The whole world is dependent on satellite systems as they are used in almost all fields of economic and social life, in transport, banking, industry, agriculture, etc. Thanks to the development of technology, most smartphones used everyday have been equipped with a built-in GNSS receiver, many cars with navigation systems and all vessels with GNSS receiver or a satellite compass for navigation. Systems working on similar frequencies can be used for jamming or spoofing satellite systems. Such purposeful system jamming can be damaging to users and society as a whole. This article includes a description of jamming and a presentation of one of possible receiver designs allowing for jamming signal detection. This receiver has been designed and built by the authors of the article.
 Figurski M. et al., Influence of interference in GPS measurements, GPS vs. jamming, ‘Geodeta’, 2011, No. 01, pp. 46-51, [online], https://geoforum.pl/upload/review/file/188_s46_51_z.pdf [access 24.08.2016].
 Specht C., System GPS, Publ. Bernardinum, Pelpin 2007.