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GPS | Global Positioning System is a system of |
| satellites, computers, and receivers able |
| to determine the latitude and longitude |
| of a specific receiver on Earth. Position |
| is calculated using time and distance. |
IS 2000 | Type of digital signaling. It's the second |
| generation of CDMA digital cellular, an |
| extension of |
| signaling types have to do with pilot |
| signal and links to provide more traffic |
| channels, and control protocols. |
NAM | Number Assignment Module is how the |
| phone stores the phone number and its |
| electronic serial number. A multiple |
| NAM phone can register with multiple |
| service providers and be set to |
| automatically switch between |
| programmed phone numbers for service |
| provider areas. |
SID | System Identification is a number |
| transmitted by base stations to identify a |
| wireless system which conforms to a |
| TIA cellular or PCS standard. |
| SID is used by mobile phones to |
| recognize when they are in their home |
| system and can be used for billing |
| purposes as a unique identification of |
| the serving system. |
SMS | Short Message Service is a service |
| available on most digital mobile phones |
| to send messages between phones or |
| other devices. Messages are routed a |
| Short Message Service Center (SMSC), |
| which attempts to send the message |
| and, if unsuccessful, possibly retry at a |
| later time. Message delays or message |
| loss is possible, especially when |
| sending between networks. Users can |
| request delivery confirmation reports. |
TTY | Teletypewriter. An electromechanical |
| typewriter that either transmits or |
| receives messages coded in electrical |
| signals. A phone with TTY support is |
| able to translate typed characters to |
| voice or translate voice into characters |
| to display on the TTY. |