Why do you know where you've been by scanning travel itinerary code?

Trip code is implemented according to the communication service provided by telecom operators.

As we all know, the normal communication services of mobile phones (call, SMS, Internet access) are realized by the communication base station of operators. The communication base station is what we call a "signal tower". With the cell tower, our mobile phones will have a signal.

Each of us has our own ID number, and the ID number is unique. We can find a person accurately through the ID number. Similarly, each communication base station also has its own "ID number" (base station number), and the base station number of each base station is unique. With the base station number, you can quickly find the location of this base station.

The working principle of trip code is to determine the location we have experienced according to the base station signal received by our mobile phone within 14 days, thus listing our approximate trip. For example, Zhang San has been in a certain place in Hebei 14 days and received signals from two base stations. The base station numbers of the two base stations are 12345/23456 respectively. In this way, when applying for his own travel itinerary code, he must first authorize the operator to inquire, and then through the two base station numbers, he can roughly know that his travel itinerary is somewhere in Hebei.

There is another situation. For example, if you drive from Shijiazhuang, Hebei Province to Beijing, your travel itinerary code will include Baoding, Hebei Province. But in your mind, you have never been to Baoding at all. Because you passed Baoding on your way to Beijing, your mobile phone received the signal from the base station in Baoding area, so there will be a record of Baoding area in your trip.

Of course, run-length encoding is only an auxiliary means of epidemic prevention and control. In the event of an epidemic, the most accurate is the flow adjustment work carried out by professional flow adjustment personnel. Therefore, during the epidemic period, cooperating with the implementation of policies and related work is not only responsible for yourself, but also for society and others. If you have really been to high-risk areas, you should report it truthfully in advance.