
How new 'white space' rules could lead to an urban super-Wi-Fi - doener
http://www.computerworld.com/article/2970867/wireless-networking/how-new-white-space-rules-could-lead-to-an-urban-super-wi-fi.html
======
superuser2
Dying inside. This spectrum is essential for wireless microphones. The big
corporate rental houses can buy new inventory, but many of the operators are
churches, schools, and nonprofit theaters who were able to purchase equipment
only with grants, serious fundraising, and years of savings.

You're robbing every nonprofit with a performance space of potentially $30k+
of essential equipment that is now worthless.

I work at a campus venue with around $20k of Shure ULX in this frequency band.
We just went through a round of budget cuts and if we have to stop operating
this equipment, it will probably never be replaced. This means students can't
do amplified musicals anymore.

Even if it is for the greater good, please understand who you're fucking over
here before you cheer it on.

~~~
Raphael
So there will be a market for Wi-Fi microphones.

~~~
stretchwithme
Looking at what's on Amazon, this doesn't seem like an expensive problem to
resolve.

Most people already have all they need for a wifi microphones in their
pockets, albeit probably not of the same quality as professional systems.

The unfortunate thing is that their is no mechanism for selling the right to
use this spectrum for all those who've made investments in such devices. It
may be worth millions to discontinue their use of it and it may only be worth
thousands to existing users, but no way for high value potential users to
compensate the current users.

Of course, if spectrum were treated like property or you had to pay to rent
what you use, everybody could buy or rent what they need.

~~~
superuser2
I don't know what you're seeing on Amazon, but there is a lot of cheap crap
out there that, unfortunately, doesn't work reliably enough or sound good
enough to use in a performance setting. Audio Technica 3000-series [1] is
about the cheapest thing that's decent (my middle school operated 16). Note
the frequency band options.

WiFi in particular is not designed for a 100% stable connection with low
latency and no jitter, and good luck getting it to do that. You can power-
cycle your laptop's WiFi every few hours; you can't lose the lead singer in a
musical or the pastor in a church service. There are digital, frequency-agile
wireless systems like ULX-D [2] which are a little better at dealing with
crowded RF landscapes, but this is still low-middle tier. UHF-R is a tier
above that, starting around $2000 per system. The gear for really challenging
RF environments is Shure Axient, and you can't even get pricing on that
without talking to a high-end certified distributor, but anecdotally the
transmitters are about $3,000 and a dual-channel receiver is $7,500.

[1] [http://www.amazon.com/Audio-Technica-ATW-3131BD-Wireless-
Lav...](http://www.amazon.com/Audio-Technica-ATW-3131BD-Wireless-Lavalier-
System/dp/B003R6V5QM/ref=sr_1_1?ie=UTF8&qid=1439674281&sr=8-1&keywords=audio-
technica+300)

[2] [http://www.amazon.com/Shure-
ULXD24-B87A-G50-Handheld/dp/B008...](http://www.amazon.com/Shure-
ULXD24-B87A-G50-Handheld/dp/B008BMHAKC/ref=sr_1_4?ie=UTF8&qid=1439674532&sr=8-4&keywords=shure+ulx-d)

[3] [http://www.shure.com/americas/products/wireless-
systems/uhfr...](http://www.shure.com/americas/products/wireless-systems/uhfr-
systems)

It's tempting to think of the problems in fields other than your own as
trivial, but please don't fall into that trap. You don't want to hear a play
through Skype on iPhones (which is a moot point, because you wouldn't anyway).
Reliable RF audio that sounds good is a hard/expensive game and eliminating TV
whitespace fucks over people who are playing in the lower/middle tiers.

~~~
TrevorJ
This is all very true.

------
jrockway
All of the recent research I've seen on this topic seems to be moving in the
wrong direction. WiFi is a shared channel, if someone is using it, you can't
use it. Thus it makes sense to _minimize_ the range as much as possible; if
your walls are attenuating the signal, that's great, because it means your
neighbors can't interfere with your network. 2.4GHz and 5GHz already have too
high of signal penetration (I see tens of networks on 2.4GHz in my apartment
in Brooklyn), going down to 900MHz or 700MHz just means that if anyone in your
city is using the channel, you can't use it. Needless to say, this is not
going to make your WiFi experience more enjoyable.

Everyone hates running cables to the various floors of their houses, so I
understand why people want more range. But more range for you means more range
for other people, which means more interference.

