An IADS does not use one radar but a chain of specialised radars, each with its own role in the kill chain (detect → track → engage, SEAD & DEAD). Lower bands see far but coarsely; higher bands see accurately but at shorter range (Radar).
| Role | Typical band | Function | Russian example | See |
|---|---|---|---|---|
| Early Warning | VHF/UHF | very long range; detects early, including counter-stealth | Nebo-M / Nebo-SVU (VHF) | Radar, Electronic Counter Measures |
| Acquisition / surveillance | L/S band | pick up targets and cue the fire-control radar | 91N6 "Big Bird" (S-400) | Radar, Executing the fire control sequence using the EMS |
| Height finding | S/C band | determine height / 3D picture | Protivnik-G / Gamma-DE | Radar |
| Target tracking / fire control | X band | accurate tracking and missile guidance | 92N6 "Grave Stone" (S-400) | Radar, Executing the fire control sequence using the EMS |
| Engagement / illumination | X band | illuminate the target for SARH missiles (Missile Guidance) | 30N6 "Flap Lid" (S-300) | Missile Guidance, SEAD & DEAD |
That an Early Warning radar works in VHF is directly relevant to EW: low frequencies see stealth aircraft better (Electronic Counter Measures), but too coarsely for fire control — hence the handover to X-band radars further down the chain.