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Comments on news posted 2011-10-13 08:22:19: After both GPS-related industries and government agencies highlighted that LightSquared's planned LTE/Satellite hybrid network interfered with GPS signals, the company in June LightSquared filed a revised plan with the FCC. ..

page: 1 · 2 · 3 · next


marigolds
Gainfully employed, finally
Premium,MVM
join:2002-05-13
Saint Louis, MO
kudos:2

GNSS is not the solution

As I said on the last article like this...
Javad uses the Russian GNSS location system.
That simply is not an acceptable solution for US industries, especially defense related (the DOD itself has its own frequencies).
While GNSS is a good complementary system, you have to have high accuracy GPS with it.


mod_wastrel
iamwhatiam

join:2008-03-28
kudos:1

Truth or FUD?

"...the GPS industry should have vacated the spectrum years ago"


ArrayList
DevOps
Premium
join:2005-03-19
Brighton, MA

all I hear is...

WHAAAAAAAAAA WHAAAAAAAAAA WHAAAAAAAAAA we have to spend money to fix or borked equipment.


keyboards

join:2001-02-14
Doylestown, PA
said by ArrayList:

WHAAAAAAAAAA WHAAAAAAAAAA WHAAAAAAAAAA we have to spend money to fix or borked equipment.

There is nothing wrong with anyone's equipment. Light Squared wants to use spectrum that impinges on high accuracy GPS systems. These systems are integral to air safety as well as our military (all of which had systems that were designed to the standards that Light Squared now wants to infringe on).

As a more technical explanation, because of the spread spectrum nature of the signals, the "skirts" now can intersect if Light Squared does not provide a sharp enough filter on their transmission. Their "solution" is to force a front end filter on the high precision GPS receivers rather than controlling their own power spectrum AND expect the existing device owners / manufacturers to foot the bill.
--
REMEMBER: Stupidity should be painful !!


FFH5
Premium
join:2002-03-03
Tavistock NJ
kudos:5

Lightsquared - chutzpah

Lightsquared becomes a synonym for chutzpah.
»www.merriam-webster.com/dictiona ··· chutzpah

Demanding those who are victims of interference caused by your company should pay for the fix is truly arrogant.
--
»www.rickperry.org/

openbox9
Premium
join:2004-01-26
Germany
kudos:2
reply to ArrayList

Re: all I hear is...

LightSquared? It seems to be doing the most whining. Maybe like a 2-yr old it hopes that if it cries enough it will get its way.


pjcamp

@comcastbusiness.net
reply to mod_wastrel

Re: Truth or FUD?

According to the cNet article: "The GPS industry has long relied on equipment that relies on spectrum which bleeds into the spectrum that LightSquared plans to use for its network. While the industry had been warned of its potential use, the GPS companies opted not to change the design of their devices or shield them against potential interference"

So if true, yes, it is the GPS industry's responsibility. They cheaped out and bled into spectrum they are not licenses to use, assuming it would be ok since no one else was using it either, at the time. Now someone is and it is no longer ok. But that was bad design on their part, and in any case you're not entitled to bleed into spectrum blocks that you don't own. Lightsquared seems to be blameless on this particular issue.

openbox9
Premium
join:2004-01-26
Germany
kudos:2
reply to FFH5

Re: Lightsquared - chutzpah

LightSquared is running out of options. It's been throwing around billions of dollars for a while now without much to show for it. Investors are growing more and more wary. The company has to do something.


ArrayList
DevOps
Premium
join:2005-03-19
Brighton, MA
reply to keyboards

Re: all I hear is...

light squared wants to use spectrum that they paid for.


Tomek
Premium
join:2002-01-30
Valley Stream, NY
said by ArrayList:

light squared wants to use spectrum that they paid for.

Then lightsquared should sue them for unlicensed use of their spectrum
--
Semper Fi


n2jtx

join:2001-01-13
Glen Head, NY
reply to ArrayList
said by ArrayList:

light squared wants to use spectrum that they paid for.

