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Comments on news posted 2008-11-05 08:56:33: Google co-founder Larry Page recently dubbed white space broadband technology "Wi-Fi on steroids," and declared that he was "100 percent confident" that white space broadband is inevitable. ..

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pende_tim
Premium Member
join:2004-01-04
Selbyville, DE

pende_tim

Premium Member

Time Line

So what is the timeline for devices to start showing up in the consumer market? Can the NAB or Shure block implementation?
nasadude
join:2001-10-05
Rockville, MD

nasadude

Member

NAB

No Alternative Broadband
Sammer
join:2005-12-22
Canonsburg, PA

Sammer

Member

OET is not independent!

Yesterday the head of the FCC Office of Engineering and Technology Lab seemed to be very nervous during his presentation. Afterwards FCC Commissioners inappropriately and disrespectfully joked about giving out his home phone number. It seems that in recent years the FCC Commissioners can get any result they want from the OET.

funchords
Hello
MVM
join:2001-03-11
Yarmouth Port, MA

funchords

MVM

He was nervous because he lost his place after page 1 of his presentation.

Also, this was one of the most-watched, heavily-scrutinized processes that the FCC has followed in recent years. And after all was said and done (and redone, and watched), the NAB and microphone folks made it clear that the science didn't matter.

The joke was a joke. The disrespect was part of the punchline. Don't take humor seriously.

phoneboy3
@shawcable.net

phoneboy3

Anon

Probably a couple years

I would not expect to see any sort of deployments for at least 2 years. Probably more for business/political reasons than technical.

They will probably want to get this standardized asap but that will take time. Nothing stopping people from deploying proprietary systems in the mean time though.

This is a big deal for underserved communities and ultimately gives us more choice so it's a win win for consumers IMHO.

FFH5
Premium Member
join:2002-03-03
Tavistock NJ

FFH5 to pende_tim

Premium Member

to pende_tim

Re: Time Line

said by pende_tim:

So what is the timeline for devices to start showing up in the consumer market? Can the NAB or Shure block implementation?
Lawsuits will be coming.
Sammer
join:2005-12-22
Canonsburg, PA

Sammer to funchords

Member

to funchords

Re: OET is not independent!

I can tell when someone is treated as a subordinate (by more than one of the Commissioners) rather than as a respected independent engineer!
Sammer

Sammer to phoneboy3

Member

to phoneboy3

Re: Probably a couple years

said by phoneboy3 :

This is a big deal for underserved communities and ultimately gives us more choice so it's a win win for consumers IMHO.
"The Devil is in the details." While this may prove ideal for some rural areas, "not just WiFi on steroids but on amphetamines" (both references to drug abuse) could mean things could get real ugly in RF congested urban and suburban areas.
JSM
join:2000-12-20
Falls Church, VA

JSM to FFH5

Member

to FFH5

Re: Time Line

But but but... I thought Trial Lawyers were evil TK? You and your repu colleagues keep telling me so. We have to STOP them. I got it, we'll take away the right of companies to sue the federal government, sovereign immunity and all that, that will cut down on these frivolous suits. Thanks for the idea.
Sammer
join:2005-12-22
Canonsburg, PA

Sammer to FFH5

Member

to FFH5
said by FFH5:

Lawsuits will be coming.
Maybe not just yet. Hillary Rodham Clinton may still have something to say about implementation. What cabinet post do you suppose Obama will offer her, Attorney General maybe?

funchords
Hello
MVM
join:2001-03-11
Yarmouth Port, MA

funchords to Sammer

MVM

to Sammer

Re: OET is not independent!

I detected nothing but fondness. While I haven't met the engineer, I've met the commissioner.

MrMoody
Free range slave
Premium Member
join:2002-09-03
Smithfield, NC
Netgear CM500
Asus RT-AC68

MrMoody

Premium Member

Free TV, we hardly knew ye

Before quality, free TV can barely get out of the gate, they kill it off in a mad rush to get it done before the party change. The cablecos (not to mention DBS, ATT & VZ) should be gleeful, they just defeated a huge threat to their TV business.

For those who think I'm spewing FUD, here's some math with references. First of all I will state that I am a licensed radio amateur who had to pass tests on radio theory and propagation to get my license. I know what a dB is and how to do math with it.

In my neighborhood, the average house interval is 180 ft. I've lived in other, modern places where it was less than half that, and older neighborhoods where it was only about 40 ft. Depending on neighbors' antenna and WSD positioning within each house, the distance between them could easily get down well under 20 ft.

But we'll use my 180 ft. as an example.

