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egorny

The FCC is about to make a decision that will affect the use of GPS all across the US, ours as well as others.

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Just to give everyone an idea of the scope of the issue....

 

We're talking about 40,000 towers positioned worldwide and each could cause a GPS interference area of 3 to 5 mile radius. That covers about 1% of the surface of earth, but this does not account for the vast bodies of water, both poles, and uninhabited areas.

 

Since land only covers about 29% of the globe, and approximately 90% of our population occupies about 3% of the land, most of civilization lives on only about 1% of the land. This 1% of land is the same 1% of the surface of the earth which will have GPS affected since the towers will be placed in the most populated areas.

 

Unfortunately, this is the same area where the majority of geocaches are located. If this goes through, you might as well kiss most urban geocaches goodbye. :( Only the most remote geocaches would be unaffected.

 

medoug.

 

I was re reading this thread, and some of the others... I don't recall reading anything about world wide... only about the US..

where did you see this part. I've said before, there are other regulating bodies that deal with the rest of the world re radio.

 

Anyway, since I'm here... The big problem as I see it is as always this idea of powerful transmitters... The correct action would be to reduce the size and power of the ground transmitters way down... and then increase the numbers... to the point where signal strength is about the same as direct satellite. This is what cellular is accomplishing now compared to the early days... one of the strengths of their system is that it can always be subdivided and equipment recycled to new areas that can use the wider area coverage. There is a strong market for this new tech INDOORS... how much of the real market is inside buildings, even underground.

Cellular early on started using leakyax to provide indoor coverage for buildings for cellular radio telephones. LS has a satellite system for outdoors regardless... and there is nothing like buildings for absorbing signal from escaping (or coming in)... besides which how many GPS users (regardless of the equipment) get a good lock indoors now... so it separates the user base as well.

Filtering of the transmitters can also strongly affect the signal spread... that can be done for NEW GPS as well... but harder for older units, perhaps impossible... Anyone heard from other Countries and International Agencies? I saw several mentioned in the saveourgps site memberlist...

 

Just recommenting...

 

Doug 7rxc

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I was under the impression that LightSquared is planning to use relatively low power units in urban areas operating at 1800 MHz and higher, with an effective range of about a quarter mile. They would be placed on every corner, which would provide less saturation than wirelss G routers in urban areas.

 

The real problem is in rural areas where higher powered units will be deployed. The agricultural equipment manufacturer, John Deere, has compained that it's tests show interference with precision GPS systems used in contour farminf applications.

Edited by GClouse

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I've been actively writing and calling my representatives in Washington about this issue. I'm from a small town in Montana and likely won't be affected, by and large, if Lightsquared towers go online. If I were living in a larger city or metropolis the situation would be alot more dire regarding the prospects if Lightsquared goes online. What would happen to the sport of geocaching in those larger towns? What would you do with your expensive receivers when they are severely trampled on in the big cities?

 

What I'm saying is the possibility of LightSquared going online is there and, if given their way, the GPS manufacturers will be forced to design different units with better filtering. Older units rendered useless. Everyone who owns a GPS right now could essentially throw them in the trash and buy a new.

 

My point is, I feel that there should be alot more noise being generated by users like us. Call and write your Congressman. Call and write your Senator. Don't sit back and wait for your neighbor to do it.

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I've been doing some more reading on this.. and have a new query on a different aspect.

 

I keep reading how their licence was/is originally for space to ground via their satellite... and how they have A satellite in orbit.

 

Since they have apparently only have ONE, it would have to be geosynchronous (fixed relative position)... given the cost of these satellites, I would assume that it's failure would demand immediate replacement. Since I only see 'owned', I also assume that they do own it, but it's possible that it's only 'rented' space of course, or perhaps a shared ownership of a multi user device.

 

Anyway... if there is only one does failure to replace it mean loss of the frequency allocation? The whole terrestrial aspect would seem to be hanging on the space portion of the licence. That is, no space, no terrestrial. What is their 'service' capability if they are spending a fortune developing the ground aspect? I think that has to be addressed. There are others that would use the space licence a bit differently if it were available again. Just another random thought chain.

 

To yogazoo: I think you have the concept a bit backwards based on GClouse's comment... it's the rural areas that will get the more powerful 'area' transceivers... don't forget their proposal is for two way communications... so the users will be transmitting as well on similar frequencies... how much interference will come from the less filtered user devices... Not to mention where are these devices coming from anyway... I don't think it will be current phones / devices... so there is a whole new cost to someone as well.

Those will have to be type certificated as well as the new tranceiver base sites.

 

That will be a whole new line of research for us... what range will the new devices have... no point having long range bases without long range devices... right? All of which seem to be run by a company that has had money problems already with the sat service. One reason they seem to have given for needing the terrestrial service. My money says they are having problems with the satellite already.

