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by runeks 4281 days ago
I think it may have a lot to do with regulation.

I've been looking around, to see whether I could find information on the total bandwidth of the DVB-T(2) spectrum for some country, but I couldn't.

I want to know because I'm wondering if, perhaps, the technical abilities are there, but we can't use them because only a select, small set of frequencies are allowed for data transfer.

I'm still not sure whether that's the case though.
2 comments
foobarqux 4281 days ago
It has nothing to do with regulation, it has to do with physics. Wireless is not nearly as good a communication channel as fiber or cable. Intuitively this is because of interference with other signals, reflections and obstructions, all of which are continuously changing.
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wtallis 4281 days ago
It's also due to the fact that there's only a few GHz of spectrum in which cheap equipment can broadcast a powerful enough signal to go any useful distance. WiFi operating in 2.4GHz and 5.8GHz are tricky but not impossible to use for anything longer-range than a single building. Much higher frequency, and you have to use pretty powerful transmitters and well-aimed highly directional antennas. Current tech allows for a few bits/s/Hz, so there's only a few gbit/s of bandwidth to be allocated between all long-range communication uses. If you want to offer gigabit speeds to households over wireless, you have to deploy a mesh network that's so dense it would be cheaper to just lay fiber.
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Retric 4280 days ago
You can use directional point to point links to give you basically unlimited bandwidth. The issue with cellphone bandwidth is simply the number of cell towers being kept to low. There are some limits on how close you can space towers but you could for example use one tower per city block.

PS: This is why you can have temperary cell towers for events. http://en.m.wikipedia.org/wiki/Cell_on_wheels

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e12e 4281 days ago
Apparrently, DVB-T(2) is pretty close to the maximum allowed [according to] Shannon -- so it really just depends on what frequencies are used (and coding details). It is a frequency that is well suited for broadcast ("push") -- so not sure if de-regulating it for general send-receive is such a good idea (see sibling comments). Anyway, did you see:

http://www.satbroadcasts.com/DVB-T_Bitrate_Calculator.html

And:

http://en.wikipedia.org/wiki/DVB-T2#Technical_details

?

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