Wireless Measurement System.” http://www.memsic.com/userfiles/files/Datasheets/ WSN/micaz_datasheet-t.pdf, accessed 15 November 2018.

[15] Ali, N. A., M. Drieberg, and P. Sebastian. “Deployment of MICAz mote for Wireless Sensor Network Applications.” 2011 IEEE International Conference on Computer Applications and Industrial Electronics (ICCAIE), Penang, Malaysia, pp. 303-308, 2011, 1 March 2012, http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6162150&isnumber=6162084, accessed November 2018.

[16] Qualcomm. “Making 5G NR a Commercial Reality.” https://www.qualcomm.com/ media/documents/files/making-5g-nr-a-commercial-reality.pdf, September 2018.



DSIAC staff completed literature searches of the DTIC R&E Gateway using Boolean strings of the terms over the horizon, satellite denied, communications, missile, form factor, and names of programs found in open sources.  The search was limited to the last 6 years, and the most relevant publications were Distribution A.

Johnson, C., B. Judy, N. Spurr, J. Gulledge, P. Harris, K. Haubold, J. Riner, W. Goh, Y. K. Hoo, D. Z. Lau, K. Y. Lua, C. L. Ng, W. Phua, and Y. S. Poh. “Organic Over-the-Horizon Targeting for the 2025 Surface Fleet.” Naval Postgraduate School, Distribution A, DTIC Accession Number: ADA632418, 1 June 2015.

Keegan, B. P. “UAV Position Optimization for Wireless Communications.” Naval Postgraduate School, Distribution A, DTIC Accession Number: AD1059967, 1 June 2018.

Anderson, B. D., A. Bishop, G. Mao, and C. Yu. “Robust Multi-Agent Sensor Network Systems.” National Information and Communications Technology (ICT), Distribution A, DTIC Accession Number: ADA560933, 8 May 2012.

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