- J/S — Jammer-to-Signal Ratio
- The ratio of jammer power to radar signal power at the radar receiver, measured in dB. Determines jamming effectiveness: below 0 dB has no effect, above +20 dB completely denies the radar.
Show the visualisation
- 2D animationTry it: Ew GuideTry it: Multi Domain Spectrum PlannerTry it: Tdl Guide
- J/S Ratio — Jammer-to-Signal Ratio
- The power ratio between an interfering signal and the desired signal at a victim receiver, in dB. A primary metric for electronic warfare effectiveness — typical jamming margin requirements run 6–20 dB depending on the modulation and processing gain.
Show the visualisation
- 2D animationTry it: Ew GuideTry it: Multi Domain Spectrum Planner
- J2 — J2 Perturbation
- The dominant non-spherical-Earth gravity term, caused by Earth's equatorial bulge. Drives nodal regression, apsidal rotation, and is the mechanism behind sun-synchronous and Molniya orbit design. Numerical value: J2 ≈ 1.083 × 10⁻³.
Show the visualisation
- 3D modelTry it: Tdl GuideTry it: Reference Frame VisualizerTry it: Ttps Guide+1 more
- J2 Perturbation
- The dominant gravitational perturbation caused by Earth's equatorial bulge (oblateness). Causes RAAN regression and argument of perigee rotation. Exploited for sun-synchronous orbits.
Show the visualisation
- 3D modelTry it: Reference Frame VisualizerTry it: Smad Orbit VisualizerTry it: Sensor Coverage Mapper
- J2000 — J2000 Reference Epoch
- Standard astronomical epoch: January 1, 2000, 12:00 TT. Defines the ECI reference frame orientation.
Show the visualisation
- J3 — Joint Operations Directorate
- The joint staff directorate responsible for the operations of a joint force.
Show the visualisation
- J4 — Joint Logistics Directorate
- The joint staff directorate responsible for logistics of a joint force.
Show the visualisation
- J5 — Joint Plans Directorate
- The joint staff directorate responsible for long-range and strategic planning of a joint force.
Show the visualisation
- J6 — Joint Communications Directorate
- The joint staff directorate responsible for command, control, communications, and computer systems.
Show the visualisation
- JADC2 — Joint All-Domain Command and Control
- The US concept for connecting sensors and shooters across all domains into a unified decision-making network to accelerate the kill chain and compress the OODA loop.
Show the visualisation
- 3D modelTry it: Tdl GuideTry it: Capability Needs Assessment GuideTry it: Defense Breakthrough Guide+1 more
- JADO — Joint All-Domain Operations
- Integration of military effects across land, sea, air, space, and cyberspace domains. Requires breaking single-service planning silos and selecting the best capability from any domain for each required effect.
Show the visualisation
- 2D animationTry it: Joint Ops Guide
- Jammer/Jamming
- Deliberate transmission of RF energy to disrupt or deny communications or radar operation. Types include noise jamming, deceptive jamming, and spot/barrage jamming.
Show the visualisation
- 2D animation
- JASSM — Joint Air-to-Surface Standoff Missile
- AGM-158 family of subsonic, stealthy cruise missiles launched from tactical and strategic aircraft. Baseline 370 km; ER variant >900 km; XR variant ~1,900 km. Workhorse deep-strike weapon across USAF / USN / allies.
Show the visualisation
- 3D modelTry it: Defense Fundamentals GuideTry it: Aerospace Defense Industry GuideTry it: Defense Missions Guide+1 more
- Javelin
- FGM-148 man-portable anti-tank missile with IR imaging seeker and fire-and-forget capability. Top-attack flight profile defeats reactive armour. Effective range ~2.5 km.
Show the visualisation
- 3D modelTry it: Defense Fundamentals GuideTry it: Modern Warfare GuideTry it: Defense Breakthrough Guide+1 more
- JAXA — Japan Aerospace Exploration Agency
- Japan's national space agency. Notable programmes include Hayabusa asteroid sample return and H-series launch vehicles.
Show the visualisation
- DiagramTry it: Aerospace Defense Industry GuideTry it: Space Standards GuideTry it: Space Fundamentals Guide+1 more
- JBC-P — Joint Battle Command-Platform
- The successor mission-command system providing friendly-force tracking and messaging on tactical platforms.
Show the visualisation
- JCIDS — Joint Capabilities Integration and Development System
- The DoD process for identifying, assessing, and prioritizing joint military capability needs. Produces capability documents (ICD, CDD, CPD) that drive acquisition decisions.
Show the visualisation
- DiagramTry it: Ttps GuideTry it: Military Doctrine Guide
- JCS — Joint Chiefs of Staff
- The body of senior uniformed leaders who advise the President and Secretary of Defense on military matters.
Show the visualisation
- JDAM — Joint Direct Attack Munition
- A GPS/INS guidance kit converting unguided bombs into precision weapons (~10m CEP). Standard USAF/USN munition at ~$25K per kit.
Show the visualisation
- DiagramTry it: Defense Fundamentals GuideTry it: Ttps GuideTry it: Joint Ops Guide+1 more
- JFACC — Joint Force Air Component Commander
- Commander responsible for the air component of a joint force. Typically coordinates air operations through the Air Tasking Order (ATO) cycle.
Show the visualisation
- 2D animationTry it: Orbat GuideTry it: Joint Ops GuideTry it: Ttps Guide+1 more
- JFC — Joint Force Commander
- A general term for the commander of a unified or specified combatant command, subordinate unified command, or joint task force authorized to exercise combatant command or operational control.
