Charles W. Rhodes

Last month, this column covered DTV-DTV interference from one and two undesired signals. In this issue, we will address the matter of triplets of undesired DTV signals.

Had the FCC been able to anticipate this problem of receiver-generated IM3 (noise) in ���vacant channels,” perhaps it could have established minimum performance standards for consumer DTV receivers.

By the time you read this, the FCC is expected to propose a set of rules by which unlicensed devices will be allowed to share TV Channels 2–51.

Since my article in the Oct. 19, 2005 issue of TV Technology, ("Developing a 24/7 Digital EAS System"), some real progress has been made by the FCC in the matter of the Emergency Alert System.

I have recently written about the hot topic of sharing broadcast spectrum with unlicensed devices.

Ghosts of DTV signals could easily be seen on analog TV screens, but with DTV, they are invisible on the TV screen.

The average field strength of a SFN would have to decrease to permit all incumbent broadcasters to continue to with their very own channel.

There are no minimum performance specs in the FCC rules, and in fact, the FCC does not have authority to set them.

Lagging echoes are more the serious problem

The FCC Laboratory report on the interference rejection capabilities of modern DTV receivers dated March 31, brought to my attention the fact that many viewers live in relatively weak signal areas.

The saga of the FCC Laboratories Report, “Interference Rejection Thresholds of Consumer Digital Television Receivers Available in 2005 and 2006” continues.

In its recent Report and Order, the FCC revealed 11 scenarios under consideration for a 600 MHz Band Plan following the spectrum auctions.

The FCC has defined how close to, but outside of the predicted noise-limited perimeter of a station, a DTVB can be operated on the same channel as a DTV station in that community.