 

Doug 7rxc

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To yogazoo: I think you have the concept a bit backwards based on GClouse's comment... it's the rural areas that will get the more powerful 'area' transceivers... don't forget their proposal is for two way communications...

 

Doug 7rxc

 

I keep forgetting this detail however, the only reason, apparant to me, why rural areas would get a higher transmit power is because the towers would be more spread out and the extra power would be needed to cover the gaps. True, us rural folks may experience the same interference but 1)=the signals will be on-par (power wise) with cell signals and there is alot of country in Montana without even basic cell coverage (or extremely weak signals), and 2) City folks will have the same problem, more transmit towers, even at a lower power = similar interference.

 

Either way, the approval of LightSquared's license to operate would drastically change the infrastructure of this country. And you're right, the space to ground frequency they bought originally was never intended to be amplified. This is the main sticking point in my mind. If I was to purchase a GMRS two-way radio which is limited to 5Watts and modified it to run at 10Watts I would be in violation of FCC rules. If a giant corporation with lots of $$ does it, it's OK. Our country is for sale to the highest bidder and public domain is worthless unless it's in the hands of a private entity to make a profit.

 

There's alot of spin coming from the executives at LightSquared. It seems as though whenever a buisness or wireless related media outlet discusses the story, the GPS issue is downplayed severely and/or the GPS industry is somehow equally to blame. The information battle can be lost in this way and public opinion will matter.

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Again I've been reading more and looking around online...

 

Two general things I found... (sorry if they've been here before) I don't remember seeing them, but I have been off and on lately.

 

http://en.wikipedia.org/wiki/LightSquared

 

http://en.wikipedia.org/wiki/Cellular_frequencies

 

The first is a summary of what they are about... probably a bit skewed (there was a neutrality audit or something posted).

The second is just a description of frequency usages... there are some interesting links at the bottom of both.

 

I did learn that LS has two licenced sats... one US and one Canada... and sounds like they hope to bless Canada with the same problems. I'm not sure what will happen there, since they are having their study by the FCC... I have yet to see what if anything is up in Canada with Industry Canada... although we did have some expansion of cell frequencies here recently... mostly that was to encourage coverage in undeveloped (or less desireable -read as profitable) areas... I thought. Also found that there are apparently already phones and devices that can use 1700 and 1800 mhz frequencies in areas around the world for 4G... Anyway, there is lots more to read about it... Seems like they certainly assume that it's a done thing.. I saw their site and it says its fully approved, way back in January or so... so we may be gaining ground in light of recent events. Seems the USAF has always been against it as offered. I did notice that they have been dealing for other spectrum for some of this... with other sat providers... Seem to be trying to to be able to move the terrestrial part away from GPS frequencies, which would help. Think we need the sat only service people to demand the frequencies for sat only projects... since there isn't all that much of it available.

 

Got to run... trying to figure out why my old Garmin 45xl is really bad these days... I was complaining about 11 m EPE... today it was over 30M... I had to reset it... maybe it defaulted to feet... duh! it's possible I guess... the Map60cx was bang on!

 

Always problems and answers..

 

Doug 7rxc

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More condescension from Genachowski. Sounds like a bit of contempt for the GPS community. His tone leads me to believe that current GPS receivers could be in trouble.

 

Genachowski addresses GPS interference.

 

Excerpt from www.feircebroadbandwireless.com:

 

Moreover, Genachowski took a shot at the GPS community: "It should be no surprise to anyone involved in the LightSquared matter that the company was planning for some time to deploy a major terrestrial network in the spectrum adjacent to GPS," he wrote. He noted several FCC orders, including a March 2010 order that allowed Harbinger to control Skyterra (now LightSquared) in which Harbinger explained its plans to construct a network that would cover 90 percent of the U.S. And Genachowski noted that the GPS industry actively participated in proceedings as early as July 2009. In fact, the U.S. GPS Industry Council filed a joint letter with Skyterra agreeing that the GPS interference had been resolved.

Edited by yogazoo

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What this article (and most like it) neglect to cover in depth is the spectrum slight of hand that was requested by LS and nearly rubber stamped by the FCC in the first place. That we may also have a serious issue of interference is SECONDARY to the fact that this spectrum should never have been licensed for terrestrial use in the first place. It was only BECAUSE it should have never been used in this manner that LS got access to it on the cheap as satellite bandwidth to begin with, and puts them in an unfair competitive position IF the FCC continues to let this move forward. It's no wonder that LS's competitors aren't happy, either. The FCC has attempted to hand LS a very large gift at our expense.

