Will that GPS equipment of your be rendered useless by Broadband wireless service?
- Steve Martin
- Posts: 632
- Joined: Mon Apr 04, 2005 12:24 pm
- Location: Hayward
FCC asks for more information on Lightsquared & GPS
Steve Martin, LS 7264
- Steve Martin
- Posts: 632
- Joined: Mon Apr 04, 2005 12:24 pm
- Location: Hayward
Difference between Communications Engineers and GPS Engineers
I was browsing thru GPS World magazine at lunch and found an JAVAD ad that had a great simple graphic that illustrates the difference between Communications and GPS signal tracking, and a fundamental reasion why LightSquared Engineers do not understand the potential effects on GPS tracking.
Here is the link: http://javad.com/cgi-bin/jgnss/cgi?Action=PollManager
Page down below Mona Lisa
Here is the link: http://javad.com/cgi-bin/jgnss/cgi?Action=PollManager
Page down below Mona Lisa
Steve Martin, LS 7264
- pls7809
- Posts: 1035
- Joined: Tue Apr 13, 2004 3:48 pm
- Location: Chino, CA
Public notice from the FCC was posted on their website:
http://transition.fcc.gov/Daily_Release ... 1537A1.pdf
http://transition.fcc.gov/Daily_Release ... 1537A1.pdf
Ryan Versteeg, PLS, CFedS
-
Stan_K
- Posts: 79
- Joined: Tue Sep 07, 2004 1:11 pm
- Location: Sacramento
Would someone who reads "bureaucratic lingo" better than I please chime in.
Does this posting imply LightSquared needs to PROVE it will not cause interference with GPS? Or is it just one more hurdle everyone needs to jump through?
The only way that the LightSquared signal will not cause interference is if they significantly reduce the output power. Unfortunately, that would probably make their service unusable.
This is easily tested by keying up a 5 watt 2-way radio (entirely different frequenciy band) while close to your GPS receiver. Watch the satellites drop out!
The LightSquared signal was originally planned for 100,000 watt radiated power. I am guessing our recivers would not work within 1,000' of their transmitters. They wanted to put their transmitters on most cell towers. Think about the cell tower spacing in your area!
Thank you to all who took the time to contact the FCC.
Stan
Does this posting imply LightSquared needs to PROVE it will not cause interference with GPS? Or is it just one more hurdle everyone needs to jump through?
The only way that the LightSquared signal will not cause interference is if they significantly reduce the output power. Unfortunately, that would probably make their service unusable.
This is easily tested by keying up a 5 watt 2-way radio (entirely different frequenciy band) while close to your GPS receiver. Watch the satellites drop out!
The LightSquared signal was originally planned for 100,000 watt radiated power. I am guessing our recivers would not work within 1,000' of their transmitters. They wanted to put their transmitters on most cell towers. Think about the cell tower spacing in your area!
Thank you to all who took the time to contact the FCC.
Stan
Stanley King, CA PLS 8038
- Steve Martin
- Posts: 632
- Joined: Mon Apr 04, 2005 12:24 pm
- Location: Hayward
The way I read it is that the FCC is essentially talking out of both sides of their collective mouth saying that they support wireless broadband service AND that they will protect GPS against harmful interference, while at no time admitting that it erred in approving a waiver to broadcast from cell towers on frequencies allocated to low power Satellite broadcasts (next to GPS frequencies) at a power level Billions of times stronger, virtually guaranteeing interference.
Steve Martin, LS 7264
- pls7809
- Posts: 1035
- Joined: Tue Apr 13, 2004 3:48 pm
- Location: Chino, CA
- pls7809
- Posts: 1035
- Joined: Tue Apr 13, 2004 3:48 pm
- Location: Chino, CA
- Administrator
- Posts: 459
- Joined: Mon Jul 22, 2002 9:55 am
LightSquared: Did White House Pressure General Shelton to Help Donor?
LightSquared: Did White House Pressure General Shelton to Help
Donor? - The Daily Beast
http://www.thedailybeast.com/articles/2 ... did-white-
house-pressure-general-shelton-to-help-donor.html
Donor? - The Daily Beast
http://www.thedailybeast.com/articles/2 ... did-white-
house-pressure-general-shelton-to-help-donor.html
- pls7809
- Posts: 1035
- Joined: Tue Apr 13, 2004 3:48 pm
- Location: Chino, CA
Not that I'm a dedicated follower of Fox News, but the No. 1 article this morning on Foxnews.com is this new article posted yesterday from The Daily Beast.
http://www.foxnews.com/
We need to post some commments in there about the real issues of this story while it's trending...
http://www.foxnews.com/
We need to post some commments in there about the real issues of this story while it's trending...
Ryan Versteeg, PLS, CFedS
- NickL
- Posts: 76
- Joined: Tue Feb 12, 2008 11:42 am
- Location: Portland, OR
- Contact:
http://www.foxnews.com/scitech/2011/09/ ... a-network/
In testimony before the House Armed Services Committee on Thursday, General William Shelton, head of Air Force Space Command, detailed the results of tests from earlier this year intended to quantify the effect of LightSquared's forthcoming network on GPS.
"Aviation receivers operating as far as 7.5 miles from LightSquared transmitters completely lost GPS and were degraded out to distances of more than 16.5 miles," Shelton said. "High precision GPS receivers such as those used for surveying and geological study requiring precise measurements were adversely affected out to 213 miles and totally lost GPS out to 4.8 miles."
In testimony before the House Armed Services Committee on Thursday, General William Shelton, head of Air Force Space Command, detailed the results of tests from earlier this year intended to quantify the effect of LightSquared's forthcoming network on GPS.
