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FCC To Open Up Vacant TV Airwaves For Broadband
crimeandpunishment writes "Get ready for 'super Wi-Fi.' If the FCC works out the last details of new spectrum rules, they'll open up the so-called 'white spaces'... the vacant airwaves between broadcast TV channels ... for wireless broadband connections. If the plan goes through, it will lead to Wi-Fi with longer range and stronger power. The stumbling blocks have included concerns about interference with TV signals and wireless microphones, but the FCC plans to vote next week on rules meant to resolve those issues."
Dear Slashdot,
I'm killing myself. My wife left me today.
Thank god. I'm personally tired of all the useless comments from that guy named "Anonymous Coward" anyway.
Tequila: It's not just for breakfast anymore!
I'm glad the FCC is leaning toward unlicensed use of the spectrum instead of selling it to some M$ like concern. I hope they put enough common sense regulation in place to allow the spectrum to be used without mutual interference with itself. Digital TV is somewhat more imune to interference than analog, but the new wifi devices do need to be self configurable to avoid assigned TV channels.
...to whom will we have to fork over the hefty monthly charges to use our "public" airwaves?
This space available.
>>>Digital TV is somewhat more imune to interference than analog
False. I've switched to DTV and it's amazing what will block it. I turned on a vacuum cleaner and said goodbye to 50-mile distant channel 6 disappeared. In the old analog world it would have simple added some "fuzz" on the screen but still watchable. And when we have storms, we lose the DTV where the old analog signal never disappeared. DTV can no longer be relied upon for areas with bad weather (think Tornado Alley from Texas to Minnesota) (or Hurricane Alley from Florida to Maryland).
And what open frequencies?
No joking but here is a list of all the channels currently in used along the Mid-Atlantic (near New Jersey). Where the hell does the FCC think Wifi devices are supposed to operate? I suspect what will actually happen is the teen girl next door will turn-on her device directly over top the Baltimore or Philadelphia station I'm trying to watch and make it disappear.
6
7
8
9
10
11
12
13
14-21 (reserved for police in NY City and state)
24
26
27
28
29
31
32
33
35 (reserved for radioastronomy)
37
39
41
43
44
45
48
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50
Plus dozens of low-power "neighborhood" transmitters that serve local communities.
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
Data still takes bandwidth, and we can't get more than 19.39 Mbps into a single 6 MHz channel (at least with 8VSB). So until we switch to another modulation scheme (and obsolete all the new ATSC equipment) we're stuck at 19.39 Mbps. We can pack more program streams into the transport stream but with MPEG2 which is currently mandated we can only do that by reducing the quality of existing streams. (Not the programming quality, that's an entirely different subject.) MPEG4 can help significantly but that would once again obsolete a bunch of fairly new equipment.
Two points need to be made:
1. Most of the time channels could share a single transport stream, but it will be quite difficult to get competing media corps to do that.
2. The UHF spectrum is ideally suited to the current business structure of the media corps and the wide spread use of receivers (TVs) means a lock-in on the UHF band for years to come.
In a decade or so we can probably implement MPEG4 (or whatever standard has been established at that point) for over-the-air broadcasts, but right now a bunch of people just bought new TVs and want them to last for 5 - 10 years. Moving to an entirely IP based broadcast methodology would require a number of safe guards in the end-to-end distribution to ensure that people who rely on TV broadcasts for emergency information will not lose information due to a DOS.
Take this with a grain of salt. I'm in the broadcast equipment industry and keeping thing status quo does make my life easier.
Hey good lookin, we'll be back to pick you up later!
The stumbling blocks have included concerns about interference with TV signals and wireless microphones, but the FCC plans to vote next week on rules meant to resolve those issues.
Why can't those politicians vote on something more useful, like repealing the law of gravity, or laws of thermodynamics? I'm sure its likely to be equally successful.
What are you talking about? "Rules to resolve issues" doesn't sound anything like anyone implying magical physics-breaking measures, it sounds like regulations on exact frequency and signal-strength, which there would obviously be anyway. Sensationalist much?
>>>Imo, TV signals are a waste of bandwidth...
Not really. They stream ~20 Mbit/s of video to approximately 0.5 million homes per city/market. That's over 6000 gigabytes of television/news per home, or 3,000,000 terabytes total. Show me any internet or cellphone that can do the same, and at $0.00 cost per year. You can't. - (Imo, only a fool pays for watching Supernatural or CSI or whatever else you enjoy, when it's available for free.)
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
There are no "buffer" bands, analog TV used 2 carriers in the 6MHz channel and you could find some free space as long as you didn't mind the interference with either the audio or video. DTV uses all of the 6 MHz with almost no channel edge gap and is spread spectrum like wifi so there are no gaps to sneak into. In the major metropolitan areas the reality is there will be NO free channels for TVBDs. Which means that a lagre percentage of the US population will gain no benefit form the TVBD devices because they will have no channels to use them on.
Phased array antennas can detect the 3D position of the source of a signal, distinguished from other transmitter locations sending on the same frequency. It's how humans with eyes can tell there's two blades of grass in front of them, not just "it's green out".
A phased array could make frequency segregation unnecessary, and vastly increase bandwidth without interference. By doing so, it would completely destroy the entire basis of the FCC, except as certification that phased array devices work properly.
How far along has phased array tech come for either stationary devices like base stations, relocatable ones like notebooks, or low power ones like phones? Products with these features are long overdue, and mobile telecom will be revolutionized by them.
--
make install -not war
Just tell them to make sure they waterproof it first.
And you have to either throw away HD, or switch to MPEG-4 (obseleting receivers, etc). A single 19Mpbs transport stream can't hold two decent-quality 720p MPEG-2 channels, so either you go with 480p or you overcompress to the point that it looks worse than 480p.
This is tentative step toward cognitive radio.
They are reusing channels that are allocated for television but not actually in use for that purpose in particular areas. TV is pretty easy to work with. There are few, powerful, transmitters and they transmit all the time. In TFA, some even suggested using GPS and a database to figure out which channels are available.
That's pretty crude. In a fully cognitive radio system, the device listens for transmitters on a range of frequencies. If it finds open spectrum, it sets up shop. This can be tricky as it has to distinguish vacant channels from ones that are occupied but with a weak signal. Also, the owner could simply be off line. When the licensed transmitter comes back, the cognitive radios must vacate.
Still, the potential is huge. In principle, *all* licensed bands could be reused by cognitive radios. At any given time and space, a great deal of valuable spectrum is simply wasted. The licensee, if they even exist in this area, isn't using the channel and no one else is allowed. Cognitive radio would open up those regions to the rest of us.