 

So while there certainly remains cause for concern over the interference issue, focus needs to continue on the bogus method by which LS obtained this spectrum for terrestrial use in the first place. Go back to those earlier financial/political articles cited, and keep your congresscritters riled up out there.

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Anyone else chomping at the bit for the final report, scheduled for tomorrow?

 

Although, given the stakes involved, I'll bet one donut LightSquared doesn't transmit the report until 4:59 pm ET, and it'll be a couple days before it makes it's way to the interwebs.

 

Here's my anty. :omnomnom:

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Given the reports that have already trickled out, no suprises are expected. Lightsquared's transmissions have a profound impact on GPS reception. We already know what the tests have shown, the real news will be where we go from here. That will be the interesting, and potentially disastrous news.

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I haven't read through this entire thread, but are you saying that geocaching will soon end? :(

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I hate seeing corporations step on the rules like this and get away with it. They literally took a portion of the band and, in direct violation of the FCC rules and the intended purpose of the band, they took it for their own purposes for profit.

 

I know I will not buy into their service if it slams my GPS and the FCC offers no recourse. I just hope they realize that they are the interloper in the L1 band, and their repeaters are terra-based. It seems fairly obvious to me that the repeater units can easily be "taken off line" if there is a group effort to make it happen. What happens if some concerned citizens just keep disconnecting their repeater antennas? At what point is it no longer financially feasible to operate their data network in the L1 band?

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It's really in the hands of our bought-off politicians at this point. The FCC seems to be able to do what it wants. If you combine that with politicians whose campaigns are paid by these very corporations, you have a situation where the idea of the "public good" no longer exists. I don't mean to start a political discussion, both sides of the isle are just as guilty. I'm simply stating that it wouldn't suprise me if GPS is held partly accountable for the interference given the condition of Washington political culture.

 

In short, yes, geocaching could take a hit. Will it? I'm doubtful given the push-back against Lightsquared but don't bet the farm (pun intended for those in the know). Call your senator or representative and voice your opinion.

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Yogazoo -

 

But the folks from camp Peary aren't, ahem, supposed to be operating where LightSquared operates. Perhaps you meant those guys at Quantico?

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I'm trying to decide what to make of this comment by LS:

 

“Among the main reasons for the slight delay has been that based on preliminary test results, LightSquared determined that additional testing, beyond what had been planned initially, including alternative frequency plans to support its network roll-out..."

 

One wonders if "alternative frequency plans" simply means that LS would consider operating in only the lower portion of the available space, as far below L1 as possible, and try to avoid interference that way. In fact, if one could attribute that level of cunning to LS, one could imagine that this whole flap about GPS interference was only a way for LS to say, "OK, we'll be good citizens and confine ourselves to the low end of the available spectrum" all as a way to misdirect attention away from the fact that they did a bait and switch with the FCC to get access to that spectrum to begin with, providing them with an unfair competitive advantage (cheap bandwidth).

 

However they try to sugar coat use in the upper region closer to L1, it sounds as though that is going to be shot down.

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I'm trying to decide what to make of this comment by LS:

 

“Among the main reasons for the slight delay has been that based on preliminary test results, LightSquared determined that additional testing, beyond what had been planned initially, including alternative frequency plans to support its network roll-out..."

 

One wonders if "alternative frequency plans" simply means that LS would consider operating in only the lower portion of the available space, as far below L1 as possible, and try to avoid interference that way. In fact, if one could attribute that level of cunning to LS, one could imagine that this whole flap about GPS interference was only a way for LS to say, "OK, we'll be good citizens and confine ourselves to the low end of the available spectrum" all as a way to misdirect attention away from the fact that they did a bait and switch with the FCC to get access to that spectrum to begin with, providing them with an unfair competitive advantage (cheap bandwidth).

 

However they try to sugar coat use in the upper region closer to L1, it sounds as though that is going to be shot down.

 

Given that they are partnering up with others and trying to arrange other access to other bands through those deals, I'd say they are planning on using their sats to downlink to the new stations and someone elses allocation away from the GPS for the terrestrial network... thus the dealing. That would be a much better arrangement anyway... same for the uplink frequencies to the sats.

There hasn't been any problems with their sat ops has there? It's mostly the way they do business that's the problem.

And the fact that they couldn't do it with just their frequencies... but then they are a service wholesaler, not a provider for users...

 

Doug 7rxc

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Given that they are partnering up with others and trying to arrange other access to other bands through those deals, I'd say they are planning on using their sats to downlink to the new stations and someone elses allocation away from the GPS for the terrestrial network... thus the dealing. That would be a much better arrangement anyway... same for the uplink frequencies to the sats.

There hasn't been any problems with their sat ops has there? It's mostly the way they do business that's the problem.

