Usage of repeater jamming techniques for the unmanned aerial vehicle self-protection electronic warfare system againts frequency agile radars

Military use of unmanned aerial vehicles (UAV) along with the other remote missile attack options are increased in recent global conflicts. Fighting against uncrewed systems, which can be used for dirty tasks, is challenging. Being able to remotely control or autonomously programmable gives more opportunity to take risk for unmanned systems. Radars comprise the first stage of any integrated air defense system; electronic warfare becomes more critical to prevent attacks of new type of threats. UAVs can be an effective tool for jamming radar signals. Integrating UAVs in a supportive operation capacity alongside piloted fighters has become crucial to modern military tactics. In this study, we investigate the radars' readiness for these task forces and the jamming performance of the UAVs against the improved radar detection capabilities. Based on that, a monostatic pulsed radar has been modelled using stepped frequency and stepped chirp frequency waveforms with an unpredictable frequency hopping pattern between the coherent sub-pulses. Also, this radar has capability to set the pulse repetition intervals (DTAs) on a pulse-to-pulse as linear or non-linear sequences. An onboard self-protection electronic warfare system is used as a jammer source. To apply the suitable jamming technique according to collected signal characteristics and direction in accordance with the repeater concept, a phased array antennas and central control computer unit is designed. To determine the efficiency of the jammer system, simulations generated using frequency agile radar. The results of simulated test cases have been analyzed in time and frequency domain. Jamming to signal ratios have been obtained to be used as performance metric.