How new 'white space' rules could lead to an urban super-Wi-Fi | Hacker News Reader

How new 'white space' rules could lead to an urban super-Wi-Fi

computerworld.com

47 pointsdoener25 comments

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.

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

Like I said, the big corporate rental houses can buy new inventory. Schools, churches, and nonprofit/educational theater cannot.

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.

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...

[2] http://www.amazon.com/Shure-ULXD24-B87A-G50-Handheld/dp/B008...

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

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.

This is all very true.

A smart protocol that could share with unlicensed devices would seem to relieve your concerns. It should be possible.

I stand corrected.

I don't think this is of the same order of magnitude importance as the potential for wifi.

For any policy change, you can find some case where it negatively affects someone. Churches, schools and nonprofit theaters might tug on the heartstrings but if as a society we really thought these things are incredibly underfunded (I don't) then we could just give them money directly through government grants.

Government policy must be able to change, and there is no guarantee of compensation when it does. To do so would be prohibitively expensive, since the government never receives any money when people indirectly benefit from its policies.

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

I think it is for the greater good, and I accept the negative consequences while I cheer it on. Are you saying this is a bad policy, or do you just want people to feel bad anyway?

>you can find some case where it negatively affects someone

But what form does that take? Certainly we cannot compensate people when we take away their government funding or contracts, that would be absurd. And where there is a degree of blame involved (like polluters) we require that they clean up their own mess.

But when government seizes someone's real estate through eminent domain, it's required to pay them fair market price for it.

When government decides that your car is unsafe, it doesn't require you to scrap it and buy a new one at your own expense - the manufacturer does a recall.

When government decides to change the building code, old buildings are generally allowed to stay as they are until they perform extensive renovations (indicating that they have the financial means to become compliant again).

Can you provide an example of a case where a nonprofit entity is just humming along, and then out of nowhere the government forces them to throw away their capital equipment?

> Are you saying this is a bad policy

Maybe. Since we're losing something, we'd better actually be winning something. Comcast has been extremely successful at passing state laws to block municipal fiber buildout. What makes you think Comcast's lobbyists will ever allow citywide WiFi to see the light of day? Perhaps this can be addressed by allowing wireless mics to continue functioning until service on this band is actually going to be rolled out.

Is WiFi even the right approach? If you want a world without bandwidth rationing, then fiber is the way to go. Choosing RF as our path forward means we throw in the towel on that one and accept that people will always have to regulate their appetite for bandwidth.

Are there technical reasons we can't use 4G/LTE to provide the same service, or simply the strategies of the carriers to extract the most rent possible from the least infrastructure?

An enormous portion of the spectrum is reserved for military and government. Is that necessary? Is that even a good thing for military and government? We're constantly hearing about different agencies, branches of the military, and even divisions within a branch not being able to talk to each other because they use different radios. Could we consider consolidating some of that spectrum using the medium-sharing algorithms we know about now, and end up with better service for government and more space for the private sector? Probably.

Isn't this what WiMax was supposed to be? What happened to that?

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.

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.

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 :)

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.

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

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

Only broadcast them from towers near the emergency. Or tag each notification with an affected area and let the device decide if it's applicable.

You encode the location information in the actual broadcast message:

https://en.wikipedia.org/wiki/Specific_Area_Message_Encoding

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

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

Resulting in lower bandwidth per person.

I agree. It'd be great to have more frequency bands, but if we're all on the same wifi, what if someone starts downloading obscene amounts of data?

That's true, if one is using the same kind of radio tech that Marconi used. Fortunately numerous techniques for intelligently sharing spectrum have been developed. R&D in this area will only accelerate when applications like those described in TFA are finally allowed.

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.

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

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.

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

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