And the fact that they couldn't do it with just their frequencies... but then they are a service wholesaler, not a provider for users...

 

Doug 7rxc

 

I think you may be right on this view. They may end up just using this new band space for "Listening" and not "transmitting". At least for transmissions that will not bleed into GPS. My brother worked for one of the major cell companies as a cell tower tech. I did a ride along with him once. The complexity of the switching the systems do is mind boggling. He used to have a small receiver in his truck. I asked him what it does. He said you can actually hear cell conversations with it. We turned it on. I thought that he meant you could eavesdrop on conversations. :) What I heard coming out of the receiver was about the most garbled up mess you ever tried to listen to. Two words in one conversation, then another voice and one word, then another voice. He explained that the the switches in the tower did this to maximize loads/service/bands. Your 2 minute conversation with your wife sounds clear to you on the phone, but it's been sliced, diced and extruded in ways most of us can't fathom.

 

The reason I mention this is because as crowded as the cell bands are now, if alternatives for "recieving" could be cast to another area, then I can't see why other providers wouldn't find it valuable.

Edited by Woodstramp

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While we're waiting, is anyone able to find the actual extension request?

 

LightSquared's request for an extension until July 1 came from Jeff Carlisle, the company’s vice-president for regulatory affairs and public policy, who wrote in a June 15 letter to the FCC...

 

Just idle curiosity if there's any other details that don't fit into a press release...

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Update:

 

Sprint Nextel corp and LightSquared, Inc. have just reached a 15-year deal to provide high-speed LTE services, equipment, and share expansion costs, according to Bloomberg. All the details haven't been announced, but according to insiders the deal could be valued as high as $20 billion. From a letter from LightSquared financial backer Phillip Falcone to Harbinger Capital Partner investors obtained by Bloomberg:

 

LightSquared and Sprint will jointly develop, deploy and operate LightSquared’s 4G LTE network. Sprint will become a significant customer of LightSquared’s 4G LTE network.

 

We have no idea how this will affect any relationship between Sprint and Clearwire (which ain't exactly the greatest in the world), but we can tell you that your current

Sprint 4G phones won't stop working until long after the contract is up. If Bloomberg is right on this one (and they usually are), expect a formal announcement soonish.

 

 

 

That ain't good.....

 

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That ain't good.....

Sure isn't if your Sprint options are already under water (and I'd guess almost all of them are for the average Sprint employee). Think it's time to short that puppy. If they're depending upon this new LS spectrum for their 4G rollout, this could get ugly.

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That idea sounds vaguely familiar... now if they got another player to provide terrestrial frequencies for the tower links... they will have something worthwhile...

 

Anyone on a cell that uses the same band as the GPSr's now... not the frequencies specifically... but the range... I know there are some in existence... Wondering about the radiotelephone generated signals effect on a GPS... especially on themselves while in 'pure' GPS mode. That is still going to perhaps be a problem... They might drown out the signals they want to use, unless the phone mode can be turned off independently and completely including the tracking link/data channel (or whatever it's called officially, command channel?) I think that may be an argument for different terrestrial frequencies for 4g users..

 

Doug 7rxc

Edited by 7rxc

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Chalk this one up to blind squirrels and all:

 

LightSquared's request for extension. Didn't see anything there that hasn't already been reported, but it was worth a shot.

 

AND, what appears to be a catalog of all correspondence regarding this proposal.

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OK, here it is, in all its glory. Also, the Inside GPS site has another article about the FCC inviting public comment on the report. This would be a GREAT TIME for everyone to share a cogent thought or two about the original conditional permit, and the remedies suggested. Just saying! ;)

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I like lightsquareds response, "just put a filter on the gps receiver." That definitely helps the millions of devices already in service.

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I like lightsquareds response, "just put a filter on the gps receiver." That definitely helps the millions of devices already in service.

 

which, will feed on the Micro$oft mentality, Simple fix... Since the older equipment no-longer meets Compatibility requirements, You will need to recycle (read Destroy) your old equipment, and spend massive $$$ to purchase new compatible and control regulated equipment.

