In April 2020, I presented a talk on understanding GPS in contested environments. Topics included the following:Understanding GPS position error, dilution of precision and user range errors, physical and radio visibility, terrain heights and field results, mitigation techniques and alternative navigation technologies.

The national nightmare is over, we have a new president.

We live in the woods here. We are not alone.

I used to write stories. I haven't had the desire to write in quite a while, but I feel it starting to come back. Hopefully these won't be the last ones I'll write.

When you turn on your GPS receiver - what happens? Well, lots of stuff. But primarily, GPS receivers work in a two stage process: 1) Look for available satellites to track 2) Do everything else. In this article, I want to focus on step 1, we'll get to step 2 later.

The day Dr. David Dao was dragged off of a United plane so United employees could get to their next destination was significant for another, possibly longer-lived reason that the sheer brutality it portrayed.