Much of this can be mitigated by using a multiplexing mechanism more
intelligent than carrier-sense, like CDMA. But as far as I can tell, the
industry is resisting this heavily. LTE-U sounds like the idea is to bring LTE
signalling to the unlicensed bands, so you can replace your WiFi router with
an LTE router and have better use of the channel capacity (and sharing with
other LTE networks). But the industry appears to be uninterested in this use
case, instead focusing on tapping the ISM bands for more cell phone capacity.

TLDR: stock up on Ethernet cables. Sigh.

~~~
Gibbon1
I had that gut reaction as well when listen to a marketing guy talk about
devices with 5-10 mile range at 900MHz. The 900MHz band is 30 MHz. Not much
when you consider population densities of 5-20,000 people per square mile.

Side: I'm not really a WiFi guy but I think WiFi is based on listen before
talk would means things like latency are going to be not so good when you have
a lot of nodes. Not surprising because WiFi is basically 'wireless Ethernet'
and has it roots in file transfer applications.

I think LTE Unlicensed, developed by telephony guys will probably be better at
serving low/deterministic quality of service applications in high traffic
areas. Also rather than disinterest it's a matter that of some companies are
interested in the technology and others see it as a threat. However what I
read is they are talking about LTE-U on the 5.8GHz band.

~~~
jrockway
That's exactly right, and you bring up another few good points.

1) 802.11ac is 80MHz. If you are just getting a few megahertz between TV
stations (I couldn't find the exact number), you aren't going to get your
1Gbps transfer rates with the signalling that WiFi uses. (In fact, you rarely
get them in lab conditions, but I digress.)

2) With WiFi's signalling, multiple transmissions stomping on top of each
other simply make both transmissions fail. LTE uses different sets of "tones"
so that transmissions stepping on each other are still recoverable. (This is
like how all the GPS satellites transmit on the same frequency, but you can
still hear 10 of them at once. Clever math.)

Certainly, I'd like to see unlicensed city-level wireless Internet that
behaves as well as carrier-run LTE networks. You may not get a gigabit but
even slow Internet is better than nothing. If anyone is researching this I'd
be glad to send some donations their way :)

------
hwstar
This is a really good idea. We should refarm 400-700MHz over the next 10 years
and use it for Internet service. The broadcasters will eventually be forced
out of business due to IPTV. Have you seen the kind of programming currently
broadcasted by some of these UHF non-network TV stations in big cities?

It's dreck.

The non-network TV broadcasters are desperate for audiences which aren't
watching their programs, and therefore the ads interspersed in these programs.
Their businesses will fail in due time as more people switch to IPTV.

The only snag I see is how to broadcast emergency messages over IPTV. This is
something which needs to be resolved before we refarm the UHF TV band.

~~~
toomuchtodo
Push notifications for emergency broadcasts. Receive only RF chipsets if
absolutely required.

~~~
zimbatm
Notifications are location dependent. How do you solve the issue without
having everyone publishing their location all the time ?

~~~
throway0815a
You encode the location information in the actual broadcast message:

[https://en.wikipedia.org/wiki/Specific_Area_Message_Encoding](https://en.wikipedia.org/wiki/Specific_Area_Message_Encoding)

This is a solved problem: weather radios have been doing this for years.

------
callesgg
The range of those bands means one has to share them with allot more people.

Resulting in lower bandwidth per person.

~~~
Zigurd
If APs are cheap, you can get very high capacity by deploying more APs and
managing transmission power so as not to step on adjacent APs. The trick is to
make the radios smart enough to make coverage good enough without having a
carefully designed deployment of APs.

Hopefully we can leave the antediluvian idea of "spectrum ownership" behind.

------
stretchwithme
Why should specific frequencies be assigned for specific uses anyway? Can't we
have a marketplace for spectrum in which devices can get access to the most
appropriate spectrum in realtime?

Spectrum is expensive because we waste so much of it. If users had an
incentive to use the least usable frequencies when they do work, there'd be
more room in the most usable frequencies for applications that require those.

As it turns out, the FCC has approved sharing rules for the 3.5 gigahertz
spectrum. Maybe this will demonstrate how much better the future can be.

    
    
      http://www.rcrwireless.com/20150515/test-and-measurement/isart-2015-google-spectrum-sharing-3-5-ghz-tag6

------
z3t4
I'm generally against radio communication because everyone has to share the
wavelengths.

It would however be very cool and cost effective if you could "peer" over
radio link instead of digging cable trenches through cities and people's
properties.

With smart access points, they could cooperate to not interfere.

------
ucho
In middle of title I thought it would be about finally killing tabs.

