With the date certain set for Feb. 17, 2009, to shut off analog TV transmission and figures from the Consumer Electronics Association showing that consumers are now buying more DTV than analog sets, it would seem that nothing could derail the over-the-air digital television, and along with it high definition.
Not so, according to David Donovan, president of the Association for Maximum Service Television. There are legislative proposals that would permit millions of unlicensed devices into the broadcast television band in the so-called white spaces. Permitting millions of these devices in the band will create interference to millions of new digital television sets and the new government-funded digital to analog converter boxes. This is a direct and immediate threat to a successful digital transition.
There is also a more immediate problem on the horizon. Qualcomm’s new MediaFLO mobile video service poses a serious threat to analog and digital broadcasters operating on Channels 54, 55 and 56, he said, because the company is seeking a change to commission rules that would allow the new service to create 2 percent more interference to those channels than envisioned at the time it acquired Channel 55.
While on the surface the situation may not appear to threaten all broadcasters, it raises a serious public policy question about whether a subscription service should be allowed to interfere with free over-the-air TV that millions continue to rely upon for news, information and emergency warnings, said Donovan.
Given the broader implications, HD Technology Update thought it was time to touch base with Donovan about the MediaFLO interference issue.
HDTU: How did the Qualcomm MediaFLO interference issue develop?
David Donovan: Let’s start with the proposition that Qualcomm — when it acquired Channel 55 — did so under specific conditions. The conditions were in the FCC rules that effectively said there should be no new interference to existing TV broadcasters. The commission said, “You can set it up, and operate, but it can’t interfere with broadcasters.”
Qualcomm acquired Channel 55 with that understanding. Several years later Qualcomm filed with the FCC saying, “We think the existing rules are too stringent, and we should be permitted to have a waiver which would allow us to put 2 percent more interference across the entire 700MHz band.”
The second thing is Qualcomm wants to use the OET69 measuring technique, which was a measure designed to analyze interference from big towers in the weak signal condition at the outer edge of a station’s contour. OET69, by itself, was never designed for, nor is it proper for, analyzing interference emanating from multiple towers operating on a channel within another station’s contour. In these cases the interference is not at the edge of a station’s service area, but it will be found in heavily populated regions. We believe that Qualcomm’s use of OET 69 is incorrect and may underestimate the levels of interference caused by the MediaFLO system. Third, Qualcomm asked for an expedited process at the FCC, which in our view flips the burden and puts the burden on broadcasters that MediaFLO won’t interfere with broadcasters. And all of this happened in an incredibly short time.
HDTU: Where does the issue stand today?
DD: Both parties are trying to make their cases. I don’t know when the FCC will make a decision. I know Qualcomm thinks it’s on a tight clock. But our fundamental concern is interference to broadcasters and to DTV operating in that band.
We are concerned about interference to adjacent Channels 54 and 56 and co-channel interference to Channel 55.
What we are looking at here to some degree is unjust enrichment. Qualcomm bought the spectrum under certain rules, and now it wants them changed. Two percent interference can affect a large number of people. For example, in Los Angeles you may be talking about hundreds of thousands of viewers. And you cannot casually dismiss that these consumers should be denied free over-the-air television service.
Moreover for DTV, the commission established rules requiring stations to power up their DTV stations. These rules are designed to help drive the DTV transition by reaching everyone with digital television service. If Qualcomm got its way, those efforts to deliver DTV would be for naught because you’d lose 2 percent of DTV viewership.
There is a fundamental policy question at stake. Will the commission permit an involuntary loss of universal, free over-the-air viewing in order to facilitate the development of a subscription based-based video clipping service you can see over your cell phone? The TV viewers receiving interference will be disenfranchised, losing access to news, public affairs and important emergency information.
HDTU: In MSTV’s correspondence with the commission, you’ve made the point that to allow MediaFLO to produce 2 percent greater interference would disproportionately affect Hispanic television viewers. Why?
DD: There are a couple of issues here. Most of the data on TV usage is that Hispanic populations rely more heavily on over the air as opposed to cable or satellite. So therefore, any interference makes them more vulnerable to loss of important information.
Moreover, the nature of the architecture that will be rolled out by Qualcomm may have a disproportionate impact on these populations. For example, if it were approved, you could set up a system that causes 2 percent interference to a TV station’s coverage population. But Qualcomm intends to use multiple smaller towers in some markets. Let’s assume that one of the towers Qualcomm is using is located near an area with a significant Hispanic population. Even though it may be 2 percent overall, the impact on the Hispanic population could be much higher. It is all a function of where Qualcomm is placing the towers. At this point we do not know where these towers will be located.
HDTU: What do you want the commission to keep in mind as it makes its decision?
DD: The commission and the government have an obligation to ensure that American consumers retain access to free-over-the-air TV. And that should be protected. We are at a critical time in the DTV transition. We should do everything in our power to make sure consumers accept DTV. If this is the government’s goal, it makes no sense to generate increased interference to new DTV stations.
Qualcomm entered the process knowing the rules, and they shouldn’t be allowed to change the rules in midstream.
From an engineering standpoint, it is extremely important that the correct methodology be used to analyze interference from a multiple transmitter-tower architecture that is placed within a station’s contour.
Personally, it seems to me that since Qualcomm is trying to interfere with broadcasters, the burden to develop the correct methodology is on them. However, we are working on a way to measure interference from these kinds of systems.
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