NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Do We Still Need to Use Sextants?
From: Richard B. Langley
Date: 2013 Apr 6, 09:37 -0300
From: Richard B. Langley
Date: 2013 Apr 6, 09:37 -0300
On 2013-04-05, at 5:48 PM, Frank Reed wrote: > Does anybody know if "dual band" GNSS jammers already exist? Can nefarious no-goodniks already take out GPS and GLONASS at the same time? I assume the technology is so similar that this is the case. But again, I'm just guessing here. Some jammers cover both the L1 and L2 bands. If the jamming signals are broad enough, they will also jam GLONASS. See my GPS World Innovation column for January 2012 for some details on "commercial" jammers: http://www.gpsworld.com/gnss-systeminnovation-know-your-enemy-12475/ By the way, spoofing of GPS signals is more insidious than jamming. > -FER > > PS: Or we could place the sensors above the weather! We position very high-altitude drones with GPS and celestial backup every hundred miles or so along major coasts. They report their positions with higher power signals that are difficult to jam. Then ships below could triangulate off that. Another possibility is to bring back Loran-C, which is far more difficult to jam. The Europeans are doing that with eLoran. See, for example, http://www.gpsworld.com/making-europes-seaways-safe-for-enavigation/ And there is a good overview of GNSS (= global navigation satellite systems, the generic term that includes GPS, GLONASS, Galileo, BeiDou, etc.) security here: http://www.gpsworld.com/directions-2013-the-future-of-gnss-security/ -- Richard Langley ----------------------------------------------------------------------------- | Richard B. Langley E-mail: lang@unb.ca | | Geodetic Research Laboratory Web: http://www.unb.ca/GGE/ | | Dept. of Geodesy and Geomatics Engineering Phone: +1 506 453-5142 | | University of New Brunswick Fax: +1 506 453-4943 | | Fredericton, N.B., Canada E3B 5A3 | | Fredericton? Where's that? See: http://www.fredericton.ca/ | -----------------------------------------------------------------------------
