What is the main way for submarines to navigate underwater?1 radar2 satellite system3.GPRS4 inertial system

Answer:

In addition to electronic navigation equipment, there are two types of navigation equipment, but also often equipped on the submarine, generally as a backup or correction positioning accuracyOne is the common instrument of navigation. Such as the magnetic compass, it is affected by the use of needle magnetic field to indicate the position and heading determination range of navigation equipment, the equivalent of the compass; the sextant is horizontal angle measurement principle of celestial altitude and ground targets and the vertical angle of the navigation instrument; log is used to indicate. Speed range and azimuth and distance measuring device; a disk on the periscope can play, the target navigation function. The navigation instrument has the advantages of simple structure, convenient use, although the strong vitality, but the observation accuracy is generally influenced by the weather, is a relatively backward navigation method; also use general instruments are also rising Airlines the periscope or surface, is not conducive to the submarine stealth.

The submarine navigation instrument is more, but mainly rely on the inertial navigation system. Inertial navigation system is the only one capable of launching nuclear submarine navigation and weapons to provide all the necessary data of the equipment, compared with other navigation methods, besides the advantage of high precision, high degree of automation, the most prominent is completely independent, it depending on the inertial components of the navigation, and any other reference materials (such as shore objects and stars and sun, radio waves, etc.) do not have any relationship, so without interference and destruction, concealment and good performance, in the military application has a very important significance.With the help of the inertial navigation system belongs to the electronic navigation instruments of power. The substance of the work, which is arranged on a platform of the accelerometer measured submarine motion acceleration, then through computer to acceleration after a integral speed range obtained by two points, and then calculate the submarine's longitude and latitude, and roll angle, speed, distance and direction of navigation parameters. Submarine launched ballistic missiles, must know the exact location, status and speed to the launch time of submarines, ballistic calculation precision, the ultimate guarantee of fall point accuracy.

When people in the boundless boundless forest, desert or built-up city lost, often do not know where you are, or even do not recognize the driving direction. There is also the problem of nuclear submarines in the war, when tension is not float on outside guidance, nuclear submarine sailing in the vast darkness in the sea, must be armed with blinding "Palace", if you don't rely on special equipment to help, like a blind man on a blind horse ", will be lost.In the nuclear submarine before sailing, responsible for navigation officers and departments have developed a pre route, and the route of the various elements (such as islands, shoals, reefs, water depth, geology, ocean currents, ships etc.) beforehand marked on the chart, the submarine voyage is generally running according to the established route. But nuclear submarines in deep water, can not be observed outside the navigation mark, must have the advanced underwater navigation instrument ready position, constantly revised route, in order to ensure no yaw.

The other is a radio navigation equipment. It is the use of electromagnetic wave information outside the navigation station, can all-weather navigation instrument, the reliability of the equipment itself, such as the positioning speed. Radio direction finder (also known as radio compass), positioning it to the known distribution of coastal radio measurement of azimuth angle, multi for ships in offshore navigation; radio locator, such as Loran C, Omega Navigation System, the former is the use of radio signals, according to the principle of the hyperbolic positioning instrument, but it must have two fixed shore stations. The latter is with the use of navigation system based on the principle of phase delay, the system has 8 launch Taiwan all over the world, with extremely long wavelength synchronous transmission, the submarine can not receive antenna will rise out of the water can receive the signal for positioning; satellite navigation system is used for receiving the radio navigation satellite launch A device for calculating the position of a personThe radio navigation system is the navigation station's launch waves depend on the shore, if the launch pad is damaged or failure, there will be a large blank area; and susceptible to interference, can not provide the ship heading and attitude information. Although the global coverage of satellite navigation system positioning, high precision, subject to the antenna rises to the surface of the water above, its safety is still questioned by other countries; if the use of satellite, no autonomy.