NPR, iBiquity reach a deal on HD power increase

iBiquity Digital and NPR announced an agreement for managing an HD Radio power increase that will significantly improve reception of HD Radio signals. The two organizations are jointly presenting their recommendations to the FCC 11/5 and encouraging the Commission to move to adopt the power increase quickly.

iBiquity CEO Bob Struble tells RBR-TVBR: “We're thrilled to have reached a compromise which moves the power increase forward and view it as a critical milestone in the HD Radio rollout. It shows the industry's ability to come together and achieve consensus on key issues and their commitment to move HD Radio technology forward.”
 
The agreement proposes that the Commission authorize a blanket 6 dB increase for all commercial and non-commercial radio stations’ digital power from the current level of -20 dBc to a power level of -14 dBc; this is four times the current power level. NPR and iBiquity consulted with a broad spectrum of commercial and noncommercial stations over the last few weeks, and identified several conditions and criteria to manage the power increase process. 

These conditions were informed by NPR Labs recent field research, “Advanced IBOC Coverage and Compatibility Study,” filed with the Commission earlier this week.  Conditions of the blanket increase included commitment by iBiquity and NPR to additional enhancements to the HD Radio™ system. The development work of the two organizations will focus on single frequency networks to fill gaps in digital coverage, asymmetrical digital sidebands to reduce the potential for digital interference to short spaced first adjacent analog stations, and low bitrate codecs and conditional access crucial to moving radio reading services into the mainstream of digital radio broadcasting.

Notably, the two organizations offered an approach to additional power increases beyond a 6 dB increase, depending on spacing criteria and conditions that limit harmful interference, and initial models suggest most stations will be able to exceed 6 dB. 

Mike Starling, Executive Director of NPR Labs, said “We are optimistic about the future of HD Radio broadcasting, and eager to continue to work with iBiquity on the developments that will make this power increase work to everyone’s advantage – stations, listeners, and receiver makers.” 

Commenting on announcement, NAB EVP Dennis Wharton said that NAB is encouraged by the consensus: "We urge the FCC to move quickly and allow stations to operate at increased power according to the criteria in the agreement. This will result in greatly improved indoor reception for digital signals, including multicast signals, and pave the way for greater service reliability using portable HD Radio devices."

"I am thrilled that a workable and efficacious compromise has been agreed to on this extremely important and controversial issue," said Milford Smith, Vice President of Radio Engineering at Greater Media. "Replication of analogue coverage by the new, digital service is absolutely critical to the continued successful roll out of HD Radio technology." 

iBiquity and NPR encouraged the Commission to act on unresolved complaints in cases in which interference is shown to cause a problem.

The agreement also proposes a series of steps drawn from the current AM rules for interference to be applied to qualifying and limiting harmful interference with analog at the 6 dB increase level (-14 dBc). These steps would remediate harmful interference from any stations increasing power above the existing -20 dBc power level. 

RBR-TVBR observation: We spoke with Struble in early August about also using asymmetrical IBOC power levels, where for some markets the power would be higher on one channel side of the analog signal and lower on the other. This should also be taken into consideration by the FCC in mitigating interference complaints with these higher power levels, should they be approved. Struble confirmed that the current HD receivers will work with asymmetrical power levels should it be implemented at some stations:

Bob Struble audio interview - part I
Bob Struble audio interview - part II