New Rules From the FCC Open Up New Access To Wi-Fi

CarlottaHapsburg writes: White space — unused channels in the VHF and UHF spectrum — is already part of daily life, from old telephones to going online at your coffee shop or plugging in baby monitors. The time has come to 'permit unlicensed fixed and personal/portable white space devices and unlicensed wireless microphones to use channels in the 600 MHz and television broadcast bands,' according to the FCC. One of the ramifications is that Wi-Fi could now blanket urban areas, as well as bringing it to rural areas and machine-to-machine technology. Rice University has tested a super Wi-Fi network linked by next-generation TV or smart remotes. Carriers are sure to be unhappy about this, but consumers will have the benefit of a newly open web.

Comments

I'll Wager

[Anonymous Coward]

$5 says that the 600MHz spectrum gets sold to cell companies.

You plebs don't need a $50 WiFi router that can reach a mile away.

Re:I'll Wager

[Areyoukiddingme]

$5 says that the 600MHz spectrum gets sold to cell companies.

You plebs don't need a $50 WiFi router that can reach a mile away.

If it was for sale, then you'd get your $5. But it's not. "Whitespace" spectrum is unlicensed, limited use of existing licensed spectrum which will not change hands. This is what Google has been after since the 700 MHz auction in 2008. The existing licensed users (OTA TV stations) stay in place, and maintain priority. But they're not using all of the spectrum in every major market, and there are very few licensed users in rural areas. All of that empty spectrum (minus guard bands around the licensed users) can be used ad hoc by transmitters that obey the power caps.

This ruling makes available TV channels 2 through 51 for the general public, as long as there is no incumbent licensed user. In practice, that means rural users could get lots of bandwidth. City users in the most crowded television markets get almost nothing.

Bandwidth?

[Rob Lister]

At 400-700Mhz what kind of bandwidth can they accommodate?

Since the article tells us neither the number of channels they'll open or the width of those channels, I'm not sure that's knowable yet.
I think the formula is 2.5bits/s/hz/cell under perfect conditions.

Re:Bandwidth?

[Mal-2]

A 20 MHz channel is just as useful at 400 MHz as it is at 2.45 GHz or 5 GHz, or more so because it has better penetrating capability. The obvious problem (which I assume is what you were getting at) is that there aren't as many 20 MHz slices to go around between, say, 400 and 460 MHz as there are between 4 and 4.6 GHz. Antennas also get smaller with increasing frequency (decreasing wavelength). When is the last time you actually saw the antenna on your phone, unless you dismantled it to find it? In the UHF band, you're going to have manageable but still visible antennas, like you did back in the old analog cell days.

I suspect the paucity of channels, combined with the higher degree of interference because the signal carries better, will prove crippling for low-UHF WiFi. It might still be quite useful in fixed installations with directional antennas, such as connecting houses to a central tower.

Re: Bandwidth?

[drinkypoo]

I would far prefer a reliable 13Mbps that covers a while multi-acre lot than 54Mbps that I can't even use at one end of my house.

It doesn't matter because if they open up a new band with more range then you'll just have more stations to compete with because you can fight for spectrum with people who are farther away.

Re: Bandwidth?

[hawkeyeMI]

I run a small rural WISP. Wisps need more spectrum by the hundreds of megahertz of spectrum. Nobody's very excited about these small openings of spectrum, take it from someone who is actively trying to blanket his area in WiFi.

Re: Bandwidth?

[Ol Olsoc]

I would far prefer a reliable 13Mbps that covers a while multi-acre lot than 54Mbps that I can't even use at one end of my house.

It doesn't matter because if they open up a new band with more range then you'll just have more stations to compete with because you can fight for spectrum with people who are farther away.

You are correct. While in principle this is a good idea, RF does not always act like most people think it will act.

Any system that has longer range actually means less people can use it, and then there is that propagation - great fun for experimenters and Amateur radio operators, when a thermal inversion or electromagnetic solar activity makes for much longer than normal contact distances. Not so much fun for digital data.

That 2.4 GHz neighborhood is actually about the best compromise for range, and immunity from weird propagation we can get.

The UHF white space utilization isn't exactly a bad idea, but I smell another BPL fiasco could be made from it.

BPL, was that batshit crazy idea of sending DSL speed internet to consumers by way of their power lines.

It ultimately failed because of what the boys down at the shop call a SFI (Stupid Fsckin' Idea). The wires acted just like an antenna, and spewed radio interference all over the place, the signal could be interrupted by kids with CB radios, and the best part was that the signal going into your house couldn't survive the trip through your power pole transformer, so they put a little bypass device to "inject" the digital signal, which was carried on the High Voltage lines, not your puny 120 or 240 lines - better hope those injectors always fail open!

If this turns out to be another bureaucratic faith based technology implementation - should be fun.

initial issues are going to be getting any efficiency out of the antennas - they will be bigger, and that longer range issue will be an issue as well. Proponents need to take a look at the UHF antennas on some houses in the country to get an idea.

Re:Bandwidth?

[Lumpy]

That is already been kicked in the nuts.

Back in the early 2000's I helped set up and run a community Wifi. Comcast helped pass laws making what we were doing illegal and within 5 years we had to shut down. It was actually very easy as every customer that paid for full time access was another node for the other customers. As a paying member you got full speed access, and the wifi you broadcast for free was very throttled and had bottom level priority. WE used all off the shelf parts using DISH network dishes mounted upside down and at the end a linksys router in a waterproof box mounted on your roof pointing back to the nearest hop.

we had to disassemble it as it was now illegal as we were creating a service without paying a franchise license. We asked to buy a franchise license and were told, "there is only one available and it's already sold"

You will not see community wireless internet spring up not unless city hall is burned down and the mayor and all the council are in stockades on the lawn being pelted with rotten food.

Curious, how did they do that?

[140Mandak262Jamuna]

V signals are broadcast as normal and the WATCH system actively monitors whenever a nearby TV is tuned to a channel to avoid interfering with reception

The TV receiver is a passive device, right. How would they know there is a nearby TV that is tuned to that particular channel? Could they detect a simple VCR or DTR that simply records the over the air signal for the stingy time shifters who balk at paying the monthly fees to TiVO? Or messing up such penny pinching a feature and not a bug?

Re:Curious, how did they do that?

[currently_awake]

It is very easy to detect a receiver. In a superhetrodyne receiver you generate an RF signal to mix with the incoming signal, and that signal can be detected.

Re:Curious, how did they do that?

[BitZtream]

The TV receiver is a passive device, right.

No, not even a little bit.

It does not intentionally transmit signals. It is however filled with RF circuits designed to decode the incoming signal, the laws of physics ensure that these circuits also produce signals of their own. Ideally, these are shielded. Realistically, the shields aren't that useful and the sidebands that are being produced aren't being used by other nearby things that will be overwhelmed by the extra RF output of the TV.

FCC laws prohibit TVs from transmitting ... but the laws of nature still seem to overrule the FCC.

This applies to TV tuners as well as TiVo, you're car radio, cell phone or anything else that receives signals. Theres an oscillator in it thats helping to decode the signals, and at the same time, transmitting some things as a side effect. Even your computer monitor is transmitting signals and thats why you can actually read data from monitors you can't even see with the right equipment.

Doesn't work over very much range, but its pretty simple to detect and decode within short ranges (for varying definitions of short range)

Hopefully CONSUMER gear

[The Cisco Kid]

will be made using these bands so that individuals can set up their OWN access points to connect to from their OWN client devices, rather than making the "head end" side so expensive only big businesses can afford to buy and run them.

Unlike how WiMax went down.