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    Re: GPS Interference
    From: Lu Abel
    Date: 2011 Sep 29, 23:09 -0700
    There was a full-page ad by LightSquared in today's edition of Silicon Valley's newspaper, the San Jose Mercury News.

    Starts out with generalities ("everybody wants more mobile bandwidth"), then throws in some out-of-date truths ("we proposed using satellites to provide coverage in remote areas"), claims FCC engineers thoroughly analyzed their proposals (true -- but then the FCC commissioners supposedly ignored the analysis), and ended up with the claim that (my words, not their exact words) "all interference is due to unauthorized use of our spectrum" (I guess that means "gee, if we transmit a signal a billion times stronger than GPS's in a frequency band adjacent to GPS's and your receiver can't filter it out, that's 'unauthorized use of our spectrum'").  

    As someone who has followed this in various technical publications, I was left with a pretty bad taste in my mouth.

    Oh, and a political note -- LightSquared claims they started working on gaining approval for their system in 2004.  So their "efforts" span two very different presidents from two different parties.   It ain't just something to be blamed on the current incumbent.


    From: Gary LaPook <glapook@pacbell.net>
    To: NavList@fer3.com
    Sent: Thursday, September 29, 2011 10:31 AM
    Subject: [NavList] Re: GPS Interference

    But we need accurate GPS coordinates so that we can check the accuracy of our practice CN shots.


    --- On Thu, 9/29/11, Frank Reed <FrankReed@HistoricalAtlas.com> wrote:

    From: Frank Reed <FrankReed@HistoricalAtlas.com>
    Subject: [NavList] Re: GPS Interference
    To: NavList@fer3.com
    Date: Thursday, September 29, 2011, 5:43 AM

    All of this is tainted by politics. Not to say that the AOPA letter isn't honest and genuine, but since the Obama Administration has made itself the "we love trains, we hate planes" Oval Office (and really it's the President himself who has this prejudice), it's tough to separate general aviation's general angst from independent engineering analysis. I notice that the aviation industry's long-standing newspaper of record, "Aviation Week & Space Technology," has been much more circumspect in their concerns over LightSquared, at least AFTER LightSquared agreed to abandon the frequency band closest to GPS frequencies.
    By the way, this is the first time in my experience following NavList messages that a threat to GPS has not been celebrated as a window of opportunity for celestial navigation experts. But times change! :)
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