Jamming is the deliberate transmission of electromagnetic energy to make a receiver unusable or to deceive it. For radar there are two fundamentally different families:
| Noise jamming (Noise jamming) | Deceptive jamming (Deceptive jamming) | |
|---|---|---|
| Principle | drowning the echo in noise | offering false, credible echoes |
| Attacks | the SNR / detection (Clutter and noise) | the tracker's gates (Target tracking by radar: the Target Tracking Radar) |
| Power | a lot needed (brute force) | little needed (intelligence) |
| Effect for the operator | visible: sectors "snow up" | invisible: the radar follows a ghost |
| Does it give the jammer away? | yes, loudly — and it becomes a beacon itself (Home-on-jamming) | much less |
We also distinguish jammers by location:
- Self-protection jammer (SPJ): on board the platform being protected — strongest close to its own echo, but it does point the radar precisely at its carrier.
- Stand-off jammer (SOJ): a specialised EW platform that jams whole sectors on behalf of others from outside the threat range.
- Stand-in jammer: a small (often unmanned or expendable) jammer brought deliberately close to the enemy radar — small power, large effects thanks to 1/R².
- Escort jammer: flies along with the strike formation.
The physical basis underlying everything is the jamming equation from Inverse square law: the jamming signal travels one way (1/R²), the echo out and back (1/R⁴). At long range the jammer wins; only within the burn-through range does the real echo become stronger than the jamming again (Overpowering the jamming signal). All jamming tactics revolve around keeping that burn-through window as small as possible.