©

The symbol for copyright, referring to the exclusive legal right of an author or publisher to publication, production, or sale of the rights to an original literary, dramatic, musical, or artistic work. I, Ray Horak, am the author of this original work, to which Wiley owns the copyright. Please don’t even think about violating their copyright.Thank you. Have a nice day.

The Greek letter delta, , is the symbol for change or difference, as in delta modulation.

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λ

• U.S. Digital Cellular (USDC)
• user
• User Datagram Protocol (UDP)
• user ID (user IDentification)
• user interface (UI)
• username
• user network interface (UNI)
• user plane
• USF (Universal Service Fund)
• USITA (United States Independent Telephone Association)
• USTA (United States Telecom Association)
• US TDMA (United States Time Division Multiple Access)
• UTC (Universal Coordinated Time)
• UTF (Unicode Transformation Format)
• utility
• utilize
• Utopia
• UTP (Unshielded Twisted Pair)
• UTP (Unshielded Twisted Pair)
• (UTRA TDD 1.28Mcps Option)
• UTRA TDD 1.28Mcps Option (UMTS Terrestrial Radio Access Time Division Duplex 1.28
• UV (UltraViolet)
• V
• V.110
• V.120