How do pagers work?

Answer 1

For beeper users, the paging process starts when the beeper or paging device is purchased. At the time of sale, the paging carrier enters identifying information, such as the beeper's electronic serial number, into its network database. From that time forward, as long as the customer pays the bill and the database entry is not modified, messages sent at the frequency the beeper monitors and containing the beeper's ESN will be picked up and relayed by the paging device When a paging customer receives a message, that message has to originate with a sender. While the message may originate from a system on the paging network itself--as is the case with automated sports, stock, and news updates, or payment reminders--most messages originate from human callers. Depending on the type of beeper used, the caller can dial in to an automated messaging center where he can enter a numeric code, or dial into a live operator who translates a voice message into an electronic message. Some newer beepers use automated software to convert voice messages, and others simply take a voicemail recording and alert the customer to a waiting message. Regardless of how the message is captured, the caller simply delivers the message then hangs up; the rest is handled by the paging network and the beeper itself. Once a message is received by the paging network carrier, it must be prepared for transmission to the subscriber. In most modern systems, the message is received and stored electronically--even if entered by a human operator--so little to no manipulation is required to convert the message to a digital representation. For transmission, the electronic message is converted into radio waves, encoded to contain the beeper's ESN, and then broadcast from the paging carrier's network towers at the frequency monitored by the paging device. Because paging networks have many subscribers, beepers are constantly receiving and discarding messages. Each message that is broadcast from the network is received by the paging device, evaluated to see if the associated ESN is contained, then discarded if the correct ESN is absent. After a caller enters a message and that message is broadcast to the beeper, though, the appropriate ESN is encoded and the paging device must take action. Received via radio waves, the beeper must convert the incoming message back into an electronic signal before it can evaluate the ESN and display the message. If the encoded ESN matches the beeper's unique serial number, the device displays the incoming message on its screen and either vibrates, beeps, lights up, or produces a combination of these effects to alert the subscriber to the incoming message.