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Air navigation part one introduction to the earth
Air navigation part one introduction to the earth




air navigation part one introduction to the earth

Moreover, the price increases exponentially as the precision is enhanced. Because an INS is a PMM, the error increases with time. Furthermore, INS can avoid GPS jamming issues. Although GPS offers a precise navigation system, it has limitations in space, deep seas, tunnels, and similar places because the GPS operates only when it can receive signals from the satellite. The Inertial Navigation System is a stand-alone navigation system that continuously calculates the position, direction, and velocity of the main body through its own accelerometer, rotation sensor, and arithmetic unit, without receiving any external information. Deep space explorer orbit compression and transmission were proposed using B-spline. For Low Earth Orbit satellites, the deviations between nominal and real orbit are compressed in the form of Fourier coefficients by using the periodic characteristics of the trajectory. Therefore, the cost of communication can be reduced by compressing orbital data. However, Deep space communication is restrictive and expensive. Generally, a precise determination of orbit is made on the ground, and the information is then transmitted to the spacecraft periodically.

air navigation part one introduction to the earth

The orbital equation used in spacecraft is represented by a nonlinear differential equation containing multiple perturbation terms, which makes the determination of orbit numerically complex. In the case of spacecraft, auxiliary navigation systems using data compression were proposed due to the unpredictable space environment and limited communication. The navigation equipment in ground vehicles and the orbit propagator in spacecraft are designed to complement each other, considering the properties of tools such as the INS/GNSS. However, there may be some restrictions on communication. EDMs are relatively cheap and the accuracy is pre-defined according to sensor. However, information can be obtained for three axes (X, Y, and Z) this is a stable configuration as no communication problems are incurred. The accuracy of PMMs is exponentially proportional to the cost, and the error increases over time. Methods to determine longitude and latitude using polar stars or the sun considered as EDMs, which is utilized in the spacecraft nowadays. The global navigation satellite system (GNSS) is an excellent representative of EDMs. They determine the existing position of an object by measuring various changes in its state, such as velocity and acceleration. Examples of PMMs are inertial navigation systems (INS) and dead-reckoning navigation. Navigation is classified into two categories in this study: physical model-based methods (PMMs) and external data-based methods (EDMs). In the modern sense, navigation is mechanical devices equipped in ground vehicles, ships, and aircraft to determine their positions. As a result of modern developments in science and technology, exact positions and speeds are determined using equipment such as artificial satellites, global navigation satellite system (GNSS), inertial navigation systems (INS), etc.

air navigation part one introduction to the earth

In the pre-modern era, direction and position were determined using an altazimuth, a compass, and a map these are now considered primitive forms of navigation. Navigation refers to the method of determining aspects such as position, speed, and direction during travel.






Air navigation part one introduction to the earth