GPS signal jammer are used in battlefield applications

The recent reports out of Syria highlight the inclusion of these in an evolving battlespace. One of the simplest threats to drones is the blocking or scrambling its reception of a signal from a GPS satellite. This “GPS jamming” can produce serious operational impact on military mission and will likely become more and more prevalent. According to a piece by NBC, Russians are using GPS jamming against the U.S. military’s smaller surveillance aircraft.

The Systems Tool Kit (STK) has a quick tutorial that demonstrates how to determine if a small, hand-held GPS jammer can interfere with your mission. One can also determine how spectrum filters or phased array adaptive nulling can counter this, or design new systems as other phenomenologies to get positioning, such as celestial navigation, that operate in these denied environment.

The concern comes as civilian aviation and communications systems have repeatedly been jammed in connection with nearby Russian military activities.

The situation was similarly serious in September 2017, when airliners from companies SAS and Widerøe in periods had to navigate with the help of radio signals due to loss of GPS when they entered the East Finnmark airspace. The jamming coincided with the major Russian military exercise «Zapad».

WiFi signal jammer are easy to buy

The GPS signal jammer works by sending out its own signal on the same frequency as the GPS unit, a noisy signal that prevents it from receiving or transmitting any useful information, either in bursts of sound or a continuous wave. 

The fact that GPS cell phone jammer can be bought openly on the internet shows that most countries are prepared to live with the problem. Currently, in internet, it is very easy to find not only jamming but also spoofing equipment available for buying. These equipments are not so expensive, being available in any quantity that one needs. Besides, a several number of tutorials can be found on websites and YouTube, teaching how to spoof and jam vectors, especially drones. It is just to "google it" and one finds security experts raising alarm over how to hack drones

Jamming is defined as "the emission of radio frequency with enough power and with the features needed to prevent, in a given area, the receivers to track GPS signals"

The low power that GPS signals arrives to the receivers allows the power of the jammer to be effective even at very low power levels, making interference in GPS relatively simple and inexpensive to carry out. Various jamming methods are available in the market, being possible to find very efficient ones for $ 1,000.00, which are capable of delivering at least 100 watts (Rrol 2003).

When evaluating the influence of a jammer on a receiver, one should use the J/S relationship (jamming/signal). When expressed in dB, it is the difference between the power of the interfering signal and power of the received one.

https://forum.perfectjammer.com/discussion/122/where-to-buy-a-gps-jammer

https://forum.perfectjammer.com/discussion/132/how-to-block-drone-signals