Patent ID: 7023380

Claim:
A system for tracking the attitude of a rotating projectile, comprising: a transmit system mounted on the projectile, the system including first and second linearly polarized transmit antennas spaced apart by a distance d′ on the projectile and third and fourth transmit antennas spaced apart by a distance d″ on the projectile, first and second transmitters coupled to the first and second transmit antennas for transmitting first and second transmit signals in phase coherency at first and second different frequencies, third and fourth transmitters coupled to the third and fourth transmit antennas for transmitting third and fourth transmit signals in phase coherency at third and fourth different frequencies; a receiver system located on the projectile's launch platform, the receiver system including a linearly polarized receive antenna system and receiver sections for receiving and downconverting said first, second, third and fourth transmit signals to provide first, second, third and fourth receiver signals; and a processor responsive to said first, second, third and fourth receiver signals for calculating a roll angle, a pitch angle and a yaw angle.