White spaces and black hearts
Those pushing white-space proposals, including Google's Larry Page, need some lessons in real-world RF interference, and the industry should put white-spaces plans on hold until we see how badly the digital-TV rollout hurts broadcast television.
By Paul Rako, Technical Editor -- EDN, October 16, 2008
Google co-founder Larry Page is still pushing radio white-space proposals (Reference 1). White space refers to the unused television channels in a region, along with the spectrum-guardband buffer between channels. Page makes the absurd claim that small devices, such as his new G1 phone, cannot possibly cause white-space interference. He calls recent tests on white space “rigged” and “despicable” because the testers conducted research on wireless-microphone-interference avoidance while using nearby TV frequencies.
I remember the days when Google's mantra was “Do no evil.” I suspect that Page, referring to Google's “Free the Airwaves” publicity campaign, thinks he is doing no evil—perhaps even doing good—by helping the people. I agree that the telecommunications industry has a history of despicable behavior. And, although the industry needs to address the high costs of cell-phone plans and the associated poor quality and lousy service, Page is wrong to call broadcasters despicable for fighting something that almost certainly causes TV interference.
Some analog engineer should explain to Page that the size of a device has nothing to do with interference. A few watts from a cell phone are enough to interfere with the microvolt TV signals your tuner is trying to pick up. The real problem lies with the base stations. Unless the White Spaces Coalition Wireless Innovation Alliance proposes to make a device-to-device mesh network, it will need base stations, just as any other cell-radio system needs base stations. And, unless the coalition proposes to put those base stations into satellites, the base stations will be near a bunch of TV receivers. A lot of neat charts show that radio transmissions occupy only a small slice of guardband, but RF artifacts, including side-lobe and multipath effects—inherent in the real-world transmission of radio waves—will occur with white-space broadcasts, too.
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It is madness to propose the introduction of any potentially interfering devices until after the rollout of digital TV next February. My experience is that digital is not all that it is cracked up to be. A plane landing nearby or someone using 802.11 or unlicensed devices seems to cause problems with some digital TV broadcasts. Other digital broadcasters' signals are so weak that the broadcasts keep dropping out and become unwatchable. Analog transmissions from the same broadcaster may come in “snowy,” but the audio is crystal-clear and you can still watch the broadcast. Like most other things of a digital nature, it is perfect when it works, but let's wait until we see how delicate these digital-TV transmissions are before we put even more interfering devices into the same frequency bands.
Page may want to consider the social-class component of all these proposals. Millions of people in the United States cannot afford cable or satellite TV. They won't be buying a smartphone, and they won't be using Google to find coffee shops selling lattes with just the right amount of foam. These people are living from paycheck to paycheck, and the one respite they get after a day's work may be watching free broadcast television. Just because Google and the cell-phone companies have better lobbyists and more money than the broadcasting industry is no reason to abuse these people.
The Federal Communications Commission has become less concerned about interference and more concerned about money. It has gone from being a technical organization to being a political one. With modern-day fiscal disasters, such as the war in Iraq and the collapse of the housing market, the FCC is under even more pressure to add to the revenue stream. Nevertheless, the industry should put white-space transmissions on hold until we see how badly the digital-TV rollout hurts broadcast television. The cell-phone companies engineered one rip-off of US citizens with digital TV. Let's not allow the Web-search and computer companies to pull off another one.
Contact me at paulrako@edn.com.
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Thank you for this editorial. The last thing the OTA
Broadcast industry needs is licensed interference. The
8VSB is not living up to its expectations, and stations
cannot afford to lose any more viewership to cable and
satellite.
The FCC is constantly being jerked around by special
interests with products to sell. EAS, HD radio,
the 2ghz re-allocation, the 220mhz re-allocation, the
BPL techlogy, and the ATSC itself are all examples.
The list goes on and on....
Ralph Carmichael - 2008-7-11 13:32:00 PST -
Thank you for the forceful words in defense of the public good against
the powers of Google. I have "no dog in the fight" over the use of
spectrum, and I don't lean one way or another on the issue.
I enjoyed reading your piece, even without a person interest in the
outcome, because of the passion in your position. Your words are
heartfelt, and the sincerity of your arguments makes the story compelling.
I wish there were more of that to be found in technical and trade journals.
Thanks for taking a stand.
John Goodman - 2008-24-10 14:48:00 PDT -
Come on Paul...
Do you really believe what you said about the
"Social-class component"?
Really...
In another part of my life, I have spent years in emergency services, both paid and volunteer. Due to
misuse and abuse of ambulance services, and the
normal trials and tribulations of life, I have been in thousands of low income residences. Just those people
you mention, living from paycheck to paycheck, or more often some sort of government program check.
I would venture that 90% of those had cable or satelite TV.
At least 90%.
Free broadcast? Only in a few markets can you see Springer for free!
Do you want to help that social group? Volunteer some time in literacy lessons. Become a Big Brother. Maybe they will let you watch HBO at their house.
Blake Bowers - 2008-23-10 06:39:00 PDT -
I heartily agree, but not for all of the same reasons. As a part-time sound engineer for local theatre groups and high school choirs, I know that enactment of the current proposals will eliminate our ability to use wireless microphones and systems. Unfortunately, we, and by extension the entire amateur and pro audio communities do not have near the money or lobbying clout required to compete with Google and their cohorts. I read an editorial in which was stated that Congress will probably be happy to support this revenue-generating proposal until those broadband devices start interfering with their political speeches.
J. Mizener - 2008-22-10 13:19:00 PDT -
I JUST READ YOUR EDITORIAL ABOUT DIGITAL TV AND AGREE with you about the problems coming up. I have a summer home in Northern Michigan(north of Menominee) and receive Green Bay tv regularly usnig analog. A couple of stations are not too good during the day, but usually viewable during the evening. I decided to buy a digital converter from Best Buy in June and also one from Target at the same time frame. When I tried the first one(INsignia) I received nothing. The Target one worked OK but I still watched analog as I could get it all the time. I could only get one channel(2) during the day with 38 sometimes. None of hte other channels worked during the day. Later I bought a Radio Shack and also a Channel Master converter to see if they were any better. No luck. I do not know which channels are broadcasting in digital format yet up there so I may get more after Feb, but who knows.
I have found that whoever designed the converter boxes does not understand people in the country as they do channel searching for signals and only the Radio Shack converter allows you to go to a channel which the converter box did not scan in during set-up. Really stupid as you cannot add the channel to the existing ones for test purposes.
Hopefully your editorial will help to make people aware of the stupidity of those in power who are just money hungry.
Ed Downs
P.S. I tried to e-mail you and the address bounced
Edward Downs - 2008-22-10 12:24:00 PDT