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DA 11-1133

June 30, 2011

 

COMMENT DEADLINES ESTABLISHED REGARDING THE LIGHTSQUARED TECHNICAL WORKING GROUP REPORT

 

IB Docket No. 11-109

 

Comment Date: July 30, 2011

Reply Comment Date: August 15, 2011

 

On June 30, 2011, LightSquared Subsidiary LLC (LightSquared) submitted a final report of the technical working group co-chaired by LightSquared and the United States Global Positioning System (GPS) Industry Council (USGIC) and organized in response to a condition in FCC Order and Authorization, DA 11-133 (released January 26, 2011). The condition required that LightSquared help organize and participate in a technical working group “that brings LightSquared and the GPS community together” to address potential interference issues recently raised by members of the GPS community. The Order “envision[ed] a working group in which cooperative and candid discussions can ensue, and where information, including proprietary information, can be shared among the participants with appropriate measures in place to protect the confidentiality of that information.” The condition required submission of a final report that includes the working group’s analyses of the potential for overload interference to GPS devices from LightSquared’s terrestrial network of base stations, technical and operational steps to avoid any such interference, and specific recommendations going forward to mitigate potential interference to GPS devices. Among other things, the Order also made clear that, “as a condition of granting this waiver, the [working group] process . . . addressing the interference concerns regarding GPS must be completed to the Commission’s satisfaction before LightSquared commences offering commercial service pursuant to this waiver on its L-band MSS frequencies.”

The technical working group effort identified significant technical issues related to potential LightSquared operations in the upper portion of the L-Band, which is most proximate to the band used by GPS. Over more than three months, the technical working group tested more than 130 representative devices in seven different receiver categories, in a number of different test environments. The tests demonstrated potentially significant interference between LightSquared operations in the upper portion of the band and various GPS receivers. The tests also identified some interference issues in the lower 10 MHz portion of the band. The overall conclusion of the testing is that transmissions in the upper 10 MHz channel — the channel nearest to the 1559-1610 MHz GPS band — will adversely affect the performance of a significant number of legacy GPS receivers.

In addition to the technical working group report, LightSquared has submitted its recommendations to address the problems identified by the working group. In particular, LightSquared indicates its willingness to: (1) operate at lower power than permitted by its existing FCC authorization; (2) agree to a “standstill” in the terrestrial use of its Upper 10 MHz frequencies immediately adjacent to the GPS band; and (3) commence terrestrial commercial operations only on the lower 10 MHz portion of its spectrum and to coordinate and share the cost of underwriting a workable solution for the small number of legacy precision measurement devices that may be at risk. We specifically invite comment on these recommendations, including any alternative proposals to enable these two important services – GPS devices and L-band mobile broadband – to co-exist. We also welcome comments on the technical working group report generally. Comments should be filed no later than July 30, 2011, and reply comments by August 15, 2011.

Comments and Reply Comments. Comments and reply comments may be filed using: (1) the Commission’s Electronic Comment Filing System (ECFS); or (2) by filing paper copies. All filings should reference the docket number of this proceeding, IB Docket No. 11-109.

 Electronic Filers: Comments may be filed electronically using the Internet by accessing the ECFS: http://fjallfoss.fcc.gov/ecfs2/. Filers should follow the instructions provided on the website for submitting comments. In completing the transmittal screen, ECFS filers should include their full name, U.S. Postal Service mailing address, and IB Docket No. 11-109.

 

 Paper Filers: Parties that choose to file by paper must file an original and one copy of each filing. Filings can be sent by hand or messenger delivery, by commercial overnight courier, or by first class or overnight U.S. Postal Service mail. All filings must be addressed to the Commission’s Secretary, Office of the Secretary, Federal Communications Commission.

 

 All hand-delivered or messenger-delivered paper filings for the Commission’s Secretary must be delivered to FCC Headquarters at 445 12th St., SW, Room TW-A325, Washington, DC 20554. The filing hours are 8:00 a.m. to 7:00 p.m. All hand deliveries must be held together with rubber bands or fasteners. Any envelopes or boxes must be disposed of before entering the building.

 

 Commercial overnight mail (other than U.S. Postal Service Express Mail and Priority Mail) must be sent to 9300 East Hampton Drive, Capitol Heights, MD 20743.

 

 U.S. Postal Service first-class, Express, and Priority mail must be addressed to 445 12th Street, SW, Washington DC 20554.

 

Accessibility Information. To request materials in accessible formats for people with disabilities (Braille, large print, electronic files, audio format), send an e-mail to fcc504@fcc.gov or call the Consumer & Governmental Affairs Bureau at (202) 418-0530 (voice), (202) 418-0432 (TTY).

 

The comments and reply comments filed in response to this Public Notice will be available via ECFS at: http://fjallfoss.fcc.gov/ecfs2/; you may search by docket number (IB Docket No. 11-109). Comments and reply comments are also available for public inspection and copying during business hours in the FCC Reference Information Center, Portals II, 445 12th Street S.W., Room CY-A257, Washington, D.C. 20554. Copies may also be purchased from Best Copy and Printing, Inc., telephone (800) 378-3160, facsimile (202) 488-5563, e-mail FCC@BCPIWEB.com.

