Your browser is out-of-date!

Update your browser to view this website correctly. Update my browser now


NRSC Updates RF Mask Compliance Guidelines

RBDS group hopes to simplify implementation; iBiquity studies AM analog display improvements

The Las Vegas Hilton ballroom where the National Radio Systems Committee members congregated this weekend was a happening place.

Members added an FM quality measurement technique to the IBOC measurement guidelines for RF mask compliance for both AMs and FMs. Also, members are still working on RBDS projects and heard an update from iBiquity of a digital data rate project for analog AMs.

The measurement guideline update, a new standardized method for determining the transmission quality of an FM IBOC signal — Modulation Error Ratio — has been in the works for some time and the guidelines will continue to be updated as the IBOC technology progresses, NRSC Chairman Milford Smith told me after the meeting. The gist is MER measurement can help a station measure errors present in the data.

The guidelines provide concrete suggestions for how to analyze FM IBOC transmission, including what settings to use on different test equipment to make sure stations are all measuring the performance of their IBOC systems in the same way.

RBDS Subcommittee Chairman Barry Thomas chimed in: “This is a document you can hand someone and say, ‘Here’s what you do. Go out and test these stations.’”

The guidelines will be on the NRSC Web site in about two weeks after a procedural review.

Meanwhile, the RBDS Subcommittee is working on implementation guidelines to make station procedures simple and the user experience more consistent. Right now, receiver manufacturers implement the RBDS display in several ways. “We’re trying to reach out to broadcasters to let us know how they’re using it,” said Thomas. “Once you see what everybody’s doing, then it’s easier to develop a guideline.”

The hope is receiver manufacturers would then see how stations are using RBDS and how they want to use it so manufacturers will standardize the displays, which, in turn, would lead to more consistent consumer use.

And finally, iBiquity provided NRSC members with an update on an NAB FASTROAD-funded Project to develop a method for transmitting digital data with an analog AM signal, so that new HD Radio receivers can have a snazzy analog AM display, similar to what FMs have.

Smith told me that many details, such as the ideal bit rate, are still being discussed. iBiquity’s Jeff Detweiler said during a Sunday session the company has studied six design options, and is narrowing in on two for further study.

iBiquity hopes to have a report out on the concept by the fall NAB Radio Show.