In Florida, a Cell Phone Network With No Need For a Spectrum License

holy_calamity writes "Technology Review reports on a cell phone network in Fort Lauderdale, Florida, like no other. Instead of paying to reserve a section of wireless spectrum its owner, xG Technology, uses cognitive radios that steer signals through the unlicensed 900MHz band more normally used by cordless phones and baby monitors. The radios in both handset and base station scan for gaps left by other devices in that band and make dynamic connections that constantly hop frequencies to ensure a good link. The network is designed to show off the tech, which the company says could be used in conventional cellphones to access extra spectrum or white spaces devices."

Comments

So what's the range

[drachenstern]

and does it use a lot of "femto-cell" style towers? It would seemingly have to. Meaning, how well would it work in a car?

Re:So what's the range

[jonbryce]

900Mhz is the most popular GSM band in Europe and most of the rest of the world. My mobile operator uses it, and it works very well in my car. I guess that means it would be illegal to use this phone in most parts of the world.

Re:So what's the range

[zn0k]

The 900Mhz ISM band is free to use in region 2 (the Americas, Greenland, and part of the Pacific Islands).

It isn't going to work

[Anonymous Coward]

It's never going to work in the long term. I work for a wireless ISP, and our 900 mhz band is getting killed by utility/electriticy companies rolling out things like smart electric meters that exist in every home and do the same thing: hunt for the least noisy band and transmit. We've seen noise floors in the -40s straight across the spectrum on our worse days. We can't beat the noise more than a couple of miles from a cell tower using fixed, directional antennas. What makes them think they can beat it with tiny, handheld devices?

Re:It isn't going to work

[snowraver1]

I would mod you Informative, and I have the points, but I'll be damned if I can find the apply moderation button to make it take effect.
br>Also, why am I now being forced to preview? Maybe I like making errors.

Re:It isn't going to work

[maxume]

They changed the name of a pref from 'Use Classic' to 'Dynamic Discussion', defaulted it to 'yes' and made it so that it can only be accessed (as far as I have found) from the prefs that pop up with the button on the bottom of the comments pages.

Re:It isn't going to work

[MightyMartian]

The ISP I worked for (and managed the network operations of) mucked around with 900mhz band proprietary WiFi and it was, for the most part, a total disaster. The worst came when the guy whose apartment was immediately below our antenna went out and got some sort of 900mhz cordless phone that just splattered horribly over that area of spectrum, taking everything down with it. My boss literally went out and bought the guy a 2.4ghz phone just to stop it. Then the pager tower near one of our other antennas went crazy and started spewing forth over that bit of spectrum too.

We were told by the supplier that their equipment could pick the holes in the 900mhz unlicensed band, but so far as I could tell, anything beyond fairly mild interference just made the whole system highly unreliable. Hell, the last 900mhz cordless phone I bought when we were stilling living in an apartment was constantly picking up other phone calls.

I didn't know dick about radio at the time, but asked my boss why weren't going with 802.11b (which had just become available not to long before, and was up in the 2.4ghz range and had a growing number of WiFi devices that could talk to it, meaning we didn't have to rent out custom WiFi units to our customers). He liked the proprietary stuff because it was more secure (true enough, from an obscurity point of view, though I don't think it was encrypted) and because he wasn't relying on the 802.11 access control methods (though he had no problem with a Radius server for our dialups).

The 900mhz bands are just to bloody dirty and too congested.

Re:It isn't going to work

[Pharmboy]

Also, why am I now being forced to preview? Maybe I like making errors.

Slashdot wasn't losing users at a fast enough rate, so this is part of a new program to piss those of us off that have been here for many years, and get us to finally leave forever. It is about to work.

Re:It isn't going to work

[Pharmboy]

Thank you. Finally restored the old, crappy, but understood format. I wish Slashdot would spend less time writing code, and more time reading and editing articles if they really want to improve the site. I'm just hanging by a thread as it is.

From the article . . .

[commodore64_love]

the system could augment emerging networks that operate in the unlicensed "white spaces" recently freed up by the end of analog TV broadcasts

The only channels "freed up" when US NTSC ended was 52-69 and they've already been designated for Cellular and Emergency Radio usage. These gadgets are verboten from broadcasting in that area.

A recent study by University of California-Berkeley academics revealed how the density of TV stations in metropolitan areas could reduce the availability of white spaces in such areas.

That's true. The "whitespace" idea only works in rural regions, not heavily-populated areas like the North, northeast, or mid-atlantic which use every channel from 1-51 (including the FM band).

Validity Questioned

[philipborlin]

This article questions the validity of the company.

Ricochet did this a decade ago

[Animats]

Ricochet did this in the 900MHz band using spread spectrum a decade ago, for wireless Internet access. They put up little nodes on street light poles, using a deal where the municipality got free data access. It worked fine, but only delivered dial-up speeds, so it was overrun by DSL and cable. Even back then, getting around narrowband interference was no big deal.