Spoofing??? What is this funny sounding word you might think. Spoofing actually belongs under the banner of secretive instead of funny.
Spoofing is disguising the identity of the source. For instance, when you send an message as an anonymous member of some platform, and you mask you unknown status to an identity that the person you contact knows. And in more serious situations might trust. It can be spread in numerous fashions. Think about a simple email, a phone call or even a website that seems harmless.
Jamming is the simple man’s way of disrupting by blocking out all signals frequencies by there choosing. This can already be done by something like a small transmitter. The reason that this can be easily done is because satellite signals are among the weaker signals in general, that also includes background noise. But luckily it is very easy to detect. When somebody jams a signal than you notice that immediately, when that happens everything else shuts down as well. So the problem then is easily found.
Unfortunately a receiver can also be spoofed or jammed. this is done by sending out false transmissions and mask them in such a manner that they appear to be the genuine one’s. And the reason you will see the spoofed signal instead of the genuine one is because the spoofed one is stronger. In a nutshell this means that a receiver that’s logged on to the false signal will think it is somewhere else instead. And the worst part of it is that it is seem relatively easy to implement spoofing, and very hard to detect.
Imagine hours of surveying under a false signal without noticing it. That can be a tremendous setback.
The designers of GNSS and also the manufacturers are aware of these issues. They are working on solutions that can be implemented into the receivers. The solution will discriminate the fake signals from the genuine ones so that your receiver will not be fooled into thinking it is somewhere else.
But always be aware of potential spoofed signals when you are surveying. Otherwise you might can start al over again once you found out the signal was false.
If there is anybody who willing to share his or her spoofing or jamming experience on the forum, feel free to do!
The more everybody gets to know about this the better!