The Electromagnetic Spectrum: The Cross Domain
By Major Garrett K. Hogan, USA AF, CAOC Uedem
‘Electronic Warfare (EW) is military action that exploits electromagnetic (EM) energy to provide situational awareness and achieve offensive and defensive effects. EW, the conduct of Electromagnetic Operations (EMO), is Warfare in the Electromagnetic Environment (EME).’1
This simple yet broad definition from the highest level of NATO effectively covers all domains and a multitude of activities. Due to this broad scope, a deep understanding of EMO is limited to only a small community of EW experts in the NATO Command Structure, and broader military community. As the conflict in Afghanistan wanes, NATO is reminded that not only have technology and capability advanced during that decade-long struggle, but the world has become increasingly smaller due to communications networking and the exploitation of the entire electromagnetic spectrum. Contemporary military operations are executed in an environment complicated by increasingly dense and complex demands on the EME. An environment once the purview of a very small and specially trained group of EW operators is now of utmost importance at the operational and strategic levels. NATO doctrine was therefore rewritten ‘to significantly improve NATO’s understanding and employment of EW capabilities in response to both the growing availability of modern weapon and information systems, and the increasing exploitation of the EME by adversaries’.2
While all warfighting domains are in some way reliant on the EME, the most heavily dependent are the ‘Information Age’ domains of Air, Space and Cyber. This is why airmen require a solid understanding of NATO EW doctrine and its operational relevance. In support of this understanding, this article highlights EW as an important aspect of conducting joint operations in a contested environment.
Electromagnetic Operations in the Electromagnetic Environment
On today’s battlefield there are many operational capabilities which depend on using or exploiting a portion of the Electromagnetic Spectrum (EMS). These capabilities largely exist in separate disciplines. Examples include communications and data links, sensors (imagery, surveillance, reconnaissance, and radar) and many forms of intelligence collection, EW, navigation and navigation warfare (NAVWAR), targeting and weaponry.
NATO has recognized the EME as a manoeuvre space and defines it as, ‘The totality of electromagnetic phenomena existing at a given location.’3 It is a local operational environment which serves to connect all other physical and informational domains. These connections take place simultaneously and use different but potentially overlapping parts of the EME. Put simply, the EME enables activities and effects across all domains.
Potential adversaries operate within the EME as well and may seek to exploit or interfere with Alliance use of it. In addition, non-combatants make use of the EME as an everyday capability, for such purposes as emergency services, personal or business communications, navigation and entertainment.4 The increasingly dense utilization of the EME drives the important requirement to actively avoid undesired conflicts across the domain. This need for deconfliction between friend, adversary, and neutral use is a concern for operation planners at all levels, land, sea, air, and joint.
EW Actions and Measures
It is beyond the scope of this article to define all EW Measures and Actions. Here, it is more important to understand how they interact in the operational and tactical sense to support the delivery of Electronic Warfare to create operational and tactical effects, as is shown in the diagram below. The diagram also provides a basic understanding of the various EW actions and measures.
The Electromagnetic Spectrum (EMS) can be thought of as a warfighting domain similar to the Air, Space, Cyber, Land, and Sea domains, but it is unique in the fact that it will always interact with all other domains. An action taken in the EMS by the Land Component in the Land Domain may have an impact on other components operating in other domains. For example, take into account Counter Improvised Explosive Device efforts in Afghanistan and Iraq. Efforts there by the Land Component to defeat the radio controlled improvised explosive device (RCIED) required an EW Action, Electronic Attack. This operational action was, in turn, applied at the tactical level as Electronic Counter Measures (an EW Measure) in the form of Counter RCIED Electronic Warfare (CREW) systems such as Symphony and Guardian. These systems, while effective at denying the RCIED threat, had cross domain impacts on Air and Space Domain personnel who were attempting to access the same portion of the EMS for communications and intelligence. It was because of this level of interdependency that the EMS extended beyond just simple joint interaction and required a cross domain focus, meaning that all domains must be considered for every EW operation. The next few paragraphs lay out more examples of interdependency for each domain. The diagram below will serve as a reference for those discussions.
