- Semiactive missile doppler
An airborne radar illuminates the target. A "semiactive" missile is using the
radar return it sees to guide toward the target. The radar is operating with a
radio frequency of 10 GHz. The missile and aircraft radar are approaching the
target head-on. The aircraft and the target are heading toward each other at
300 m/sec, and the missile is heading toward the target at 900 m/sec.
How do we calculate the Doppler frequency shift of the reflected
wave of the target by the missile?
How do we guide a missile to a target?
The "semiactive" target illumination is only one of four major methods of missile
guidance. These methods are:
- Semiactive - the missile has a radar receiver which it operates as
a bistatic radar, using target illumination provided by the aircraft radar
- Active - the missile contains its own complete radar, and is independent
of any other equipment. Missile radars are typically small and only operate
over the last ten kilometers of the missile attack. Active radar is typically
used only for the terminal engagement.
- Command guided - the missile has a datalink receiver. The aircraft sends
inertial coordinates of the target location to the missile. The missile then
guides itself toward the location to which it is commanded. This is typically
used only in midcourse. The terminal engaement demands a different method,
often an active radar guidance.
- Beam Rider - The missile maneuvers to stay in the aircraft radar beam, which
must remain always pointed toward the target. If the radar beam can stay on the target,
the missile will reach the target. This often requires very large missile maneuvers,
so it is not commonly used in airborne missile guidance.