“Backups on backups on backups” – Prof Todd Humphreys at Joint Nav Conference

August 30, 2021

Written by Editor

Image:  “Fortunately” written and illustrated by Remi Charlip

Normally presentations at the ION Joint Navigation Conference are not releasable to the public.

We were very pleased that the very first presentation we attended on the first day was by our friend, the renown Todd Humphreys, from the Univ. of Texas at Austin. And that the presentation was releasable!

His was a great talk, of course. And it had lessons for everyone age 5 and above.

One of his themes was that the news for GPS and GNSS is always a combination of good and bad. GPS is freely available, but it can be easily jammed and spoofed. We can add  coded info to the signal for security, but then there is meaconing.

Just like the children’s book “Fortunately” where the character oscillates between good things and bad things happening. He goes on an airplane ride, but the motor fails, he has a parachute, but it has a hole in it. (We ran out and bought a copy to read to our granddaughters.  Highly recommended.)

So for PNT, says Todd, we need “backups on backups on backups.”

For the more sophisticated he discussed detection of GPS jammers on Earth from space, and displayed a whole lot of equations that, we are sure lots of folks in the room lapped right up, but are far beyond our understanding.

Fortunately his presentation is releasable to the public so you can see his slides by clicking the below.

Unfortunately his excellent narration is not included.

Fortunately, if you attended the conference, it will be included in the proceedings that will be distributed.

 

 

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