Ex Parte Rules. This proceeding shall be treated as a “permit-but-disclose” proceeding in accordance with the Commission’s ex parte rules. Persons making ex parte presentations must file a copy of any written presentation or a memorandum summarizing any oral presentation within two business days after the presentation (unless a different deadline applicable to the Sunshine period applies). Persons making oral ex parte presentations are reminded that memoranda summarizing the presentation must: (1) list all persons attending or otherwise participating in the meeting at which the ex parte presentation was made; and (2) summarize all data presented and arguments made during the presentation. If the presentation consisted in whole or in part of the presentation of data or arguments already reflected in the presenter’s written comments, memoranda or other filings in the proceeding, the presenter may provide citations to such data or arguments in his or her prior comments, memoranda, or other filings (specifying the relevant page and/or paragraph numbers where such data or arguments can be found) in lieu of summarizing them in the memorandum. Documents shown or given to Commission staff during ex parte meetings are deemed to be written ex parte presentations and must be filed consistent with section 1.1206(B) of the Commission’s rules. In proceedings governed by section 1.49(f) of the rules or for which the Commission has made available a method of electronic filing, written ex parte presentations and memoranda summarizing oral ex parte presentations, and all attachments thereto, must be filed through the electronic comment filing system available for that proceeding, and must be filed in their native format (e.g., .doc, .xml, .ppt, searchable .pdf). Participants in this proceeding should familiarize themselves with the Commission’s ex parte rules.

By the Chief, International Bureau

 

– FCC –

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LightSquared breaking out the big guns. Hires ex-senator Byron Dorgan for lobbying campaign. Dorgan's sellout comes as no suprise. These guys in D.C., both serving and former, democrat and republican, can't wait to sell us down the river for a buck. I hope the huge PR campaign by LightSquared falls flat but as we all know, money trumps all in DC.

 

What's that word I'm thinking of? I think in the old days they called them women of ill-repute.

 

http://www.lightsquared.com/press-room/press-releases/lightsquared-forms-rural-initiative-to-ensure-lightsquared-and-gps-co-existence/

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Yoga,

 

I've only read where LS will be partnered with Sprint so far. In the link you posted it looks like part of the spin efforr is directed to 'rural' concerns.

 

The other day I saw an ATT comercial where ATT was announcing vast network improvemnets to bring in "50 million new rural" customers. (I assume bolstered ground tower network) I find this curious. Especially, coming from Sprint's competition. I'm wondering if ATT "knows something is afoot" and are engaging to counter this LS thing before it goes online. Kind of like they already know the rails have been greased for LS/Sprint.

Edited by Woodstramp

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I dont see how this can possibly go down , the police and fire departments use GPS to get to locations alone will be enough to ensure this wont disrupt service, so either this isnt as big a deal as it sounds, or it wont happen. There is no chance they will let anything mess with emergency services.

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If the necessary people in Congress receive the necessary graft and corruption payments, anything can be made to happen there.

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If the necessary people in Congress receive the necessary graft and corruption payments, anything can be made to happen there.

 

Truth! I'll echo Michaelnel's comments. Our government officials (both parties) are bought by monied interests and are subsequentially beholden to those interests. Money corrupts policy. Benefit of the masses be darned. What previously seemed obsurd now is within the realm of possibility. That's why, no matter how obsurd this may sound, it is a real possibility and we can't just sit on our haunches.

 

Given the fortunate congressional pushback against GPS interference it's painfully clear that Lightsquared didn't put enough green grease on the skids. Had they donated enough money to various campains the story could easily be in their favor.

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I guess this is the "official" thread. I was posting under topic Lightsquared jamming GPS signals and the thread was closed. Basically my minor nitpick is that Lightspeed is not jamming the GPS band and Garmin's problem is that their filters are not sharp enough(the sides of the filter curve are not vertical enough) to knock down adjacent powerful frequencies. I know the filters aren't strong enough for non-adjacent frequencies because my Garmin fails near TV or cell towers. Band-pass filter

 

If anyone sees articles that are more technical, please post a link.

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I guess this is the "official" thread. I was posting under topic Lightsquared jamming GPS signals and the thread was closed. Basically my minor nitpick is that Lightspeed is not jamming the GPS band and Garmin's problem is that their filters are not sharp enough(the sides of the filter curve are not vertical enough) to knock down adjacent powerful frequencies. I know the filters aren't strong enough for non-adjacent frequencies because my Garmin fails near TV or cell towers. Band-pass filter

 

If anyone sees articles that are more technical, please post a link.

Page 2 of this thread has a host of links to the various Working Group reports, Op/Eds, and other second- or third-hand reports of the whole testing process. And BTW, its not just Garmin having troubles with GPS signal reception, its all of them.

