Composition of Jiangmen on-board Navigator:

1. Space

The space part of Jiangmen on-board navigator is composed of 24 satellites (21 operational satellites and 3 standby satellites). It is located 20200km above the earth's surface and evenly distributed on 6 track surfaces (4 for each track surface) The track inclination is 55 °. The distribution of satellites makes it possible to observe more than four satellites anywhere in the world and at any time, and the navigation information can be pre stored in the satellites. Due to atmospheric conflicts and other problems, the navigation accuracy of GPS satellites will gradually decline with the passage of time.

2. Ground control system

The above ground control system is composed of monitor station, master monitor station and ground antenna. The main control station is located in Colorado spring, Colorado, USA. The above ground control station is responsible for collecting the information transmitted by the satellite and calculating the satellite ephemeris, relative interval and atmospheric calibration data.

3. User equipment

The built-in GPS satellite receiver module of the GPS vehicle terminal is used to receive satellite navigation message information, record vehicle condition information with other external data sensors and using equipment, and then process it into a message through the information processing module, and send it to the monitoring center through the Internet through GSM / CDMA network, GPRS / cdmad and other transmission methods. The monitoring center is programmed by a series of software programs equipped The line is analyzed and stored in the system database, and the vehicle orientation information is displayed through the electronic map, so as to achieve the purpose of visual monitoring.

Through the system, the monitoring center can send voice or text dispatching instructions, notices and other information to the on-board terminal and relevant connecting equipment (such as electronic screen). On this basis, according to the needs of industry use and practical handling, the system also provides various customized handling reports (alarm log accounting report, distance accounting report, etc.) , so as to improve the operation efficiency of vehicles and other mobile policies, ensure safe operation and production, improve the comprehensive service quality, and improve the scientific management level.

Operation principle of on-board GPS locator:

The operation principle of GPS positioning system is that the ground main control station collects the observation materials and meteorological information of each monitoring station, calculates the ephemeris and satellite clock correction number of each satellite, edits the navigation message according to the specified pattern, and injects these information into the GPS satellite through the ground injection station.

The mission of the GPS signal receiver is to capture the signals of the satellites to be measured selected according to a certain satellite height cut-off angle, track the operation of these satellites, transform, amplify and process the received GPS signals, so as to measure the transmission time of the GPS signal from the satellite to the receiver antenna, interpret the navigation messages sent by the GPS satellite, and calculate the measured data in real time The station's three-dimensional orientation, orientation, and even three-dimensional velocity and time.

According to the positioning method, GPS positioning is divided into single point positioning and relative positioning (differential positioning). Single point positioning is the method to confirm the receiver's orientation according to the observation data of a receiver. It can only use pseudo range observation measurement, which can be used for general navigation positioning of vehicles and ships. Relative positioning (differential positioning) It is a method to confirm the relative orientation between observation points according to the observation data of more than two receivers. It can select either pseudo range observation or phase observation. Phase observation value shall be selected for relative positioning in geodetic measurement or engineering measurement.

When measuring and positioning, the user can use the ephemeris stored in the receiver to obtain the approximate azimuth of each satellite. According to these data and their own azimuth, the accounting machine selects four satellites with a large angle between the satellite and the user's connecting line as the observation policy.

During positioning observation, the receiver uses the information generated by the code generator to correlate with the signal received by the satellite, and measures the pseudo range between the user and the satellite according to the time scale and subframe count of the navigation message. Three observation equations are listed for the corrected pseudo range, the input initial data and the observation values of the four satellites, so as to solve the orientation of the receiver and convert the required information Coordinate system to achieve positioning purpose.

GPS positioning system is also known as GPRS. In short, GPS positioning system relies on a mobile phone card built in your vehicle terminal to complete positioning through mobile phone signal transmission to the background. GPS terminal is the background, which can help you complete one click navigation, background services, and other human services. GPS positioning system is used in more and more industries with the development of society, and it plays an important role The effect of early supervision and later handling shall be uniformly distributed to facilitate handling, improve our operation efficiency and reduce costs.

Effect of on-board GPS locator:

1. Vehicle tracking function uses GPS and electronic map to show the practical orientation of the vehicle in real time, and can zoom in, zoom out, restore and change the map at will; it can move with the policy to keep the policy on the screen all the time; it can also track multiple windows, multiple vehicles and multiple screens. Using this function, important vehicles and goods can be tracked and transported.

2. Provide travel road planning and navigation function supply travel road planning is an important auxiliary function of car navigation system, which includes active route planning and artificial route planning. Active route planning is that the driver confirms the starting point and destination, and the accounting computer software actively plans the best driving road according to requirements, including the fastest road, the simplest road and passing through The calculation of the road with the least number of freeway sections. Manual route planning is that the driver plans the starting point, ending point and passing point according to his own destination, and actively establishes the road library. After the route planning is completed, the display device can display the planned road on the electronic map and show the operation path and operation method of the car together.

3. The information query function provides users with primary object databases, such as tourist attractions, hotels, hospitals, etc., and users can display their location on the electronic map. Together, the monitoring center can query the location of any policy in the area using the monitoring console, and the vehicle information will be displayed on the electronic map of the control center in digital form.

4. Traffic command function: the command center can monitor the operation status of vehicles in the area and reasonably dispatch the monitored vehicles. The command center can also talk with the tracked policy at any time and handle it.

5. Emergency help function through GPS positioning and monitoring management system, it can provide emergency help to vehicles in case of danger or accident. The electronic map of the monitoring station shows help information and alarm policy, plans the optimal help scheme, and reminds the personnel on duty with alarm sound and light for emergency treatment.

The article comes from the brand of vehicle navigatorhttp://leakdamagelaws.com