How to use the car radio

Introduction to Car Radio - Principles
GPS is composed of three major components: space satellites, ground monitoring, and user reception. In space, there are 24 satellites forming a distribution network, each located in 6 Earth's quasi synchronous orbits with a tilt angle of 55 ° and a distance of 20000 kilometers from the ground. There are 4 satellites in each orbit. GPS satellites orbit the Earth every 12 hours, enabling any location on the Earth to simultaneously receive signals from 7-9 satellites. There is a total of 1 main control station and 5 monitoring stations on the ground responsible for monitoring, telemetry, tracking, and control of satellites. They are responsible for observing each satellite and providing observation data to the main control station. After receiving the data, the main control station calculates the accurate position of each satellite at each moment and transmits it to the satellite through three injection stations. The satellite then transmits this data to the ground through radio waves to the user's receiving device. Only after more than 20 years of research and experiments on the GPS system and a cost of 30 billion US dollars, the 24 GPS satellite constellation with a world coverage rate of 98% were officially deployed in March 1994. Now the application of GPS system is not limited to the military field, but has developed into various fields such as vehicle navigation, atmospheric observation, geographical survey, ocean rescue, manned spacecraft protection and detection.
Introduction to Automotive Navigator - Composition
The operation of the GPS navigator also requires a car navigation system. Having a GPS system alone is not enough. It can only receive data sent by GPS satellites, calculate users' three-dimensional position, direction, and motion speed and time information, and has no path calculation ability. In order for the GPS receiving device in the user's hands to achieve route navigation function, a complete car navigation system including hardware devices, electronic maps, and navigation software is also needed. The hardware of the GPS navigator includes components such as chips, antennas, processors, memory, screens, buttons, speakers, etc. However, as of now, there is not much difference in hardware between GPS car navigators in the market, and it is difficult to distinguish who is good from who is bad with built-in software maps. Currently, there are eight mapping companies in China engaged in the surveying and development of navigation map software, such as 4D Tuxin, Kailide, Daodao Tong, Chengjitong, After several years of continuous development and improvement, we have been able to provide quite good navigation map software. To summarize, a complete GPS car navigator consists of nine main components: a chip, antenna, processor, memory, display screen, speakers, buttons, expansion function slots, and map navigation software.