Yes, Virginia, There Is No Back-up
Sam Wormley
Yes, Virginia, There Is No Back-up
http://www.gpsworld.com/gnss-system/news/yes-virginia-there-is-no-back-9276?print=1
December 14, 2009
A Wistful Holiday Letter from an Engineer
As I read the title of this month's Survey newsletter column, "As Loran Fades, Attention
Shifts to DGPS and SBAS," it came to my mind that there are many people around the world
who do not recognize the difference between a position, navigation, and time (PNT) system
and an augmentation of a PNT system — a difference that was not clearly pointed out. I
have heard many PNT users expound on how good an augmentation is and, to my amazement, how
the augmentation could provide service despite a GNSS outage. I've stopped being
surprised. After all, I still remember the days when Galileo was being touted as a backup
to GPS.
Unfortunately, the leadership worldwide has become decidingly less technical over the last
decade, and without proper explanation from staffers (who have also become decidingly less
technical), the point is lost.
The simple fact is that augmentations are of little or no use if the system they augment
is unavailable. Perhaps this point should be made, and made loudly and strongly --
particularly in the case of the scheduled termination of Loran. The same holds for the
respective differences between real-time navigation, long-term positioning, and time and
frequency — distinctions, again, that are lost to many. While WAAS, NDGPS, and even
HA-NDGPS are admirable efforts that highlight what a group of talented, dedicated
engineers can do, maybe what we need is a PNT 101 course/flash card set for those
"technically challenged" so they can better understand the ramifications of their
decisions. It took me and millions of others five years to get a Bachelor of Engineering
degree; we cannot expect the leadership to learn engineering overnight.
I remember fondly the times when, as a junior engineer, I had five layers of management
above me that all held engineering degrees. Today I can't go up to any level and find a
single one. What went wrong? I do not know, but I do not think it bodes well for the world.
In any event, best regards to GPS World, and Happy Holidays