Tuesday, October 9, 2007

HD Radio

http://en.wikipedia.org/wiki/Hd_radio

There is a general disinterest amongst consumers in the new Digital HD Radio. According to a survey by Bridge Ratings, when asked the question, "Would you buy an HD radio in the next two months?" only 1.0% responded "yes".[23] Some engineers have also expressed distrust or dislike of the new system.[24]

HD Radio tuners have been noted as being very insensitive, making reception problematic. In hybrid mode, the HD Radio signal is 1/100th the power of a station's analog signal. For this reason, the HD Radio signal will sometimes drop out and the receiver will revert to analog mode. This can be especially problematic in fringe areas, where the digital signal may frequently be lost. In addition it has been noted that the analog section displays poor reception capabilities compared to older non-digital models.[25]

Whereas DRM and DAB are controlled by non-profit consortiums with members from more than 30 countries, iBiquity ultimately has control over HD Radio receiver-manufacturer licensing[26] and broadcaster licensing.[27] HD Radio has been officially adopted only by the US and Brazil. iBiquity has stated in PR articles that countries evaluating HD Radio include Canada, France, Mexico, New Zealand, the Philippines, Switzerland, and Thailand.[26][27] However as of mid-2007, Canada and Switzerland have officially selected, or are also testing, the Digital Audio Broadcasting standard, and France has already chosen DAB. iBiquity and other sources do not explicitly state in published articles what technically comprises the "evaluation", whether there are ongoing or elapsed test transmissions, and the quantity or power of transmitters.

HD Radio has been criticized for being incompatible with the standards selected by most other countries; hence overseas travel with an HD Radio, or the sale of radios to or from countries that don't use HD Radio is not possible. Manufacturers presently must design and build separate radios for the U.S. market. For broadcasting on frequencies below VHF (including Shortwave and AM/Medium Wave), most countries (and the standards organizations ITU, IEC, and ETSI) have adopted the Digital Radio Mondiale system, abbreviated "DRM" (not related to Digital Rights Management). For VHF and higher frequencies, a majority of countries have adopted or are evaluating the Digital Audio Broadcasting, abbreviated "DAB" system (see "Regional implementations of DAB" in Digital Audio Broadcasting).

The U.S. FCC selected HD Radio as the official digital radio system in 2002, and without provision for compatibility with DAB (ratified by the ITU-R standardization body in 1994) and DRM (ITU ratified April 2001). Thus, although an analog radio from one continent can be taken to another and it will work to some degree, the differences between HD Radio and DAB/DRM make listening to the other system impossible.

Unlike subscription-based satellite radio, the content of HD Radio stations is subject to FCC regulation.

Unlike regular car radios, which come fitted as standard equipment with virtually all automobiles, HD Radio requires consumers to purchase a new radio costing more than $100.