Abstract: A system for locating forward observation posts with respect to a base ston. A continuous electromagnetic wave with frequency f.sub.o is transmitted from an artillery projectile or missile in flight. In addition, a relative time code is transmitted on the same or a separate carrier frequency either from the projectile or from a ground station. The frequency f.sub.o of the electromagnetic wave from the projectile or missile is doppler shifted above or below its basic frequency due to the velocity of the projectile. This doppler signal f.sub.d always goes through its basic frequency f.sub.o or zero doppler at a point which is representative of and identifies an observer's position in the horizontal or subtrack direction of the projectile. This occurs regardless of the observer's distance away from the subtrack. Thus, all observers on a given perpendicular to the subtrack observe f.sub.o or zero doppler at the same time. To locate a specific observer, two projectiles or missiles must be fired.

Abstract: A method and apparatus for measuring the extent of camouflage applied to a arget is disclosed. The apparatus includes a direct electronic Fourier transform device responsive to first and second conditions of camouflage of a target for producing spectra signals of first and second limited Fourier transforms, respectively. Each of the spectra signals has a plurality of amplitude and principal frequency components, and a base clipper circuit is provided for deleting the spectra signal amplitude components below a given value. A radio frequency voltmeter and a first analog-to-digital converter cooperate to produce digital signals corresponding with the magnitude of the amplitude components. Similarly, a radio frequency frequency meter and a second analog-to-digital converter cooperate to produce digital signals corresponding with the principal frequency components.

Abstract: A system for locating forward observation posts with respect to a base ston. A continuous electromagnetic wave with frequency f.sub.o is transmitted from an artillery projectile or missile in flight. In addition, a relative time code is transmitted on the same or a separate carrier frequency either from the projectile or from a ground station. The frequency f.sub.o of the electromagnetic wave from the projectile or missile is doppler shifted above or below its basic frequency due to the velocity of the projectile. This doppler signal f.sub.d always goes through its basic frequency f.sub.o or zero doppler at a point which is representative of and identifies an observer's position in the horizontal or subtrack direction of the projectile. This occurs regardless of the observer's distance away from the subtrack. Thus, all observers on a given perpendicular to the subtrack observe f.sub.o or zero doppler at the same time. To locate a specific observer, two projectiles or missiles must be fired.