SARH

Semi-active radar homing (SARH) is a common type of missile guidance system, perhaps the most common type for longer-range air-to-air and surface-to-air missile systems. The name refers to the fact that the missile itself is only a passive detector of a radar signal—provided by an external source via radar illumination—as it reflects off the target. Semi-active missile systems use bistatic continuous-wave radar.

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