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Re: michaelnel, yogazoo, John E Cache

This is less an issue of filters and more an issue of misuse of the band. This band is reserved for space to ground communication, while the FCC improperly granted a waiver for LightSquared to use it for ground to ground transmission. GPS transmitters emit 22 watts from more than 20,000 km away. LightSquared’s transmitters will emit 15,000 watts from less than 10 km away. GPS receivers already have both resonant cavity and SAW filters; what else could you add? The published literature suggests that no filter capable of protecting GPS receivers from LightSquared’s emissions exists even in concept or design.

 

Not to take sides but this is even more an issue of payoffs to administration officials and a certain political party than to Congress. In fact, the only official push-back has come from some members of Congress. FYI, the FCC is part of the Obama administration. According to the National Legal and Policy Center, LightSquared principals visited the White House and made maximum donations to the Democratic National Committee and the Democratic Senatorial Campaign Committee, and to certain FCC officials' campaign funds. Then, Obama appointees in the FCC circumvented established regulations and procedures.

 

Though unpleasant, these facts are part of the public record. Anyone interested can look it all up.

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I guess this is the "official" thread. I was posting under topic Lightsquared jamming GPS signals and the thread was closed. Basically my minor nitpick is that Lightspeed is not jamming the GPS band and Garmin's problem is that their filters are not sharp enough(the sides of the filter curve are not vertical enough) to knock down adjacent powerful frequencies. I know the filters aren't strong enough for non-adjacent frequencies because my Garmin fails near TV or cell towers. Band-pass filter

 

If anyone sees articles that are more technical, please post a link.

 

The problem is not simply a receiver not filtering out adjacent frequencies. The real problem is that LightSquared is using a terrestrial system for a frequency spectrum which was intended for a space-based system. I would expect Garmin and other manufacturers to filter out adjacent frequencies of a reasonable amplitude, but in this case LightSquared's signal is more than an order of magnitude stronger the GPS signal.

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Not to take sides but this is even more an issue of payoffs to administration officials and a certain political party than to Congress. In fact, the only official push-back has come from some members of Congress. FYI, the FCC is part of the Obama administration. According to the National Legal and Policy Center, LightSquared principals visited the White House and made maximum donations to the Democratic National Committee and the Democratic Senatorial Campaign Committee, and to certain FCC officials' campaign funds. Then, Obama appointees in the FCC circumvented established regulations and procedures.

 

Though unpleasant, these facts are part of the public record. Anyone interested can look it all up.

 

In this case the facts above are true. Not only that but Byron Dorgan (D-ND) has received donations and now lobby's for LightSquared. I'm speaking toward the larger public policy debate. Regardless of party affiliation, 99% of Washington politicians serve the best interest of whomever lines their pockets the most. The influence that has on policy is that policy is taylored to benefit those who can afford to have a voice. The rest of us are left out. This issue is far from over. Watch for LightSquared to ramp up lobbying efforts as I'm sure Falcone knows how Washington works.

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Garmin's problem is that their filters are not sharp enough(the sides of the filter curve are not vertical enough) to knock down adjacent powerful frequencies. I know the filters aren't strong enough for non-adjacent frequencies because my Garmin fails near TV or cell towers. Band-pass filter

Reading that article should be enough to show you that bandpass filtering does not come for free.

 

you should also know that it is physically impossible for Lightwave to keep all their power at their assigned frequency; some will inevitably leak to adjacent frequencies.

 

Regardless of modifications to the GPS hardware presently in use, the Lightsquared towers will cause GPS interference. It's physics.

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Not to take sides but this is even more an issue of payoffs to administration officials and a certain political party than to Congress. In fact, the only official push-back has come from some members of Congress. FYI, the FCC is part of the Obama administration. According to the National Legal and Policy Center, LightSquared principals visited the White House and made maximum donations to the Democratic National Committee and the Democratic Senatorial Campaign Committee, and to certain FCC officials' campaign funds. Then, Obama appointees in the FCC circumvented established regulations and procedures.

 

Though unpleasant, these facts are part of the public record. Anyone interested can look it all up.

 

In this case the facts above are true. Not only that but Byron Dorgan (D-ND) has received donations and now lobby's for LightSquared. I'm speaking toward the larger public policy debate. Regardless of party affiliation, 99% of Washington politicians serve the best interest of whomever lines their pockets the most. The influence that has on policy is that policy is taylored to benefit those who can afford to have a voice. The rest of us are left out. This issue is far from over. Watch for LightSquared to ramp up lobbying efforts as I'm sure Falcone knows how Washington works.

At the risk of bringing any more politics into this (admitting that politics are fully in play)...