"Aviation receivers operating as far as 7.5 miles from LightSquared transmitters completely lost GPS and were degraded out to distances of more than 16.5 miles," Shelton said. "High precision GPS receivers such as those used for surveying and geological study requiring precise measurements were adversely affected out to 213 miles and totally lost GPS out to 4.8 miles."
- pls7809
- Posts: 1035
- Joined: Tue Apr 13, 2004 3:48 pm
- Location: Chino, CA
- NickL
- Posts: 76
- Joined: Tue Feb 12, 2008 11:42 am
- Location: Portland, OR
- Contact:
LightSquared Signs Agreement with Javad GNSS to Develop ‘Interference-Free’ GPS
http://www.pobonline.com/Articles/Indus ... 0001105800
"LightSquared has signed an agreement with Javad GNSS Inc. to develop a system designed to eliminate related interference issues for high-precision GPS devices."
~~
http://www.rpls.com/blogs/1/131
"LightSquared yesterday threw a Hail Mary pass with its announcement that it is working with Javad GNSS Inc. to develop a system that will eliminate interference issues related to high-precision GPS devices. "See, we told you a simple fix was possible!" the company essentially gloated as it spiked the ball in the end zone. Its rivals, high-precision GPS users, are clamoring for a review of the play.
In a flurry of emails following the announcement, surveyors shared their concerns. And in a standing-room-only crowd at the ION GNSS 2011 conference in Portland, Ore., yesterday evening, a panel representing a broad range of manufacturers and users reiterated the negative results from tests that have been conducted so far. "All of them agreed more testing is needed and more time is needed," said Jered McGrath, PLS, survey project manager for MacKay & Sposito Inc. in Vancouver, Wash."
"LightSquared has signed an agreement with Javad GNSS Inc. to develop a system designed to eliminate related interference issues for high-precision GPS devices."
~~
http://www.rpls.com/blogs/1/131
"LightSquared yesterday threw a Hail Mary pass with its announcement that it is working with Javad GNSS Inc. to develop a system that will eliminate interference issues related to high-precision GPS devices. "See, we told you a simple fix was possible!" the company essentially gloated as it spiked the ball in the end zone. Its rivals, high-precision GPS users, are clamoring for a review of the play.
In a flurry of emails following the announcement, surveyors shared their concerns. And in a standing-room-only crowd at the ION GNSS 2011 conference in Portland, Ore., yesterday evening, a panel representing a broad range of manufacturers and users reiterated the negative results from tests that have been conducted so far. "All of them agreed more testing is needed and more time is needed," said Jered McGrath, PLS, survey project manager for MacKay & Sposito Inc. in Vancouver, Wash."
- Steve Martin
- Posts: 632
- Joined: Mon Apr 04, 2005 12:24 pm
- Location: Hayward
LightSquared throws a Hail Mary pass
You do not have the required permissions to view the files attached to this post.
Steve Martin, LS 7264
- Steve Martin
- Posts: 632
- Joined: Mon Apr 04, 2005 12:24 pm
- Location: Hayward
Newspaper ads
Duncan Marshall sent me this pdf of a LightSquared ad in the local paper.
Wow, the hyperbole and gross distortion of statistics and facts.
Wow, the money being thrown at pushing the LightSquared proposal thru before it is properly tested and proven to have no interference with GPS.
Wow, the hyperbole and gross distortion of statistics and facts.
Wow, the money being thrown at pushing the LightSquared proposal thru before it is properly tested and proven to have no interference with GPS.
You do not have the required permissions to view the files attached to this post.
Steve Martin, LS 7264
- Jim Frame
- Posts: 1599
- Joined: Thu Oct 17, 2002 8:52 pm
- Location: Davis, CA
- Contact:
I like the part where it says that precision GPS devices "inappropriately violate our licensed spectrum." The only devices that violate that license are the GPS space vehicle transmitters. The fact that survey-grade receivers depend upon out-of-spectrum frequencies in order to obtain sufficient ranging data isn't a violation of the Lightsquared license, it's merely an unfortunate circumstance. However, it's a circumstance of such magnitude that there's no way Lightsquared should be allowed to get away with its proposal.
The situation is analogous to a prescriptive easement. The FCC knew -- or should have known -- that millions of GPS users were dependent upon very weak signals in and near the GPS frequencies. For it to allow Lightsquared to enforce the technical limits of the spectrum license it bought, with the intention of using that spectrum in a manner inconsistent with its designation (space-based versus ground-based), would be grossly inequitable.
.
The situation is analogous to a prescriptive easement. The FCC knew -- or should have known -- that millions of GPS users were dependent upon very weak signals in and near the GPS frequencies. For it to allow Lightsquared to enforce the technical limits of the spectrum license it bought, with the intention of using that spectrum in a manner inconsistent with its designation (space-based versus ground-based), would be grossly inequitable.
.
- Steve Martin
- Posts: 632
- Joined: Mon Apr 04, 2005 12:24 pm
- Location: Hayward
GPS Coalition responses
Trimble is fighting the good fight for GPS...
You do not have the required permissions to view the files attached to this post.
Steve Martin, LS 7264
- Administrator
- Posts: 459
- Joined: Mon Jul 22, 2002 9:55 am
- Steve Martin
- Posts: 632
- Joined: Mon Apr 04, 2005 12:24 pm
- Location: Hayward
LightSquared does not have the "Legal Right" to Build out in the MSS band
A good article published on American Surveyor online...
http://www.amerisurv.com/content/view/9304/2/
http://www.amerisurv.com/content/view/9304/2/
Steve Martin, LS 7264