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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.

xenophon

join:2007-09-17

2 edits
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.


fifty nine

join:2002-09-25
Sussex, NJ
kudos:2
reply to xenophon
Someone needs to teach you guys (and lightsquared) the concept of a guard band.

nweaver

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

sparc

join:2006-05-06
reply to openbox9
have the government pay 1/3, have the gps industry pay 1/3, and have lightsquared pay 1/3.

problem solved and everyone pays for their portion of the mess.


asdfdfdfdfdf

@myvzw.com
reply to nweaver
I understand what you are saying but surely the question of who is allocated this spectrum matters. The problem, it seems to me, is not that lightsquared has moved into spectrum allocated to gps but that gps is relying upon spectrum assets that were not allocated to it. If this is correct then why is it unreasonable to expect the gps market to shoulder the burden of dealing with it, or at least to be willing to work with lightsquared rather than trying to kill lightsquared's plans.


mix

join:2002-03-19
Utica, MI
reply to xenophon
The idea of the GPS industry "using" spectrum is what irks me. GPS receivers are receive only. They are only listening to signals broadcast to them. Apparently listening to signals outside the allotted GPS bands that the GPS satellites broadcast on has some sort of positive effect if you are looking for high accuracy, high precession results from very low power signals coming from orbit. Go figure.

ConstantineM

join:2011-09-02
San Jose, CA
reply to PDXPLT

FCC Class B Notice: "must accept any interference received&

Wait, what do you mean that FCC couldn't do anything about crappy receivers? Lemme quote something that most people should be very familiar with reading:

«
FCC Class B Notice

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:

1. This device may not cause harmful interference.

2. This device must accept any interference received, including interference that may cause undesired operation.
»
(from »download.oracle.com/docs/cd/E193···ate.html)

Does the second part not actually mean anything?

C.

sonicmerlin

join:2009-05-24
Cleveland, OH
kudos:1
reply to openbox9

Re: Truth or FUD?

said by openbox9:

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.

Give T-Mobile's spectrum to Lightsquared.


r81984
Fair and Balanced
Premium
join:2001-11-14
Katy, TX
Reviews:
·row44
reply to pjcamp
said by pjcamp :

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.

NOPE.
GPS is owned and operated by the US citizens who pay taxes. We pay manufactures to make GPS equipment so we can use our own paid for GPS network. Lightsquared is trying to screw Americans out of their tax dollar investments.

Because of the laws of physics the signal from moving satellites will red shift into the spectrum lightsquared wants to use. There is no fix for this that any GPS manufacture can do.
Even lightsquared cannot fix this and that is why they are trying to get just use the lower 10 mhz spectrum as if they use the entire 59 mhz they wanted to use they would completely jam GPS.

Lightsquare leased satellite only frequency then after the fact they tried to convert it to ground base use. Lightsquare needs to stop what they are doing/stopping trying to screw over america.
--
...brought to you by Carl's Jr.


r81984
Fair and Balanced
Premium
join:2001-11-14
Katy, TX
Reviews:
·row44

1 recommendation

reply to sparc
There is no mess.
Lightsquare leased satellite only spectrum. After they leased it they tried to convert it to ground base us as ground base use is way more valuable than satellite only.

Unfortunately for them it will jam GPS, so they must go back to their original plan for satellite broadband. They took a huge gamble and lost. The GPS industry owes nothing and the Government owes nothing.

FYI, GPS was paid for by US tax payers. We own GPS.
Lightsquare is trying to screw all americans out of our investment.
--
...brought to you by Carl's Jr.


r81984
Fair and Balanced
Premium
join:2001-11-14
Katy, TX
Reviews:
·row44
reply to mix
said by mix:

The idea of the GPS industry "using" spectrum is what irks me. GPS receivers are receive only. They are only listening to signals broadcast to them. Apparently listening to signals outside the allotted GPS bands that the GPS satellites broadcast on has some sort of positive effect if you are looking for high accuracy, high precession results from very low power signals coming from orbit. Go figure.

The laws of physics causes signals from moving satellites to red shift into 25 mhz of the specturm lightsquare will want to use. That is the laws of physics.
GPS receivers will listen for that red shift signals.
If lightsquare trys to use more powerful ground transmitters on those frequencies they will block the red shifted GPS signals and your GPS will not see those satellites.

