Almost every guided missile consists of the same functional sections, usually in this order from nose to tail:
- Seeker: the sensor in the nose that observes the target — a radar antenna (active or semi-active), IR detector, SAL detector or a combination. Not every missile has one: command-guided and beam-riding missiles are steered from outside.
- Guidance section: the computing core that calculates steering commands from seeker and/or datalink information according to the guidance law (Guidance methods).
- Autopilot: translates the desired course corrections into actual control surface deflections and keeps the missile stable (gyros, accelerometers).
- Warhead: usually blast-fragmentation; penetrating for large targets or bunkers.
- Fuze: determines the moment of detonation. Besides contact fuzes, mainly the proximity fuze: a mini radar or laser that fires at the moment of closest approach — a direct application of CW/Doppler technology (Continuous wave radar).
- Propulsion: rocket motor (boost, possibly boost-sustain) or an air-breathing engine in cruise missiles.
- Control section: control surfaces (canards, tail fins) and/or thrust vectoring that carry out the calculated corrections.
EW relevance
Every section is a potential point of attack: the seeker can be deceived (flares, chaff, DRFM), the datalink jammed, the proximity fuze triggered or suppressed, and the autopilot can be "overtaxed" with a hard manoeuvre at the right moment (the missile has a limited energy budget).