The use of microwave signals reflected by a moving object to determine its radial speed very accurately.

Johan Christian Andreas Doppler, Austrian mathematician and physicist, 1803-1853, who described the Doppler effect.

Ballistics

The science of projectiles in flight, taking account of factors such as Velocity, Gravity, Spin, and Air Density.

Sir Isaac Newton, English mathematician and scientist, one of the foremost scientific minds of all time, 1642 to 1727. Formulated Newton’s laws of motion.

Signal Processing

Signal processing of Doppler signals to determine the velocity and other characteristics of the projectile’s flight.

Jean Baptiste Joseph Fourier, French mathematician 1768-1830, developed methods to solve partial differential equations used in modern day image processing.

Phased Array Antenna

Using an arrangement of multiple antennas to rapidly determine the direction of a radar target.

Luis Walter Alvarez, American physicist and Nobel Prize winner, 1911-1988, developed phased array designs in World War II.