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Celestial Navigation, Doppler and Altimeter Radars topics include: Doppler radar, radar altimeter, stellar inertial navigation theory and stellar sensor design.
Celestial navigation, also known as astronavigation, is the practice of using stars and other celestial bodies to determine a navigator's position. It is one of the oldest human arts. Celestial navigation is useful on the open ocean, where there are no landmarks. It is also used by hikers, backpackers, and hunters. Celestial navigation uses the positions of celestial bodies, such as the sun, moon, and planets, as navigation beacons to calculate the position of the observation point. The positions of celestial bodies in the inertial frame are known and can be tabulated in the published nautical or air almanac almanacs. Only four of the planets are commonly used for celestial navigation: Venus, Mars, Jupiter, and Saturn.
A radar altimeter is an instrument that measures elevation, usually from mean sea level, by measuring the amount of time an electromagnetic pulse takes to travel from an aircraft to the ground and back again. A delay/doppler radar altimeter (DDA) is a new type of radar altimeter that uses delay compensation, which improves measurement precision and tracking accuracy.
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