Is the accuracy of the 4g lte gps tracking device determined by the GPS module?

4g lte gps tracking device

The 4g lte gps tracking device can prevent theft and ensure the safety of the car. After installing it, the car owner can use the computer or mobile phone to check the car positioning information on the APP or management platform anytime, anywhere. Why can 4g lte gps tracking device be able to locate? In fact, it is because of its built-in GPS positioning module. The GPS positioning module uses special high-tech technology, which is mainly used for position positioning. It is one of the important components of GPS global positioning system, which determines the effect and performance of positioning terminal products. Therefore, GPS positioning module is very important.

1. Principle of GPS positioning module

Twenty-four communication satellites revolve around the earth at an altitude of 12,000 kilometers at a periodic frequency of 12 hours, so that at any instant, any point on the ground can monitor more than 4 communication satellites at the same time.

Since the position of the satellite is known, in the monitoring, the distance from the satellite to the receiver, using the formula in the three-dimensional coordinate, according to the three satellites, to establish three equations, and solve the position of the observation point (X, Y, Z). Special attention is the difference between the clock of the communication satellite and the clock of the receiver, so there are actually 4 unknowns, X, Y, Z and the clock difference, so we need a fourth satellite to establish 4 equations to solve .

2. How to improve the accuracy of GPS module

Because the receiver can generally lock 4 or more satellites, at this time, the receiver can be divided into groups according to the constellation distribution of the satellites, a group of 4, and then use its algorithm to filter out the one with the lowest error value. Groups are used as positioning, thereby improving accuracy.

There is an error value between the orbit and time of the satellite, and the influence of the atmospheric troposphere and ionosphere on the signal makes the accuracy of civil GPS only 10 meters. In order to improve the accuracy, differential GPS technology is generally used, a base station is established for GPS observation, and the precise coordinates of the base station that have been mastered are used to compare with the observed values, so as to calculate the correction number and disclose it to the public. After the receiver receives the correction number, it compares it with its own observation value, eliminates most of the error values, and obtains a more accurate position. Experiments show that using differential GPS, the accuracy can be improved to 5 meters.

4g lte gps tracking device


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