Patent attributes
A method is presented by which a missile body roll angle relative to earth coordinates can be deciphered onboard the missile from ground-data relayed to the missile during flight The present method comprises of a horizontal pair and a vertical pair of antennas on the ground and an up-down pair and a right-left pair of antennas onboard the missile. The ground to pairs signals are sinusoidally amplitude modulated in 90° phase difference between the two pairs, causing the transmitted wave polarity to rotate in the modulation frequency. A reference pulse is transmitted from the ground whenever the wave polarity vector crosses a prescribed ground antenna direction, thereby enabling the missile to measure its body up, down, right and left directions relative to earth up, down, right and left directions and to further respectively align them together.