In the Air Domain, communication, navigation, survivability and superiority are all dependent on the EME. Modern navigation and all-weather weapons delivery is reliant on satellite navigation (SATNAV), i.e. the Global Positioning System (GPS). Survivability involves EA and ED. Air superiority, targeting and munitions employment are based on the use of Radio frequency and electro-optical systems to find, fix, track, target and engage adversary capabilities. All of these functions require access to the EME. Stripped of the EME, air forces would not operate effectively. The operational situation would worsen if the adversary were to maintain access to the EME.
With regard to communications, airpower is heavily dependent on the EME because the coordination of air activities, the deconfliction of aircraft tracks as well as the transmission of mission essential data or intelligence would be virtually impossible without radio communication or data links. Communications in the air domain are primarily in the 30 MHz–3 GHz portion of the spectrum, which makes them very susceptible to either unintended or deliberate EM Interference (EMI). Examples include, but are not limited to, EM jamming of Early Warning / Acquisition radars and communications jamming. One method of mitigating EMI is the use of frequency hopping or spread spectrum techniques; however, these techniques require extensive input by the operator. One missed or incorrectly executed step in this EPM will deny the use of a frequency as effectively as the EMI you wanted to evade. Another particular vulnerability is the risk of hostile communications interception as well as position tracking combined with the provision of critical information such as system type and purpose.
Modern all-weather navigation and precision guided munitions (PGM) delivery is reliant on GPS. If an aircraft is unaware of its location in space and time, that aircraft is incapable of accomplishing its mission and is most likely a danger to other aircraft in the surrounding airspace. Internal Navigation Systems (INSs) are capable of providing rudimentary navigation information to air crews, but INS drift rates will sooner or later degrade navigation accuracy to a point that precludes any precise employment of weapons. GPS is a low power signal that is easily overcome by jamming and is likely to be denied or degraded in future conflicts. This is a weakness requiring mitigation at all levels of planning.
Aircraft survivability is likely the most significant airpower matter with regard to EME dependency. Modern Anti-Access / Area Denial capabilities present a significant challenge to air operations. Air superiority in these areas requires first attaining EME dominance. In the air domain, this requires Suppression of Enemy Air Defences (SEAD).5 Air operations in denied airspace require friendly forces to deny enemy air defence systems (in particular radars) the information they need to engage friendly forces. The heart of any SEAD package is the EM Jamming platform. EA / ECM typically requires the employment of extremely high energy to jam the applicable radio frequencies. While most modern fighter aircraft have a sort of built-in offensive and defensive ECM capability, a SEAD strike package requires the employment of special purpose aircraft such as the US EA-6B Prowlers or EA-18G Growlers and EC-130H Compass Call. However, the high power these stand-off jammers employ can have unintended second-order consequences across the EME at ranges well outside their intended target area, including the risk of Radio Frequency fratricide.
Due to the boundless nature of the air domain, EMO in the air have a large footprint. Denying the adversary the use of a specific band of the spectrum may also make it impossible for friendly forces to make use of that same band. Therefore all EMO (EW Actions and EW Measures) must be coordinated by the responsible staff not only with regard to forces, time, and space, but also with regard to frequency bands and spectra involved.
Space is a supporting domain. Space assets have become indispensable, providing advanced early warning, surveillance, precision navigation and timing, and over-the-horizon global communication links. When stripped of EME access, space support to theatre operations is heavily degraded.
Downlinks are a critical vulnerability; however, space jamming effects are likely to be local in nature, as the negation of space communication or control in one region does not necessarily mean that it is negated globally. As such, space can continue to provide capabilities despite being rendered ineffective in a region if adequate contingency measures are in place.
While there is no commonly agreed definition, the US Department of Defence defines Cyberspace as ‘a global domain within the information environment consisting of the interdependent networks of information technology infrastructures and resident data, including the Internet, telecommunications networks, computer systems, and embedded processors and controllers.’6
Cyberspace is the only domain that has been physically and virtually created by humans. A single computer, connected to the network, is nothing but an input / output device to access cyberspace. Cyberspace does not exist without access to the EME, being completely dependent on mostly-commercial digital lines of communication. These lines of communication travel through copper wires, fibre optic cables, and microwave and satellite relays, all of which are applications of the EME. Therefore Cyber and Electronic Warfare share more common ground than not.
