Cognitive Noncoherent Jamming Techniques for Frequency Selective Attacks

This paper deals with the design of non-coherent jamming strategies capable of ensuring spectral compatibility with friendly radio frequency (RF) emitters. The goal is achieved via a cognitive approach, which, after recognizing the presence of friendly RF systems within the bandwidth of interest (perception), synthesizes a jamming waveform (action) with spectral notches, that allows to interfere exclusively with opposite emissions. Two methods are proposed for the synthesis of the jamming signal. The former leverages optimization techniques for quadratically constrained quadratic problems (QCQP) where each constraint embeds the interference level tolerable by a specific friendly RF system. The latter is a very computationally efficient approach based on simple projections, allowing a control over the spectral notch positions and widths. At the analysis stage, the performance of the devised jamming techniques is firstly numerically analyzed in terms of spectral occupancy and autocorrelation characteristics. The impact of the quantization process involved in the digital-to-analog conversion (DAC) of the jamming waveforms is also examined, with a particular focus on the spectral shaping impairments resulting from reduced DAC resolution. Finally, waveform transmission and reception is experimentally assessed with software defined radio (SDR) devices.