The ATSC standard recommends a receiver sensitivity of -83 dBm. In my experience, getting a usable signal requires better than -83 dBm field strength at the antenna. The gain of the antenna roughly equals the losses in the cables and tuner noise. Below that level, the signal becomes unreliable and starts glitching frequently in a most annoying manner, or won't appear at all.

My IN-MARKET PBS station is about 50 miles away, and arrives at my antenna at a strength of about -80 dBm according to the signal calculator at www.tvfool.com. Their estimates are a little optimistic due to not counting obstructions such as trees. This signal I would rate at 90% reliable; it works fine most of the time but occasionally glitches out when the wind blows and at other random times.

According to tests performed by the Communications Research Centre Canada(PDF), consumer DTV receivers can only tolerate an adjacent channel signal 31-40 dB above the desired signal before failing. By the way, the WIA conveniently ignores these tests and instead relies on tests they funded themselves.

Going back to my example, after the transition, PBS will transmit on UHF 25 and arrive here at a strength of -74.7 dBm. According to the above, any signal on 24 or 26 at a level above -44 dBm is increasingly likely to interfere with consumer receivers.

Now assume my neighbor gets a WSD which finds channel 24 (centered at 539 MHz) to be available. The WIA claims that 100mW won't interfere with adjacent channels. So, we plug in some numbers in to the online Friis Transmission Equation Calculator. The receive antenna gain is irrelevant because it applies equally to the desired and interfering signals.

The result: Using a built-in WSD antenna gain of 0 dBi, we get a strength at 180 ft. away of -41.8 dBm. Subtract, and this would exceed my PBS signal by 32.9 dB, enough to interfere with some receivers. If the desired signal was at -80 (still within FCC reception spec), it would interfere with ALL receivers tested. Make the WSD closer, or FCC forbid, connect it to an antenna with GAIN (any old consumer UHF TV antenna will do, which the WSD users will QUICKLY discover increases their range tremendously), and now it is CERTAIN to wipe out low-strength adjacent channels on virtually ANY consumer receiver.

Any questions?

In order to truly prevent adjacent channel interference, either (1) they'd have to disable adjacent channels, which would leave very few channels available most places, or (2) limit the power so that the level at the neighbor's TV antenna is -52 dBm (-83 minimum signal plus 31 interference level) or less; at a generous neighbor distance of 60 ft. this works out to under 1 mW(!) AND there would have to be no way to increase power or connect an external antenna to it. Good luck with that one.

Ah well, unless the new FCC stops this madness, which truly has little value as broadband as I've already argued previously, I guess in a couple years I will be buying wireless mics to "stake claim" to my TV reception channels by bumping off the sensing WSDs. And the airwave pollution war begins.

FFH5
Premium Member
join:2002-03-03
Tavistock NJ

FFH5 to Sammer

Premium Member

to Sammer

Re: Time Line

said by Sammer:
said by FFH5:

Lawsuits will be coming.
Maybe not just yet. Hillary Rodham Clinton may still have something to say about implementation. What cabinet post do you suppose Obama will offer her, Attorney General maybe?
She won't leave the Senate to work for Obama.
rody_44
Premium Member
join:2004-02-20
Quakertown, PA

rody_44 to MrMoody

Premium Member

to MrMoody

Re: Free TV, we hardly knew ye

airwaves pollution keeps the fcc in bussiness. why wouldnt they want that.

anon12
@direcpc.com

anon12 to MrMoody

Anon

to MrMoody
yea yea yea who cares you could have saved yourself a lot of time typing.its been voted in and time for you to shut the hell up,and just wait and see how good,or bad it works

MrMoody
Free range slave
Premium Member
join:2002-09-03
Smithfield, NC
Netgear CM500
Asus RT-AC68

MrMoody

Premium Member

said by anon12 :

you could have saved yourself a lot of time typing.
Thank you for your concern, but don't worry, it wasn't time wasted. I kept a copy to mail in writing to the new chairman when he takes office.

anan12
@direcpc.com

anan12

Anon

surely you don't think he will give a crap about you opinion

GeekJedi
RF is Good For You
Premium Member
join:2001-06-21
Mukwonago, WI

GeekJedi

Premium Member

Yes, Mr. Anonymous troll, he will.

This is far from a done deal. There will be hearings and lawsuits, and if I were a bettin' man, I'd be betting that just like the BPL debacle, this will go away.
RobertJTownley
join:2001-04-13
Omaha, NE

RobertJTownley

Member

How does uploading work on White Space Broadband.