People use the spectrum not the GPS industry. US tax payers paid for the GPS network over the years since the 70s. We own GPS. Will lightsquared pays us all back for that investment??
--
...brought to you by Carl's Jr.


r81984
Fair and Balanced
Premium
join:2001-11-14
Katy, TX
Reviews:
·row44
reply to asdfdfdfdfdf
The specturm lightsquare is trying to use was allocated for satellite only so GPS did not need a buffer. That spectrum was mainly used for Satellite phones. Other weak satellites will not jam GPS.

Lightsquare leased the satellite only spectrum and after the fact they are trying to convert it to ground base use as ground based use is much more valuable.
Unfortunately the satellite only spectrum if use for more powerful ground transmitters will block the weak GPS satellite signals.
Lightsquared took a gamble and lost.
--
...brought to you by Carl's Jr.


r81984
Fair and Balanced
Premium
join:2001-11-14
Katy, TX
Reviews:
·row44
reply to PDXPLT
Sorry but the bands we are talking about were use by other satellites and even satellite phones.
Other sateillite use will not jam GPS so no buffer was needed.
GPS signals red shift 25 mhz into the specturm lightquared wants to use. That is the laws of physics and nothing can change that. Lightsquared was well aware of this limitation before they leased it.
Lightsquared leased the satellite only spectrum to offer sateillte broadband, they are changing their plan after the fact to try and use ground transmitters as they will make them much more money than satellite broadband.
They took a gamble and lost.

There is nothing the GPS industry can do.
Also all US taxpayers OWN GPS not the GPS industry.
We have been paying for GPS since the 70s. Lightsquare is trying to screw the US out of our investment.
--
...brought to you by Carl's Jr.

openbox9
Premium
join:2004-01-26
Germany
kudos:2
reply to sonicmerlin
I assume you mean following its potential acquisition by AT&T?


asdfdfdfdfdf

@myvzw.com
reply to r81984
And this transformation has been happening over a period of at least 5 years and with government support hasn't it? It isn't like lightsquared just suddenly took it upon itself to alter it's behavior and throw in terrestrial usage. It also isn't as if there wasn't quite a window in which the gps industry had opportunity to plan for this eventuality.
I still don't understand why the gps industry believes that it should have an eternal ability to dictate uses of spectrum that was never allocated to it. Shouldn't there be some responsibility on the part of the gps industry to shoulder some of the burden given that we are talking about spectrum that isn't allocated to gps in the first place?


asdfdfdfdfdf

@myvzw.com
reply to nweaver
"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..."

There is one big problem with your analogy, besides the implication that the lightsquared deal involves corruption, bribery and something sinister and it is this:

A 1000 decibel concert is going to create noise within the factory owned area. In other words, the concert is impinging on the property that the factory owns and impacting the factory's use of its own property. But lightsquared isn't impinging on gps allocated spectrum. It is staying within its own allocated spectrum. A more accurate analogy would be if the watch factory had built part of its factory on a neighbors property that the watch factory didn't own and then, when the neighbor wanted to build on his property, the factory tried to stop it because it would interfere with the factory's use of property that didn't belong to the factory. Lightsquared is not going into gps allocated spectrum and interfering with it. Gps systems are using spectrum outside of what was allocated to them and they don't want anything to happen that will hinder their use of that spectrum, even though it doesn't belong to them.

I understand your argument about zoning but zoning of property near yours can change. You may not like it and that is understandable but you can't rely on the assumption that all the land around yours will remain unchanged and zoned the same way forever. The gps business has had many years knowing this day would come and that they couldn't rely on use of this spectrum outside of their allocation forever.

RokHed

join:2000-09-09
Pennsville, NJ
Reviews:
·Comcast
reply to sparc
Why should LS pay anything to use the spectrum that they already bought? Seems like if GPS followed the rules this wouldnt even be at issue. Why should the government pay anything? Just because you didnt get caught breaking the rules dosnt make you less at fault when you eventually do. This is squarely on the GPS industry and rather than fixing THEIR problem they spend money they could use to bitch about LS. I use GPS and its very useful to me. Its neither my or LS fault and neither should pay to fix it!

