### Doppler Radar

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.