Introduction
IS-54 stands for Interim Standard-54, which is a mobile communication standard employing digital technology. It was standardized by Electronic Industries Alliance (EIA) and Telecommunications Industry Association (TIA) together. It later became an American National Standard when it got approved by the American National Standards Institute (ANSI). When an interim standard becomes an American National Standard, the IS designator is dropped. The ANSI designation of IS-54 is ANSI/TIA/EIA-627, but this standard is still popularly referred to as IS-54.
IS-54 maintains compatibility with Advanced Mobile Phone System (AMPS) in many ways. It is a digital extension of AMPS and so it is also quite widely known as Digital AMPS (D-AMPS). Another name for IS-54 is United States Digital Cellular (USDC). But sometimes D-AMPS and USDC also refers to the other prominent interim standard IS-136.
Read more about this topic: Digital AMPS
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