Ulmo

join:2005-09-22
Aptos, CA
reply to mix
Right. Physics is what the FCC ought to be paying attention to, not two-bit lawyers that want to ignore physics.

As a single-digit-year-old child, I knew that radio transmissions had harmonics above and below them. Also, satellite is a more delicate and technically particular use of radio. For some poop-eating lawyer to come along and say that property lines are black and white with those types of physics realities, is just absurd.

Ulmo

join:2005-09-22
Aptos, CA
reply to asdfdfdfdfdf
said by asdfdfdfdfdf :

I understand what you are saying but surely the question of who is allocated this spectrum matters. The problem, it seems to me, is not that lightsquared has moved into spectrum allocated to gps but that gps is relying upon spectrum assets that were not allocated to it.

That is not correct.

Lightsquared has moved into spectrum that is not allocated to Lightsquared, i.e., the spectrum is allocated to satellite to ground use, not ground to ground use, and the spectrum on the ground is for satellite to ground use.

Look at Microwave point to point spectrum. It has a physical vector, i.e., a direction of transmission. You aren't allowed to use spectrum Milky-Way wide; a spectrum allocation has necessary LOCATION and STRENGTH components. You CANNOT ignore this, as physics dictates these realities, and the FCC has allocated per this reality. There are almost no world-wide spectrum allocations, and extremely few USA-wide allocations, but my point is more that a spectrum allocation has necessary LOCATION, DIRECTION, and STRENGTH components. Thus to look only at FREQUENCY is bogus.

Furthermore, as others have pointed out, the satellite use of the GPS spectrum INCLUDES Doppler-shifted transmissions, which are OK as a satellite-to-ground transmission to be found in the expected location due to the shift, i.e., somewhat different than the transmission bands allocated. This was known at the time of allocation, and it was also known that this is OK because of the type of lack of interference that neighboring satellite to ground spectrum would cause, and because that is how that spectrum and transmission method works.

The bad thing happened when Lightsquared tried to use spectrum that was not allocated to them, i.e., ground to ground spectrum that interferes with the GPS signals. You cannot argue with Physics, and the FCC used to understand that very well. Anybody currently in the FCC who ignores physics with the GPS system is liable to be munched with this fiasco, and anybody trying to pretend that location, direction, and strength do not matter can have their wives and children ground up in meat grinders for all I care.

Ulmo

join:2005-09-22
Aptos, CA
reply to asdfdfdfdfdf
said by asdfdfdfdfdf :

And this transformation has been happening over a period of at least 5 years and with government support hasn't it? It isn't like lightsquared just suddenly took it upon itself to alter it's behavior and throw in terrestrial usage. It also isn't as if there wasn't quite a window in which the gps industry had opportunity to plan for this eventuality.
I still don't understand why the gps industry believes that it should have an eternal ability to dictate uses of spectrum that was never allocated to it.

They (GPS industry, i.e., us people) aren't using spectrum not allocated to them. They are using spectrum allocated to them, i.e., the obvious resultant doppler-shifted reception of GPS satellite transmissions. That is the way spectrum works. Your concept that this is not theirs because you want to wave magic pixy dust around and ignore physics is just bogus. Everyone knew in the scientific and allocation field of this spectrum that this is the way it works, and that was how to use it, and therefore that is their spectrum, and it's been that way ever since the spectrum was allocated. Your claim that this is not their spectrum is bogus.

Ulmo

join:2005-09-22
Aptos, CA
reply to asdfdfdfdfdf
said by asdfdfdfdfdf :

"
A 1000 decibel concert is going to create noise within the factory owned area. In other words, the concert is impinging on the property that the factory owns and impacting the factory's use of its own property. But lightsquared isn't impinging on gps allocated spectrum. It is staying within its own allocated spectrum.

Incorrect. The GPS spectrum includes all the doppler-shifted satellite-to-ground frequencies. The Lightsquared spectrum does not, as originally allocated, include the ground-to-ground spectrum that they want to use, nor the doppler-shifted satellite transmission area in the reception zone, until FCC got corrupted with this.