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  2. AN/FPS-16 Instrumentation Radar - Wikipedia

    en.wikipedia.org/wiki/AN/FPS-16_Instrumentation...

    The radar provides data and range safety for missile launches. This radar, along with its data system, is used for tracking the Minuteman III ICBM. The AN/FPS-16 is a highly accurate ground-based monopulse single object tracking radar (SOTR), used extensively by the NASA crewed space program

  3. High Accuracy Radial Velocity Planet Searcher - Wikipedia

    en.wikipedia.org/wiki/High_Accuracy_Radial...

    The HARPS can attain a precision of 0.97 m/s (3.5 km/h), [2] making it one of only two instruments worldwide with such accuracy. [citation needed] This is due to a design in which the target star and a reference spectrum from a thorium lamp are observed simultaneously using two identical optic fibre feeds, and to careful attention to mechanical stability: the instrument sits in a vacuum vessel ...

  4. Envelope (radar) - Wikipedia

    en.wikipedia.org/wiki/Envelope_(radar)

    Pulse-Doppler radar and Continuous-wave radar are required for high performance in this area because these exclude low-velocity reflections. This is a critical measure of performance for the Littoral zone and land-based radar. Prevailing winds of about 15 mile/hour cover most of the surface of the earth. This constantly stirs up debris into the ...

  5. Geostationary orbit - Wikipedia

    en.wikipedia.org/wiki/Geostationary_orbit

    A geostationary orbit, also referred to as a geosynchronous equatorial orbit [a] (GEO), is a circular geosynchronous orbit 35,786 km (22,236 mi) in altitude above Earth's equator, 42,164 km (26,199 mi) in radius from Earth's center, and following the direction of Earth's rotation.

  6. Global Positioning System - Wikipedia

    en.wikipedia.org/wiki/Global_Positioning_System

    As opposed to the year, month, and day format of the Gregorian calendar, the GPS date is expressed as a week number and a seconds-into-week number. The week number is transmitted as a ten- bit field in the C/A and P(Y) navigation messages, and so it becomes zero again every 1,024 weeks (19.6 years).

  7. Geosynchronous orbit - Wikipedia

    en.wikipedia.org/wiki/Geosynchronous_orbit

    A geostationary equatorial orbit (GEO) is a circular geosynchronous orbit in the plane of the Earth's equator with a radius of approximately 42,164 km (26,199 mi) (measured from the center of the Earth). [21]: 156 A satellite in such an orbit is at an altitude of approximately 35,786 km (22,236 mi) above mean sea level. It maintains the same ...

  8. GPS signals - Wikipedia

    en.wikipedia.org/wiki/GPS_signals

    A time of interval (TOI): the integer number of 18 second periods elapsed since the period represented by the current ITOW to the beginning of the next message. It has range 0 to 399 (inclusive) and requires 9 bits of data. TOI is the only content of subframe 1. The week number and ITOW are contained in subframe 2 along with other information.

  9. Inertial navigation system - Wikipedia

    en.wikipedia.org/wiki/Inertial_navigation_system

    Where f is specific force, is angular rate, a is acceleration, R is position, ˙ and V are velocity, is the angular velocity of the earth, g is the acceleration due to gravity, , and h are the NED location parameters. Also, super/subscripts of E, I and B are representing variables in the Earth centered, inertial or body reference frame ...