Electronic Warfare
Also known as: EW
Definition
The military discipline of using the electromagnetic spectrum to degrade, deny, or deceive an adversary's electronic systems, encompassing attack techniques such as jamming and GNSS denial alongside protective measures defending one's own electromagnetic-dependent systems from equivalent action.
Key Points
- Encompasses attack, protection, and support functions across the electromagnetic spectrum, rather than referring to a single specific technique — jamming and GNSS denial are two of several EW disciplines rather than being synonymous with EW itself
- Directly threatens GNSS positioning and timing specifically, since GNSS signals are relatively weak by the time they reach a receiver and correspondingly vulnerable to jamming or spoofing by a sufficiently capable adversary
- A genuinely two-sided discipline — EW protective measures (anti-jam techniques, frequency agility, signal hardening) are developed specifically in response to known or anticipated adversary EW attack capability, rather than existing independently of it
- Increasingly relevant beyond traditional military engagement contexts as commercial and civilian systems — aviation, maritime navigation, critical infrastructure timing — depend on the same GNSS and RF infrastructure that military EW techniques can also affect
- EW capability and countermeasure development is a continuously evolving contest, since a protective measure effective against a known attack technique can itself become a target for the next generation of adversary EW capability
Concept
EW operates across the same electromagnetic spectrum that communications, radar, and navigation systems depend on, meaning any RF-dependent system is potentially both an EW target and, with appropriate hardening, a system that can resist EW attack to some degree. The discipline spans deliberately disrupting adversary systems (jamming a communication link, denying GNSS positioning), gathering intelligence from adversary electromagnetic emissions, and protecting one's own systems against these same categories of attack.
Explainer
The reason GNSS positioning and timing specifically feature so prominently in EW discussion is a matter of signal physics rather than particular strategic emphasis — GNSS signals arrive at a receiver extremely weak after traveling from orbit, making them comparatively easy to overpower with a jamming signal or convincingly imitate with a spoofing signal relative to how difficult the same attack would be against a stronger, closer-range signal source. This vulnerability is precisely why GNSS-dependent systems in contested environments increasingly require anti-jam and anti-spoof protective measures as a standard design consideration rather than an optional hardening feature, since GNSS denial can cascade into positioning, navigation, and timing failures across every downstream system depending on that GNSS signal. For CE government and defense verticals, and increasingly for civilian aviation and maritime operations sharing the same GNSS infrastructure, understanding EW as the umbrella threat category — rather than treating jamming or GNSS denial as isolated, unrelated concerns — is what drives coherent protective design across communications, navigation, and timing systems that would otherwise each need to independently discover and respond to the same underlying spectrum-based threat.
Cite this entry
Electronic Warfare. ConnectedEarth Knowledge Base. https://connectedearth.space/knowledge-base/electronic-warfare/ (updated 13 September 2026).