Mobile Phone Systems
A mobile phone is a portable phone that typically can make and receive telephone calls on a short-range radio frequency signal while the user is traveling within a certain phone service zone. The two major cell phone companies – Verizon and AT&T – offer phones that are capable of connecting to the Internet. Some cell phones have GPS technology built-in, so that location information can be accessed by the user. In most cases, a mobile phone uses a Global Positioning System or a GPS chip to determine the latitude and longitude of a certain address. However, the modern mobile phone often comes with additional features that allow it to be used as a PDA, computer, music player, and even a video game.
One of the most popular ways that Americans use mobile devices today is through a cellular telephone system. This system allows people, businesses, and government agencies to use their cell phones to conduct business and make long distance calls while traveling within a specified geographical area. The major advantages to a cellular telephone system include: it reduces the costs of using long distance carriers, it gives users the ability to make or receive unlimited numbers of calls, it provides users with the ability to use the same device for both communication and data purposes, and it allows for users to enter and exit a certain geographic area without having to exit and enter another zone. In some cases, a cellular telephone system allows users to enter and exit a certain geographic area regardless of whether the user has entered or exited the zone before.
Mobile service providers in the United States provide wireless phones, mobile land lines, digital modem connections and digital modems to consumers. There are two types of mobile phone systems: CDMA and GSM. CDMA cellular systems provide voice and messaging functions through base stations, which require direct connection to a specific base station; and GSM cellular systems provide a function such as touch tone and voice dialing functions through a global system. The U.S. Federal Communication Commission (FCC) regulates the operations of U.S. mobile service providers.