In July, 2008, NPR Labs completed a monumental 18-month study projecting the consequences of interference between HD Radio and station analog broadcast signals, as well as HD Radio’s overall success in meeting coverage expectations and needs.

The CPB-funded study, “Digital Radio Coverage and Interference Analysis” (or “DR. CIA” for James Bond fans), produced the first field-validated HD Radio FM coverage prediction model, which allowed us to create – for the first time – maps showing what each station’s interference-limited coverage area would be if it were broadcasting in both analog and digital. The study also reached important conclusions about the effects of raising HD Radio’s current 1% power level to the 10% power level, a proposal that several commercial broadcast groups, the NAB and others have recommended to the FCC.

Download the executive summary
Download the full report

See the IBOC DAB Interference Maps and Population Reports for 49 Public Radio Stations here.