Tuesday, October 30, 2007

IBOC report from Canada

See the final report of the Canadian Digital Radio Co-ordinating Group.

This committee was formed to study the technical issues involved in introducing IBOC digital radio north of the border. It included:

6 members - representing commercial broadcasters
1 member - representing the Canadian Association of Broadcasters
2 members - representing technical consultants
4 members - from the CBC
6 members - from the Canadian Research Council
5 members - from the Industry Canada and Canadian Radio-television and Telecommunications Commission

The paper is quite educational. A few interesting points:

  • It says "interference-free service for many US stations is achieved only within their 1 mV/m (60 dBµV/m) contours.", then indicates that interference would be more likely in Canada as Canadian stations are protected to their 0.5mV/m contours. Thing is, in the U.S., commercial Class B stations are also protected to their 0.5mV/m (54dBµV/m) contours. These stations are the most important stations in seven of the ten largest U.S. radio markets! - these are the stations the Canadians believe are subject to IBOC interference...

  • Note, at the end, the mention of the large amounts of heat generated by a high-level-combiner IBOC installation. 12kw of heat for one station alone in Toronto.

  • The conclusions reached by the committee:

  • The CRTC should refrain from authorizing permanent IBOC operation until Industry Canada (the technical regulators) has established appropriate technical rules.

  • Industry Canada should refrain from issuing technical rules until they complete additional studies, including field measurements, and establish mitigation measures to deal with harmful interference within the protected service areas of existing stations.
  • Canadian broadcasters should continue to monitor the availability and popularity of IBOC receivers and service in the USA to determine whether IBOC should be pushed for faster implementation in Canada.

  • The committee specifically located harmful interference from IBOC tests on CJBC-FM (90.3) Toronto within the protected contour of CBLA-FM-1 Crystal Beach (90.5).

    There's a lot more "meat" in this report. Take a look.

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