Electronic Global Positioning System Jammer Using Software Defined Radios

This article describes the use of a commercial software-defined radio (SDR) to generate an intentional interfering signal for protection against drones. The system aims to counter unauthorized and offensive drone actions. The particular case of the geo-location system is analyzed, where the sensitivity limit to block its operation is measured in two different receivers: an external Stoton module and a Samsung mobile phone, serving as a drone surrogate. The USRP B-210 software-defined radio, controlled by GNU Radio, was employed to generate the jamming signal. The final experiments took place in an outdoor environment, with two different antennas and in two different sites. Results were compared with literature reports as well as a first-order approximation based on the free-space formula (Friis) free-space propagation formula (Friis). A radius of protection of approximately 29 meters was observed by using the radio with a simple omnidirectional monopole antenna, designed and constructed for this test.