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Online Course from Stanford University in 65 parts (about 16 hours).
This course will teach you the fundamentals of how GPS works and introduce you to the diverse range of uses of satellite navigation in all aspects of our lives.
Navstar GPS User Equipment Introduction by United States Coast Guard
The Navstar Global Positioning System (GPS) is a space-based radio-positioning and timetransfer system. GPS provides accurate position, velocity, and time information to an unlimited number of suitably equipped ground, sea, air and space users.
Navstar GPS Space Segment/Navigation User Interface by GPS.GOV
This Interface Specification (IS) defines the requirements related to the interface between the Space Segment (SS) of the Global Positioning System (GPS) and the navigation User Segment (US) of the GPS for radio frequency (RF) link 1 (L1) and link 2 (L2).
Global Positioning System; Wikipedia
The GPS does not require the user to transmit any data, and it operates independently of any telephonic or internet reception, though these technologies can enhance the usefulness of the GPS positioning information.
It seems many people are confusing the information they see on flight trackers like FlightAware and Flight Radar. These trackers can rely on ground based installations that receive information from the Aircraft, Radar and ADS-B. When the aircraft flies out of range of a ground station it will appear to "drop off the radar" on these simple flight trackers. The GPS is a one way system that provides location information to the aircraft and pilot. It has no tracking capability at all.
GPS works fine everywhere in the world.
I flew back to Australia last night as a passenger with Qantas. I had requested an upper deck window seat and purchased a second GPS and a magnetic compass to conduct more analysis during the flight. I copied the filed flight plan into my Foreflight App so I could follow the route accurately. (If you sign into FlightAware you can see the filed plans for each flight). The magnetic compass is totally unreliable inside the cabin.
Both Bad Elf GPS units worked flawlessly from the USA to Australia. Even in the middle of the Pacific Ocean crossing the Equator.
The World Geodetic System WGS84 is the Globe Model implemented in GPS and is used not only by Google Earth and other map applications, but is also the model used for flight planing and aircraft navigation. It has cm accuracy worldwide. Using Wide Area Augmentation System WAAS it is used to fly thousands of km, even without visibility to the ground, to find the destination runway to m accurcy everywhere on earth.
I show how GPS and the WGS84 model is used in daily flight planing and navigation.
Measuring the radius of the earth in the Display Geo Data App at the Route 80 at the Great Salt Lake Desert near Salt Lake City (Bonneville Salt Flats, Utah) from GNSS data gathered by the geodetic surveyor .
An array of ring lasers provides the first continuous measurement of Earth’s motion from a single location.
Earth’s rotational velocity and axis orientation experience constant fluctuations caused by changes in the planet’s interior, in the oceans, and in the atmosphere. Researchers now report the first continuous measurements of these miniscule fluctuations, using an arrangement of four laser gyroscopes buried underground in Germany. Data from this new facility will be important for maintaining up-to-the-moment accuracy for GPS-based navigation.
See also How to Detect the Chandler and the Annual wobble of the Earth with a Large Ring Laser Gyroscope by K. U. Schreiber, T. Klügel, J.-P. R. Wells, R. B. Hurst and A. Gebauer, Technische Universitaet Muenchen, Forschungseinrichtung Satellitengeodaesie
Some airports use GNSS (GPS) non precision approach (NPA) and ILS (radio beacon) precision approach (PA) vertical guidance for the final approach to the runway. ILS is a straight line approach, while GNSS is a curved line approach following the curvature of the earth on a glide slope angle. In the calculations of the distance from the runway to the final approach point the curvature of the earth is taken into account for both approach variants.
The United States Standard for Area Navigation (RNAV) (pdf); page 66
United States Standard for Terminal Instrument Procedures (TERPS) (pdf); page 79 and paragraph 98:
98. Precise final approach fix (PFAF). The PFAF is a calculated WGS84 geographic position located on the final approach course where the designed vertical path (NPA procedures) or glidepath (APV and PA procedures) intercepts the intermediate segment altitude (glidepath intercept altitude). The PFAF marks the beginning of the FAS. The calculation of the distance from LTP to PFAF includes the earth curvature.
Great circle route passes very near Antarctica and because the circumference of the earth along a latitude line there is so short, the airplane was fast enough to follow the sun for some hours.made a flight around the Globe. With his GPS device he recorded the whole flight. This video is about the flight from Sydney to Johannesburg. Because the
The Rainy Lake Experiment was designed to show, how we can figure out the shape of the earth, Flat or a Globe, by observing and measuring a clever arrangement of targets over a distance of 10 km, taking terrestrial refraction into account and using modern equipment.
The experiment is an advanced version of the Bedford Level experiment executed in 1838. The Experiment leads to the conclusion that the earth must be a Globe with a radius of 6371 km.