ANSI - American National Standards Institute
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On the Air: U.S. Upgrades to Digital Television Signals Nationwide

Standards support transition for both antenna and cable users

New York, Jun 12, 2009

After months of public awareness campaigns, coupon programs, and consumer education, the switch from analog to digital television occurred today in the United States. Digital television carries a number of benefits for consumers, and its transmission is facilitated by many standards in the U.S. and abroad.

For many years, television signals have only been broadcast in analog. More advanced technology now allows networks to use digital signals, which provide clearer reception and allow for a greater number of channels to be broadcast over the air. Additionally, the change will open air waves to firefighters and police so they can better communicate during emergencies.

Where in the world are digital signals used?

Television systems around the globe have been transitioning from analog to digital signals for the past several years. Luxembourg was the first country to move to digital broadcasting, completing the switch in September 2006. Other nations followed, including Sweden, Switzerland, Germany, and now the U.S.

June 12, 2009, marks the official switch to digital for the U.S. Many more nations, including Canada, China, Brazil, and Kenya, have begun the transitioning process as well.

For those Americans who use an antenna to receive television signals on an analog television, a converter box is needed to receive digital signals. An American National Standard (ANS) to guide the manufacturers and users of these converter boxes was developed by the IEEE, a member and accredited standards developer of the American National Standards Institute (ANSI). 1241-2000, IEEE Standard for Terminology and Test Methods for Analog-to-Digital Converters, identifies analog-to-digital converter error sources and lists test methods to perform the required error measurements. The standard provides a basis for evaluating and comparing existing devices, as well as providing a template for writing specifications for the procurement of new ones.

Americans who use cable television services will not need to install an analog-to-digital converter box. A standard developed by the Society of Cable Telecommunications Engineers (SCTE), an ANSI member and accredited standards developer, addresses the requirements of these setups for digital signals. ANSI/SCTE 07 2006, Digital Transmission Standard For Cable Television, describes the framing structure, channel coding, and channel modulation for a digital multi-service television distribution system that is specific to a cable channel.

To learn more about the switch to digital television, visit the National Telecommunications and Information Administration website.

In light of the new requirements of televisions to receive over-the-air signals, many consumers are choosing to purchase new sets that meet digital requirements. For more information on recycling discarded televisions, see this ANSI news item.