The definition and explanation above implies an obvious vulnerability of cyberspace assets; it is possible for an adversary to attack the infrastructure of digital communication lines and computer systems by other than kinetic means. In terms of EMO / EA, the application of Direct Energy Weapons (DEW, e.g. lasers or high-power microwaves) could achieve the same effect. On the other hand cyberspace assets are vulnerable to ‘logical’ cyber-attacks which aim not to destroy the system but use the system for the benefit of the attacker.
Richard Clark describes a perfect example of the effective exploitation of airspace and cyberspace interdependency.7 He points out that the September 2007 Israeli strike on a North Korean-sponsored nuclear weapons facility in Syria succeeded using ‘highly observable’ (as opposed to low observable or ‘stealth’) F-15s and F-16s despite a Russian-designed, modern, long range SAM-based air defence system. He postulates that a cyber-attack delivered by an Israeli EA asset allowed Israeli forces to virtually take control of the Syrian Integrated Air Defence System (IADS), so that the Israeli air strike package could breach Syrian airspace without any risk.
Competition for accessing and using the extremely complex EME will increase in the future. Since the EME has no single owner, there is no way to prevent an adversary’s access to it. Any sort of localized control is only possible through sound application of EW. While airmen must pay particular attention to the EME, EW is inherently joint. That is why all commanders and staff involved in NATO operations must consider the EME, recognizing and supporting their EW staff as critical advisors. Dominance in the EME is critical to ‘information dominance’, which is widely seen as central to modern warfare. The Chinese maxim, ‘a superior force that loses information dominance will be beaten, while an inferior one that seizes information dominance will win’8 puts this dependency into sharp focus.
There will always be a weak point in the EME. Every emitter / receiver is a possible point of attack and every exposed junction a critical vulnerability. Every piece of information is vulnerable to spin, denial, and deception. If our conventional capability is our strongly-united and impenetrable front (as demonstrated in recent conflicts), our EME reliance is our undefended flank. Deconfliction, synchronization, prioritization and protection of the EME are therefore keys to the success of NATO operations.
1. NATO Military Committee, ‘MC 0064/10 NATO Electronic Warfare (EW) Policy’, 27 Mar. 2009, par. 6.
2. NATO, ‘Allied Joint Doctrine for Electronic Warfare, AJP 3.6(B)’, Jul. 2012, par. 0104.
3. NATO ‘Glossary of terms and Definitions, AAP-6’, Edition 2014, p. 2-E-2.
4. NATO ‘Allied Joint Doctrine for Electronic Warfare, AJP 3.6 (B)’, par. 0301.
5. NATO Suppression of Enemy Air Defences, MC 0485/1, 26 Feb. 2014, p. 3 – 12.
6. NATO Cooperative Cyber Defence Centre of Excellence, ‘Cyber Definitions Glossary’, available at https://ccdcoe.org/cyber-definitions.html, accessed 20 Aug. 2015.
7. Richard A. Clarke and Robert K. Knake, ‘Cyber War: The next threat to National Security and What to do About it’, (Harper Collins Press, New York, NY, 2010), p. 1 – 8.
8. Ibid, p. 49 – 50.
Major Garrett K. Hogan
is heading the Support Plans Branch, Combat Plans Division, CAOC2 Uedem, Germany. His duties include the planning, direction, tasking, coordination and supervision for, and subsequent execution of, NATO EW, ISR, Air Transport, JPR and AAR. He is responsible for the direct tasking of more than 20 Combined Reporting Centers, and tactical training of all allied military forces in support of NATO peacetime operations and Operation ATLANTIC RESOLVE. Major Hogan is a Weapons Officer and Senior Electronic Warfare Officer with more than 2,500 RC-135V / W flying hours, including 450 hours of instructor / evaluator time and over 1,250 combat hours in Operations IRAQI FREEDOM, NEW DAWN, and ENDURING FREEDOM, and operational deployments in SOUTHCOM, CENTCOM, EUCOM and PACOM.