They didn't pay for it. SkyTerra got it for free and LightSquared bought them out. What LightSquared really wants, according to industry analysts, is a frequency swap for more valuable spectrum WITHOUT having to pay for it. They are basically holding GPS hostage in the hopes the government will pay them off with frequencies that could otherwise be auctioned off.
--
I support the right to keep and arm bears.

openbox9
Premium
join:2004-01-26
Germany
kudos:2
said by n2jtx:

What LightSquared really wants, according to industry analysts, is a frequency swap for more valuable spectrum WITHOUT having to pay for it.

Given the FCC's bungling of this whole Charlie Foxtrot, that's exactly what needs to happen. Swap spectrum, eliminate/mitigate the interference issues, and most everyone is happy.

jagged

join:2003-07-01
Boynton Beach, FL
reply to FFH5

Re: Lightsquared - chutzpah

said by FFH5:

Lightsquared becomes a synonym for chutzpah.
»www.merriam-webster.com/dictiona ··· chutzpah

Demanding those who are victims of interference caused by your company should pay for the fix is truly arrogant.

how about lazy and stingy sat equipment makers actually fix their wares? Tho I'm sure with AT&T involved there will be some excuse for that not to happen

xenophon

join:2007-09-17

2 edits
reply to pjcamp

Re: Truth or FUD?

Yeah, the GPS industry is at fault here. If they use spectrum they are not allocated to, they obviously either need to fix it or buy the spectrum from LS.

There's only so much spectrum to go around though and the future of wireless is more and more data - that spectrum is highly valuable. The FCC needs to set a timetable for the GPS industry to clean up the mess with major fines as a consequence. If the net fines are over $400M, then the LS proposal might be taken seriously by the industry.

openbox9
Premium
join:2004-01-26
Germany
kudos:2
said by xenophon:

The FCC needs to set a timetable for the GPS industry to clean up the mess with major fines as a consequence.

Actually, since the regulatory body responsible for mitigating spectrum interference is at fault for allowing this situation to happen, it needs to resolve this dispute. Spectrum reallocation is the best solution IMO.


DaveRickmers

join:2011-07-19
Canyon Country, CA
reply to pjcamp
Wrong! GPS receivers do not "bleed". GPS transmitters are hundreds of miles away and the receivers must be very sensitive and must fit in a postage stamp sized device. Spectrum is not "brick wall"; there are guard bands to protect sensitive receivers all over the allocations. Lightsquared ASSUMED they could do whatever they want with the spectrum because they were getting bad advice from someone sorely lacking any real world RF experience. Caveat emptor! They got hosed. Get over it.

xenophon

join:2007-09-17
reply to openbox9

Re: all I hear is...

It's seems to be justified though. LS bought the spectrum so they have a right to use it. The GPS industry is bleeding into their space. The FCC is partly at fault for allowing LS to buy it but the GPS industry was apparently warned about bleeding into that spectrum.

The GPS industry needs to fix this whether LS exists or not because they are wasting a lot of valuable spectrum for a simple function that doesn't need much data.

MaynardKrebs
Heave Steve, for the good of the country
Premium
join:2009-06-17
kudos:4
reply to ArrayList
LightSquared wants to use those frequencies -originally intended for use from space (ie. low power when actually received on Earth) - in a way that they were NEVER intended to be used (ie. high power terrestrial transmissions) which will overpower the receivers on ground-based GPS systems.

If these frequencies are used as originally intended there would be NO interference with ground-based GPS as the GPS receivers are able to filter out the low-power 'noise' in those frequency bands.

What LightSquared is proposing is like a 5 milliwatt baby crib monitoring radio with a 50' range suddenly boosting it's output to 100KW and clobbering all receivers within a 100 mile radius.