 

IIRC, one of the big players in the recent debt ceiling debate made a post-agreement statement that, among other things, one of the sources of "new income" that is supposed to help "balance" the US budget in coming years is the Govt's efforts to "sell broadband frequencies". Can't remember which of the crooks officials actually said it, and my Google-foo is failing me in trying to find the exact quote, but I distinctly remember it, and remember the name "LightSquared" popping into my mind at that moment.

 

Yes, the FCC is an Agency of the current Administration, and so are DoD, FAA, and a host of others that have signed into this issue. Let's hope (and send letters to those involved) that reasonable minds will prevail. BTW, anybody know the price of a frequency??

 

(OK, I laughed at that last bit too, but still.....)

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Garmin's problem is that their filters are not sharp enough(the sides of the filter curve are not vertical enough) to knock down adjacent powerful frequencies. I know the filters aren't strong enough for non-adjacent frequencies because my Garmin fails near TV or cell towers. Band-pass filter

Reading that article should be enough to show you that bandpass filtering does not come for free.

 

you should also know that it is physically impossible for Lightwave to keep all their power at their assigned frequency; some will inevitably leak to adjacent frequencies.

 

Regardless of modifications to the GPS hardware presently in use, the Lightsquared towers will cause GPS interference. It's physics.

In the frequency domain transmitter noise is generated on multiples of the frequency(harmonics) you don't bleed over into adjacent frequencies. The first harmonic is twice the frequency, for example. The FCC has very specific rules on the transmission on unwanted frequencies. I have had to sit over a spectrum analyzer in the radio quiet north woods tracking down noise sources in computer systems so they would pass FCC qualification. Your bold type doesn't sway me and like I said I would prefer a tech doc.

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Garmin's problem is that their filters are not sharp enough(the sides of the filter curve are not vertical enough) to knock down adjacent powerful frequencies. I know the filters aren't strong enough for non-adjacent frequencies because my Garmin fails near TV or cell towers. Band-pass filter

Reading that article should be enough to show you that bandpass filtering does not come for free.

 

you should also know that it is physically impossible for Lightwave to keep all their power at their assigned frequency; some will inevitably leak to adjacent frequencies.

 

Regardless of modifications to the GPS hardware presently in use, the Lightsquared towers will cause GPS interference. It's physics.

In the frequency domain transmitter noise is generated on multiples of the frequency(harmonics) you don't bleed over into adjacent frequencies. The first harmonic is twice the frequency, for example. The FCC has very specific rules on the transmission on unwanted frequencies. I have had to sit over a spectrum analyzer in the radio quiet north woods tracking down noise sources in computer systems so they would pass FCC qualification. Your bold type doesn't sway me and like I said I would prefer a tech doc.

Here's the Working Group's final report. It wasn't too far up the page from here. It may not be Journal Quality, but it is the final report required by the FCC's conditional waiver, and discusses the interference issues.

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In the frequency domain transmitter noise is generated on multiples of the frequency(harmonics) you don't bleed over into adjacent frequencies. The first harmonic is twice the frequency, for example. The FCC has very specific rules on the transmission on unwanted frequencies.

Forget harmonics - that's not the issue. It's a much simpler matter of absolutely SWAMPING the front end of a GPS receiver with, as was noted by one of the most terse and accurate posts on this subject, above, several orders of magnitude more power than any of the GPS manufacturers should have EVER had to expect in the adjacent band.

 

As I suggested much earlier - take a simple AM radio, tune it to 800KHz, then park a megawatt transmitter down the street on 810MHz. You begin to sense the extent of the issue.

 

So let's give it another name or two - High Q adjacent channel rejection isn't free. High Q selectivity isn't free. Are we good with that?

 

I have had to sit over a spectrum analyzer in the radio quiet north woods tracking down noise sources in computer systems so they would pass FCC qualification. Your bold type doesn't sway me and like I said I would prefer a tech doc.

I've likely spent as much or more time dealing with EMI issues in my career, but fully appreciate your time spent in open field testing. But that's not what is at issue here. Turn it around a second - the FCC could give a rip about susceptibility testing. On the other hand, if you want to run a full CE compliance test, you worry over having your equipment hammered with strong fields.

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In the frequency domain transmitter noise is generated on multiples of the frequency(harmonics) you don't bleed over into adjacent frequencies. The first harmonic is twice the frequency, for example. The FCC has very specific rules on the transmission on unwanted frequencies.

Forget harmonics - that's not the issue.
You missed my point entirely. Only harmonics can be generated and they do not fall in the adjacent band. So there is no GPS interference. Like you, I was trying to tell someone to forget the bleeding into adjacent frequencies interference. I also pointed out that the band pass filter is swamped in my other post. I am glad another EMI guy agrees with me.

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