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How does semiactive radar guidance work in the Hawk and AIM-7 Sparrow missile systems?
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rocket and missile system
U.S. soldiers firing an FGM-148 Javelin antitank guided missile during training in Grafenwöhr, Ger., 2006.
Semiactive radar guidance is a method where a target is illuminated or designated by energy emitted from a source external to the missile, such as a ground-based radar or a radar on a launch aircraft. A seeker head within the missile is sensitive to this reflected energy and homes in on the target by tracking the signal as it bounces off the target's surface.1
In the case of the U.S. Hawk surface-to-air missile system and the AIM-7 Sparrow air-to-air missile, the process functions as follows:
- Illumination: The launch platform transmits radar emissions toward the target.1
- Reflection: These radar waves reflect off the target aircraft.1
- Homing: The missile's onboard seeker detects the reflected radar energy.1
- Trajectory Calculation: The missile measures the Doppler shift in the reflected emissions to assist in computing the necessary intercept trajectory to strike the target.1
This guidance method is commonly utilized for terminal homing, allowing the missile to maintain accuracy as it closes in on the target.1