Do you ever wonder why AM or FM radio stations are separated by the amounts they are on the radio dial? It's because of interference. Ditto with GPS frequencies and those that LightSquared got their hands on. It's the FCC that screwed up here by letting the GPS guard bands get overrun by LightSquared's shift to high power terrestrial use. Had LightSquared stuck to space-based use of these frequencies, we would not be having this conversation

brugar

join:2002-09-16
Las Vegas, NV
kudos:2
reply to jagged

Re: Lightsquared - chutzpah

LightSquared becomes a synonym for chutzpah.

LightSquared is not only demanding changes to FCC regulations detrimental to GPS users everywhere, it also demands that GPS users to bear the burden of mitigating the interference created by its proposed network of 40,000 transmitters.


jjoshua
Premium
join:2001-06-01
Scotch Plains, NJ
kudos:3

All I know is that...

Your average GPS consumer is not going to be happy if their devices stop working correctly.

At which point, the offending towers will be located and probably taken off line.


fifty nine

join:2002-09-25
Sussex, NJ
kudos:2
reply to xenophon

Re: Truth or FUD?

Someone needs to teach you guys (and lightsquared) the concept of a guard band.


fifty nine

join:2002-09-25
Sussex, NJ
kudos:2
reply to xenophon

Re: all I hear is...

The GPS industry is not "bleeding into" anything. Receivers don't bleed.

Lightsquared is trying to fit a slightly oval peg into a round hole. They figure if they hit it hard enough it will go through.

Sammer

join:2005-12-22
Canonsburg, PA
reply to openbox9
said by openbox9:

LightSquared? It seems to be doing the most whining. Maybe like a 2-yr old it hopes that if it cries enough it will get its way.

Of course LightSquared is whining, it bought political influence to get the rules changed in the middle of the game but never counted on all this blowback. The real answer is for those in our government to be a lot more honest, stop selling influence and to stop favoring their political friends. If we didn't have government corruption we wouldn't have problems like Solyndra, LightSquared, etc.

openbox9
Premium
join:2004-01-26
Germany
kudos:2
reply to xenophon
I don't believe GPS receivers are bleeding anything. They're receivers. The problem is that LightSquared's frequencies allocated by the FCC (which is wholly at fault in this situation IMO) interfere with weak signal GPS transmissions that have been in use for decades. A problem didn't exist until the FCC waived use of frequencies intended to be broadcast from thousands of miles away for terrestrial use.


jseymour

join:2009-12-11
Waterford, MI

Hook, Line and Sinker

Gotta love how some people here, who obviously don't understand the first thing about how radio works, are swallowing LightSquared's bull-pucky hook, line and sinker--then turning around and re-spewing it.

Two things, here: As somebody else noted: The RF spectrum doesn't consist of nicely channelized "slots" with the RF equivalent of brick walls between them. Depending upon a variety of factors, closely-located services will interfere with one another. However, in this case, it'd be a one-way street, since LightSquared's transmitters would be terrestrial, and GPS' are way out in space, which brings us to...

Problem the second: LightSquared is trying to re-purpose the allocation they "inherited." It was purposed to space-based transmitters, not earth-based. If they were trying to use it for that for which it was initially allocated, there'd be no problem.

LightSquared needs to bugger-off.

Jim

elefante72

join:2010-12-03
East Amherst, NY
Reviews:
·Verizon FiOS

dont cry for lightsquared

The problem is that the original l-band was meant for MSS, and for those who dont know GPS specifically uses a low-power PRC so that multiple sats can transmit on the same frequency and not "interfere" with each other. The bands that lightsquared for 4GLTE was not designed for terrestrial and this signal is billions of times more powerful than the GPS signals.

These freq are meant for supplementing GPS signals where the sat-based signal cannot penetrate objects, NOT for 4G LTE.

Now there are two different signals L1 (what consumer GPS use) and L2 (high-precision/military). Make no mistake these lightsquared devices will still interfere w/ consumer GPS, however because of the nature of the L2 signal (much harder to track) it will pretty much render them useless.

