1. The principle of wireless geomagnetic detection technology.
Without the disturbance of foreign objects, the earth's magnetic field is in a relatively stable state. When an object passes by or stops on the top, the magnetic field value will undergo some subtle changes. Disturbance is relatively obvious. Wireless geomagnetism detects motor vehicles through the analysis of changes in the earth’s magnetic field. When there is no motor vehicle on the local magnetism, the earth’s magnetic field is in a relatively stable state, and the system defaults to no car; when a motor vehicle passes over the geomagnetism When the earth's magnetic field changes due to time, the system will consider that there is a car and upload this data through the wireless communication protocol.
2. Working principle of wireless geomagnetic detection system
The presence and passage of vehicles are detected by the wireless geomagnetic detector embedded in the road, and the detection data is transmitted to the nearby gateway in real time using low-power radio communication technology (if the signal transmission distance is affected, the repeater will be increased), and the data will reach the gateway Later, it can be transmitted to the cloud data management platform or local server via wired or wireless.
Three, the main function
Provide data basis for traffic management departments and decision makers;
Detect traffic information, such as: traffic volume, speed, queue length, etc.;
Detect vehicle information: such as vehicle speed, vehicle length, distance between vehicles, etc.;
Link with intersection data to release real-time traffic information;
Provide a variety of solutions, such as: signal control, traffic information collection, variable lanes and other application solutions; 
4. Comparative advantages of other implementation solutions
At present, the main vehicle detectors used on traffic roads at home and abroad are: coil car detectors, video car detectors and microwave car detectors. The effect of these vehicle detectors in practical applications is affected by various factors, and there are the following problems: 
V. Application scenarios of wireless geomagnetic detection
According to usage data collection scenarios, it is mainly divided into two categories:
1. Traffic flow data collection: high-speed road condition detection, urban road condition detection, road bayonet capture and ETC lanes, incoming traffic warning, tunnel congestion control, etc.;
2. Parking information collection: parking space guidance technical solutions, fire channel blockage warning solutions.
6. Application of FETMX6UL-C core board as a wireless gateway
1. The network port transmits data to the cloud platform (customer server, operator cloud platform)
2. 4G transmits data to the cloud platform (customer server, operator cloud platform)
3. 232, 485, 422, USB to communicate with the local server (the local server has various interfaces)
4. IO multi-channel: lever-lifting control, information reminding of incoming vehicles, etc.
5. Serial port: wireless module LORA, ZIGBEE.