Cellular: In order to accommodate a large number of users, a geographical area can be divided into many small communities. Instead of using a single high-power transmitter, each cell is served by a low-power base station. Due to the limited range of influence that these base stations can have, the same spectrum can be reused in another cell far away from a certain distance. The reuse of frequency and the operation of handover together form the main body of the concept of cell (cellular). A honeycomb is an economical and efficient structural method, and the English name for a cellular phone is Cell phone Cell has the meaning of a cell, and it is not difficult to imagine one of its patterns: infinite division. In architecture, honeycomb is an economical and efficient structural approach. Can mobile networks adopt the same approach and then use different frequencies in adjacent communities, while using the same frequency in distant communities. This effectively avoids frequency conflicts and allows the same frequency to be used multiple times, saving frequency resources. This theory cleverly solves the contradiction between limited high-frequency frequencies and the demand of numerous high-density users, as well as the problem of automatic channel conversion across service coverage areas. The cellular mobile phone system can accommodate an infinite number of users, and mobile phones in any location within this area can be connected to the public telephone network through wireless channels and switches, truly enabling communication with any place in the world at any time. At the same time, automatic and semi-automatic switching can be carried out between two or more mobile switching offices as long as the format is the same, Thus expanding the range of mobile station activities. Therefore, theoretically speaking, a cellular mobile phone system can accommodate an infinite number of users