Now we know that cells are pretty much harmless in planes, but if you have a new lightsquared device on the plane and dont turn it off, you can now interfere w/ the planes GPS. I would call that a problem.

In addition when lightsquared did their tests the "bent" there transmitters lower to the ground than what they would actually need to deploy in the wild, obviously mitigating the actual interference.

Now dont cry for lightsquared, they got this for "free" in an acquisition, so it's not like they are out dollars, and also they havent actually produced any handsets (which would clearly show the problem).

This is yet one of the first situations of the bandwidth wars, and the government needs to step in and protect our GPS frequencies because however today most GPS receivers use L1, many more designs in the future will use L2 with the need for more accurate positioning.

So what lightsquared is trying to do is to reclassify free spectrum they got for 4GLTE when in fact those freq were never meant for it, and now are pushing for the government to give them "free" spectrum worth billions in other bands for nothing.

This is pure corporate squatting, and IMHO lightsquared should go out of business or pay the billions for actual 4G spectrum.

nweaver

join:2010-01-13
Napa, CA
reply to pjcamp

Re: Truth or FUD?

FUD-ish...

GPS satellites, because they are moving pretty darn fast, undergo a large doppler shift. High precision receivers need to be able to see the satellites even when heavily red-shifted.

Since the neighboring bands to the GPS were reserved for satellite to ground communication, this was not a problem as the level of interference from use of the neighboring band would not be a problem.

The problem is, Lightsquared is a ground-based system, with much much much more powerful transmitters than the GPS-neighbors ever expected nor had to deal with.

Its like setting up a high precision watch factory in a ZONED as quiet neighborhood. Then next door someone bribes the planning commission to allow a Disaster Area concert at 1000 decibels, which knocks your precision equipment for a loop...


firephoto
We the people
Premium
join:2003-03-18
Brewster, WA
reply to xenophon
said by xenophon:

Yeah, the GPS industry is at fault here. If they use spectrum they are not allocated to, they obviously either need to fix it or buy the spectrum from LS.

Yea, I mean when those billion dollar military satellites were made I can't believe how they went cheap on the radios which is wrecking havoc on our job creators on the ground trying attract investors with the next generation broadband. . . ... /s

The fact is that this scheming company is using frequencies and bands that might someday totally not be used by gps systems anymore and part of them being able to do this is by not interfering with said systems. Now they come up with some add-on box that doesn't fix the problem it compensates for it, for $400 a whack which I'm sure some of that they pocket for themselves.
--
Say no to JAMS!

PDXPLT

join:2003-12-04
Banks, OR
reply to pjcamp
Yes it's true. They've long sold receivers for years that were susceptable to signals outside the GPS band, even though they were told by the FCC years ago that those bands wouldn't stay vacant for long, and they better prepare for the day when those bands get allocated.

What did the GPS do? Nothing. They stuck their heads in the sand. They continued to sell cheap, poorly designed receivers into the marketplace, even though the FCC told them that in a few years they would be experiencing interference. Unfortunately, receivers don't emit signals, and the regulatory ability to do something about them is limited; e.g., if you want to sell crap receivers, you can. The GPS industry decided they could instead wage a PR war, as that would be the less expensive way to deal with it, and most people don't understand the issue. From the sympathetic reception they've gotten from most places, including this website, it appears to be working.

PDXPLT

join:2003-12-04
Banks, OR
reply to keyboards

Re: all I hear is...

Their "solution" is to force a front end filter on the high precision GPS receivers rather than controlling their own power spectrum AND expect the existing device owners / manufacturers to foot the bill.

Their solution is a reasonable one; i.e., ask the GPS industry to design their receivers to only be sensitive to signals allocated to the GPS band, and filter out signals outside that band. It's feasible, just not as cheap as whining about having to deploy proper equipment instead, or purchasing the spectrum from Lightsquared.