The itinerary card is one of the more important travel credentials, and many people use it when they go out, especially across regions and cities. So what is the basis of the positioning of the card? The first thing you need to do is to get a good look at what you're getting into, and what you're getting into. Here is a quick and small with the editor to understand the relevant knowledge!

What is the basis for the positioning of the card?

1, the trip card uses the communication between the cell phone and the base station. The cell phone can be moved to any place at will. As long as it can communicate with the base station, it can interact with data. The coverage distance between base stations is about 30 kilometers to 50 kilometers. For complete coverage of cell phone signals, base stations are established every 50 kilometers in a city, creating a spatial range similar to a honeycomb, called cellular communication.

2, communications big data trip card is the China Academy of Communications Sciences and China Telecom, China Mobile, China Unicom three major basic telecom companies to jointly obtain the cell phone "signaling data" for China's 1.6 billion cell phone users to provide free query service, through the user's cell phone base station location. Cell phone users can use this service to check all the places and municipalities they have visited in the past 14 days.

Does a trip card show what time you arrived at a place

No. Trip cards generally only show the places visited, not the exact time.

"The Comms Big Data Itinerary Card shows all the countries (regions) the user has visited in the last 14 days and domestic cities where the user stayed for more than 4 hours.

The "Big Data Itinerary Card" service is provided by the three major telecom operators for public interest inquiries about the places visited by users, and can be used as a supplementary tool for users to prove their personal itineraries. Efforts are being made to expand the reach of the service, but specific access criteria should also follow local government, community and access regulations.

The "Communications Big Data Itinerary Card" service uses base station data. In order to ensure communication continuity and achieve blind coverage, the signals of two base stations at the junction of administrative divisions may overlap, resulting in biased results. In addition, a stay of less than 4 hours in a city will not be recorded. The record of overseas travel requires you to activate the use of international roaming service during your overseas travel. Please contact customer service if there is a serious deviation in the results.

What are the functions of the trip card

As the only app with the function of checking overseas trips, the Epidemic Prevention and Control Trip Card has four major functions:

1. Nationwide general use

Not restricted by domestic provinces, cities and other regions

2. Simple operation

Users can check it by simply scanning the QR code or accessing the WeChat mini program

3. p>3. Safe and reliable

Do not collect personal information such as ID card number, home address, etc., so as to avoid privacy leakage

4. Real and accurate

Based on the data of communication network, no need to fill in by individuals, and dynamically updated

At present, the epidemic prevention and control trip card has been widely used in all aspects of epidemic prevention and control in Customs, transportation, communities, units, etc., to help identify the mobile population.