Các tế bào connetion P2

CELLULAR PHONE EQUIPMENT There are three parts to a cellular phone system: the cellular telephone, or cellphone; the cell site, which receives and transmits radio signals from and to your phone; and the MSC, or Mobile Switching Center, which links cellphones to established conventional telephone services. The relationship among these is illustrated in Figure 2.1. THE CELLULAR TELEPHONE The standard portable cellular telephone is a one-piece unit that serves as the handset, and includes a dial pad or ‘‘keypad,’’ display, microphone, miniature speaker or earpiece, a miniature radio receiver and transmitter or transceiver, antenna, and a removable, rechargeable battery....