'Facts and Engineering' to Settle LightSquared's Fate: FCC
"Durr.... what's a guard band?" - Julius
The FCC today said that it does not approve of this "guard band" idea, as it leaves too much spectrum unused.
There are two ways to fix this problem. Period.
1) Replace all the cheap, shoddy, accepting-out-of-band-transmissions-as-legiti mate-signals GPS receivers in the world.
2) Increase the guard band size so that cheapskates like Garmin, TomTom and Trimble can keep their lousy second rate radios functioning in the midst of an L-Band LTE rollout.
How crazy is this? "We won't let LightSquared use any of their spectrum unless they can use all of it!"
But an FCC official speaking at a background briefing for the press said creating such a "guard band" between LightSquared's airwav...
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So are you saying that the avionics for RNP/RNAV are lousy, second rate radios too?
GPS receivers are designed to reject strong out of band signals (such as jamming attempts), but the position quality will go down due to this. Sometimes this is acceptable (ie, google latitude showing a general area vs. me inside the bar), but other times this is not...ie..50 foot decision height, which will eventually turn into autoland in the next 10 years. Autolanding on trees would be bad, although, it depends on the size of the tree/if there was a runway after the tree/etc
We are talking weak signal operation here, right next to a powerful transmitter. Its hard to pick up -165dBm signals and process out multipath with some big 100 watt EIRP (o...
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GPS receivers are designed to reject strong out of band signals (such as jamming attempts), but the position quality will go down due to this. Sometimes this is acceptable (ie, google latitude showing a general area vs. me inside the bar), but other times this is not...ie..50 foot decision height, which will eventually turn into autoland in the next 10 years. Autolanding on trees would be bad, although, it depends on the size of the tree/if there was a runway after the tree/etc
We are talking weak signal operation here, right next to a powerful transmitter. Its hard to pick up -165dBm signals and process out multipath with some big 100 watt EIRP (o...
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Replace all the cheap, shoddy, accepting-out-of-band-transmissions-as-legiti mate-signals GPS receivers in the world.
I can only disagree with cautious reservation, as I am not an expert on GPS systems, but I have seen it mentioned in multiple locations that blocking undesired frequencies in GPS receivers is not something that is easy to do without also degrading the real signal. I did a brief googling of that subject when Lightsquared claimed that the problem would go away with a few cents worth of parts, which tickled my skeptic senses.
If all of that is true, I would much rather preserve the on-edge abilities of GPS receivers (particularly where they must be extremely small so we can have e911 phones) than ...
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This forum is closed.
