Post DSO - Here comes White Space

RangeR

Fascinating read on how OFCOM [UK] are looking to maximise White Space use.

Have a read over their consultation paper URL="http://stakeholders.ofcom.org.uk/binaries/consultations/whitespaces/summary/condoc.pdf"]PDF[/URL. If yer into that sort of thing, makes for a great read.

Now.... Just have to wait a decade or two before we get our ass in gear.

Sponge Bob

White space is snakeoil really. It means that the regulator will allow interference with TV signals (in effect) while protecting mobile signals just above the TV bands. Look at the mess that Powerline tech has made of lower frequency bands.

ozymandius

RangeR wrote: »

Fascinating read on how OFCOM [UK] are looking to maximise White Space use.

Have a read over their consultation paper URL="http://stakeholders.ofcom.org.uk/binaries/consultations/whitespaces/summary/condoc.pdf"]PDF[/URL. If yer into that sort of thing, makes for a great read.

Now.... Just have to wait a decade or two before we get our ass in gear.

A bit cynical maybe. Its not as bad as you think. We have some world-leading researchers in that area.

http://www.ctvr.ie/News-and-Events/News-Listing/Filling-the-White-Spaces

watty

We have some world leading idiots.

It will cause interference to TV viewers. The Mobile operators would never agree to their "White Space" being misused like this.

The scheme is impossible to police and is so prone to cause interference to non-White Space devices that it's a disaster and vandalism.

So why doesn't someone suggest a way of dealing with the
issue(s) surrounding "retransmission/rebroadcasting"? (to give it a name)

Theoretically and demonstrated in practice there is no solution

This is why particular bands or channels are usually licensed on a NON shared basis. One organisation decides physically where each channel is used. It's called Radio or Network planning and is highly skilled.

Ad hoc networks are VERY problematic as anyone trying to make Video Senders and WiFi co-exist.

The only reasonable solution for so called "White Space" licence free user located two-way devices is a band dedicated to it.

WiFi points and Analogue Video Senders and other 2.4 & 5.8 GHz devices would be improved using the central database suggested for so called "White space" especially WiFi used for Outdoor links. It would not entirely mitigate the problems.

It can NEVER work in a band used by non-White space devices, EVERY TV and setbox would need to be on the Internet reporting what channels it uses. Also people will add "illegal" gain of aerials, disable the database, or not be able to get an Internet connection for the Database or add more power. Even if it could work (and it can't ever) it's impossible to police!


"White Space" is a fantasy scheme

I can demonstrate with modified WiFi points (to use a shared Database) and Video Senders/Receivers (simulating legitimate TV users) that it really can't ever work.

Read the comments here
http://forums.theregister.co.uk/forum/1/2012/11/23/white_space/

ozymandius wrote: »

A bit cynical maybe. Its not as bad as you think. We have some world-leading researchers in that area.

http://www.ctvr.ie/News-and-Events/News-Listing/Filling-the-White-Spaces

It's far worse than you think. CTVR have no evidence to prove this works. There is PLENTY to prove it doesn't.

What is the actual commercial or properly peer reviewed success of Linda Doyle's CTVR empire?

Why is the Tax payer's money being wasted on them? This is idealogical hogwash.

ozymandius

watty wrote: »

We have some world leading idiots.

It will cause interference to TV viewers. The Mobile operators would never agree to their "White Space" being misused like this.

The scheme is impossible to police and is so prone to cause interference to non-White Space devices that it's a disaster and vandalism.



Read the comments here
http://forums.theregister.co.uk/forum/1/2012/11/23/white_space/

What is the actual commercial or properly peer reviewed success of Linda Doyle's CTVR empire?

Why is the Tax payer's money being wasted on them? This is idealogical hogwash.

So ... I should put more faith in (of all places) The Reg's comments section?

Are these rhetorical questions? You seem bitter. I was answering a specific point raised by RangeR.

watty

I am bitter when I KNOW the state's money is been wasted for years and Comreg listens to these people.

Capt'n Midnight

White space can be done two ways.

One is a central database. This means that all devices already have connectivity so no point in using for low bandwidth uses. So high bandwidth uses.

The other is where all the devices use some sort of collision detection algorithm and back off politely. A rogue device (cheap Chinese knock off) that doesn't back off will always win against a more expensive standards compliant device. Guess which one people will buy ? (there is also the hidden node problem, which is compounded by flight times in the order of a small packet)

Digital signals have forward error correction and it is absolutely amazing in handling short term spikes. But you have to remember that continuous noise will eat into the margin.

watty

Even using both (as proposed) only works NEARLY, if EVERY device is such a device, TVs and Set boxes will just suffer interference and do not report to the database.

An accurate database is impossible as the RF models of the Topology are neither good enough terrain, accurate enough nor can know what height of pole and gain of aerial is in use to get TV (or by the so called "white space" device).

It's been known for 60 years that the collision detection is REALLY Poor EVEN when every device is using the same protocol. The issue is called "hidden transmitter" syndrome.

There is absolutely NO solution except to give such devices their own band. (Making EXISTING WiFi use these two schemes would be a start, but it is TOO expensive and impracticable to make non-Internet or non-data devices use the same protocol, so they WILL suffer interference, just as they do today EVEN if this is fully implemented for wifi).

It's worth doing with WiFi. It's criminally irresponsible to licence such gadgets on a band used by something else. In this case TV.

I ask CTVR to see what the Mobile Operators think of retail licence free gadgets using the "white space" on Mobile bands on same basis. They would be laughed at and door slammed in their face. There is NO difference with TV, except it's a softer target.

The technology existed to do this cheaply 10 years ago on Analogue TV band, in no worse a fashion. They are using the excuse of "Digital Dividend" and the US Term "White Space" and the ASO to try and slip this dirty technology ON the actual Digital TV channels.

People would have NO idea why they suddenly lose reception. Comreg takes already 6 to 9 months to sort Interference issues and is trying to even avoid being responsible for 800MHz LTE (an actual SEPARATE band) interfering with Digital TV, Cable TV and Cable Broadband. It will interfere.

zg3409

To be fair, and I am not a big fan of this technology, there must be parts of the country where Mux 3 will not be used for years (if ever) and so in these areas the spectrum is being wasted for years and the "losses" can never be reused.

A little like 100FM to 108FM was left blank for years for no real good reason.

As to how useful these devices could be is very dependant on how they are used in practice. For real commercial high speed broadband provision in rural areas the low frequency combined with possible non line of sight means the capacity would be very limited.

As mentioned by Watty if used they would definitely cause problems. Those who suddenly have TV issues may never realise what is happening and a proper solution. It is similar to people complaining about slow broadband, when the local wifi is the actual problem. The devices (laptops) do not warn of interference and most do not even indicate which channel is in use.

watty

It's a Genie that can't ever be let out. What about when Mux3 or Mux6 is needed?

Also people would add high gain aerials, booster amps, disable database. Even if there was a very proactive Regulator it's a nightmare to police compliance. In practice an Interference Complaint could take 6 months to a year to sort out. If it's Licence free as CTVR argues, who pays for the 100s of staff needed to police it?

100MHz to 108MHz wasn't used for Broadcast in UK because the State Services were using it!

We have perfectly good technology and bands for real Fixed Wireless Broadband. But it's not economic due to the cross subsidy of Mobile Data by voice and the perception fostered by Government, Comreg, DCENR and Mobile Operators that Mobile is Broadband. It's not and LTE won't be either, it's MOBILE Internet. Not a replacement for Fixed Broadband, but a complementary service.