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| reply to nweaver
Re: Truth or FUD? 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. | |
 r81984Fair and BalancedPremium
join:2001-11-14
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| 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.
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| 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? | |
Ulmo
join:2005-09-22
San Jose, 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
San Jose, 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. | |
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