How does uploading work (if at all) on a whitespace link? Is it just like most consumer satellite connections, dial-up modem for uploads?
i haven't been able to get my hands on IEEE 802.22, but would think something designated as 802 would be duplex. Need a reference though.

anon12
@direcpc.com

anon12 to GeekJedi

Anon

to GeekJedi

Re: Free TV, we hardly knew ye

said by GeekJedi:

Yes, Mr. Anonymous troll, he will.

This is far from a done deal. There will be hearings and lawsuits, and if I were a bettin' man, I'd be betting that just like the BPL debacle, this will go away.
excuse me IM a troll because i have a wait and see attitude.you all want to shoot everything down before you even know how good or bad it will work.if that makes me a troll then so be it at least IM a little bit optimistic which is something that cant be said about you and moody

phoneboy3
@shawcable.net

phoneboy3 to GeekJedi

Anon

to GeekJedi
This is NOT the same as BPL. The important distinction is that this works.

anon12
@direcpc.com

anon12 to GeekJedi

Anon

to GeekJedi
FYI bpl is still being used,it hasn't all gone away yet
Sammer
join:2005-12-22
Canonsburg, PA

1 edit

Sammer to RobertJTownley

Member

to RobertJTownley

Re: How does uploading work on White Space Broadband.

said by RobertJTownley:

How does uploading work (if at all) on a whitespace link?
Apparently Orthogonal Frequency-Division Multiple Access (OFDMA) the same thing that is used for mobile Wi-Max will be used. Speed will probably be dependent on how much white space spectrum is available.

DavePR
join:2008-06-04
Canyon Country, CA

DavePR to funchords

Member

to funchords

Re: OET is not independent!

said by funchords:

...the NAB and microphone folks made it clear that the science didn't matter.
The science says it won't work. Read the engineering study before you make these pronouncements. The FCC decision was 100% political.
DavePR

DavePR to anon12

Member

to anon12

Re: Free TV, we hardly knew ye

The FCC engineers proved it won't work, which was massaged into "proof of concept" by politicians. If you read their paper you'll see that. The numbers don't add up.

The only device that detected broadcast stations 100% was the one that used the FCC database, not spectrum sensing. Now we're talking about a box with GPS and internet access, that will not transmit until it knows where it is and can download a file from the internet without transmitting. Will it have to have a phone line?

Google needs to be slapped down. They do plenty of evil.
DavePR

1 recommendation

DavePR

Member

Why Not WiMax?

It seems way more promising than this controversial Rube Goldberg idea?
Sammer
join:2005-12-22
Canonsburg, PA

2 edits

Sammer

Member

WiMax is way more promising except in some very rural areas but the white space proponents didn't want to pay for spectrum the way what is now the New Clearwire had to. IMHO the spectrum licenses that will now be used to provide mobile WiMax service should have been paired with white space licenses out in the middle of nowhere where it would be almost impossible to interfere with television reception but would have made the build out of a national WiMax network less expensive where it would do the most good.

funchords
Hello
MVM
join:2001-03-11
Yarmouth Port, MA

funchords to DavePR

MVM

to DavePR

Re: OET is not independent!

Dave, I read the study (it's about an inch thick).
Sammer
join:2005-12-22
Canonsburg, PA

3 edits

Sammer to MrMoody

Member

to MrMoody

Re: Free TV, we hardly knew ye

said by MrMoody:

Ah well, unless the new FCC stops this madness, which truly has little value as broadband as I've already argued previously, I guess in a couple years I will be buying wireless mics to "stake claim" to my TV reception channels by bumping off the sensing WSDs. And the airwave pollution war begins.
Madness is right on the very same day the FCC approved white space devices the FCC also approved, after a successful 5 year trial by WPSU in Central PA, Distributed Transmission Systems for licensed digital television stations. Of course the main opponents to DTS were the white space proponents because it could actually fill gaps and improve television reception in underserved communities not to mention enable the use of the future ATSC mobile / handheld standard. Some WSD proponents are quite concerned that DTS could lead to tens of thousands of TV transmitters. IMHO the WSD proponents shouldn't be concerned because they are just small transmitters with a couple kW each and could provide innovative television services to millions.

DavePR
join:2008-06-04
Canyon Country, CA

DavePR to funchords

Member

to funchords

Re: OET is not independent!

Are you an RF engineer?

The test results do not support any conclusion other than that a device that relies on sensing alone cannot work.

Devices that use geolocation and database access can avoid stepping on incumbent users, but only if they consult the database before turning on; and only if the database is maintained in real time.

Two questions: How would the device know where it is? How would the device access the database without transmitting?
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