dagblog - Comments for "Planned wireless Internet network threatens GPS"

From what I read in the

Beetlejuice — Sat, 09 Apr 2011 02:05:03 +0000

From what I read in the article, they're using sat comm frequencies in which GPS occupies and has has always been a sore point for the military...bleed over from comerical products and users. Perhaps the solution would be for the FCC to designate a specific and unique frequency band strictly for a nationwide broadband network isolated so it doesn't interfere with others.

Oh we have the pass-band

cmaukonen — Sat, 09 Apr 2011 01:17:59 +0000

In reply to This is a known issue with

Oh we have the pass-band issue OK. It's the front ends that are the problem. Strong signals can overload them and cause IMD and mixing products which mess things up badly.

This is a known issue with

Beetlejuice — Sat, 09 Apr 2011 00:10:38 +0000

In reply to Planned wireless Internet network threatens GPS

This is a known issue with military contractors providing equipment and services to the US military...everything using the electromagnetic spectrum, especially at or near cell phone frequencies, walking all over each other. The only problem is GPS is King, so everyone else will have to suck hind tit. In other words, the US Military is so dependent upon GPS, there's no alternative. The plain old simple telephone used 3000 Hz for voice with a passband of 500 Hz on either side (4000 Hz total) so as to isolate one subscriber from another...and that didn't always work - many people could pick up crosstalk from those subscribers adjacent to them. Sounds like there are serious issues at the higher frequencies simple passbands aren't capable of isolating effectively. And those higher frequencies are more expensive to effectively engineer solutions that could make the venture too costly to pursue.