Show the visualisation
- DiagramTry it: Orbat GuideTry it: Wargaming Methodology GuideTry it: Ttps Guide+1 more
- JFLCC — Joint Force Land Component Commander
- The commander responsible for planning and directing joint land operations for the JFC.
Show the visualisation
- JFMCC — Joint Force Maritime Component Commander
- The commander responsible for planning and directing joint maritime operations for the JFC.
Show the visualisation
- JFO — Joint Fires Observer
- A trained service member who requests, controls, and adjusts surface fires and provides targeting for close air support.
Show the visualisation
- JFSOCC — Joint Force Special Operations Component Commander
- The commander responsible for planning and directing joint special operations for the JFC.
Show the visualisation
- JIPOE — Joint Intelligence Preparation of the Operational Environment
- Systematic intelligence analysis process that provides the multi-domain threat picture needed for joint planning. Identifies adversary capabilities, vulnerabilities, and probable courses of action.
Show the visualisation
- 2D animationTry it: Wargaming Methodology GuideTry it: Multiint Fusion GuideTry it: Joint Ops Guide+1 more
- JIT — Just-In-Time
- An inventory strategy that delivers materials exactly when needed to minimize on-hand stock.
Show the visualisation
- JOA — Joint Operations Area
- An area of land, sea, and airspace defined by a JFC in which a joint force conducts operations.
Show the visualisation
- JOACC — Joint Operations Area Coordination Center
- A center that coordinates activities and deconflicts operations within a designated joint operations area.
Show the visualisation
- Joint Operations
- Military operations conducted by forces from two or more services of the same nation. Commanded by a Joint Force Commander; doctrine in JP 3-0. Distinguishes from combined operations (multiple nations).
Show the visualisation
- DiagramTry it: Joint Ops GuideTry it: Defense Missions GuideTry it: Cultural Transformation Simulator+1 more
- Joint Ops
- Shorthand for joint operations — the integrated employment of land, maritime, air, space, and cyber capabilities under a single Joint Force Commander. Codified in US JP 3-0 and NATO AJP-3.
Show the visualisation
- DiagramTry it: Cultural Transformation SimulatorTry it: Joint Ops Guide
- JOOD — Junior Officer of the Deck
- The assistant to the officer of the deck who supports watchstanding and ship control.
Show the visualisation
- JOPP — Joint Operation Planning Process
- An orderly, analytical process consisting of logical steps to plan and execute joint operations.
Show the visualisation
- JP — Joint Publication
- A doctrinal publication that provides authoritative guidance for the joint employment of US military forces.
Show the visualisation
- JPSS — Joint Polar Satellite System
- NOAA polar-orbiting weather constellation (Suomi-NPP, NOAA-20, NOAA-21, future J-3 / J-4). Provides global atmospheric soundings, ocean colour, fire detection. ~14 orbits per day at ~830 km SSO.
Show the visualisation
- 3D modelTry it: Space Mission EvolutionTry it: Space Spectrum MapTry it: Day Without Space+1 more
- JREAP — Joint Range Extension Applications Protocol
- A protocol that carries tactical data link messages over long-haul IP or satellite networks.
Show the visualisation
- JSLIST — Joint Service Lightweight Integrated Suit Technology
- The current US military two-piece CBRN protective garment using activated carbon sphere technology. Provides 24 hours of chemical agent protection and 30 days of biological protection. Washable up to 6 times.
Show the visualisation
- DiagramTry it: Defense Fundamentals Guide
- JSON — JavaScript Object Notation
- A plain-text format for structured data, readable by both people and machines. The default way services here exchange records.
Show the visualisation
- JSpOC — Joint Space Operations Center
- The former US center for space surveillance and conjunction assessment, succeeded by the CSpOC.
Show the visualisation
- JSTARS — Joint Surveillance Target Attack Radar System
- An airborne battle management platform that detects and tracks ground moving targets for command and control.
Show the visualisation
- JTAC — Joint Terminal Attack Controller
- Operator who directs close air support from the ground.
Show the visualisation
- JTF — Joint Task Force
- A temporary multi-service military organization established by a combatant commander for a specific mission requiring forces from two or more services. Includes component commands from each contributing service.
Show the visualisation
- DiagramTry it: Orbat GuideTry it: Ttps GuideTry it: Wargaming Methodology Guide+1 more
- JTFC — Joint Task Force Commander
- Commander of a joint force assembled for a specific mission or operation, with authority over all assigned service components.
Show the visualisation
- DiagramTry it: Joint Ops Guide
- JTFHQ — Joint Task Force Headquarters
- The command element that directs and coordinates the operations of a joint task force.
Show the visualisation
- JTIDS — Joint Tactical Information Distribution System
- The communication component of Link 16 providing secure, jam-resistant, high-capacity data and voice communications among military platforms using TDMA on spread-spectrum waveforms with TSEC encryption.
Show the visualisation
- 2D animationTry it: Tdl GuideTry it: Defense Spectrum MapTry it: Waveform Generator+1 more
- JWCC — Joint Warfighting Cloud Capability
- US DoD multi-cloud contract awarded 2022 to AWS, Google, Microsoft, and Oracle — a ceiling of US$9B through 2028 for unclassified through Top Secret workloads. Successor to the cancelled JEDI. Designed to avoid single-vendor lock-in at scale.
Show the visualisation
- Diagram
- JWICS — Joint Worldwide Intelligence Communications System
- The US DoD top-secret/SCI network providing secure voice, video, and data communications for intelligence community and military intelligence users worldwide.
Show the visualisation
- DiagramTry it: Multiint Fusion GuideTry it: Cyber Warfare GuideTry it: Defense Spectrum Map+1 more
Questions this page didn't answer
Send them and we will answer directly, including the ones with awkward answers.
Get in touch