A new oversampling-based full-duplex radar jamming method with a single antenna

With the fast development of jamming technology, strong coherent jamming based on digital radio frequency memory (DRFM) technology poses serious threats to radar detection capabilities due to their flexibility and deception characteristics. However, the extremely high isolation between transmitter and receiver is difficult to implement in practice, and jammers typically operate in a transmit/receive time-sharing mode. Consequently, the duty cycle of jamming signal received by radar is less than 100% in the time domain, enabling the radar systems to detect targets amidst jamming. To generate a full duty cycle jamming signal, a new oversampling-based full-duplex DRFM jamming generation method is proposed in the transmit/receive time-sharing mode. This method requires that the intercepting width of jammer must be less than the reciprocal of value which is the product of forwarding times incremented by one and the radar signal bandwidth. Therefore, the jammer first intercepts extremely short segments from the radar signal using oversampling, with lengths measured in nanoseconds. Then, the jammer rapidly re-modulates and re-transmits the intercepted signal segments within the corresponding interception period. The jamming signal is filtered by the radar receiver. Then, the spectrum of the signal only contains the complete fundamental component, and the pulse width of the signal matches that of the transmitted signal, achieving a duty cycle of 100% and realizing the full-duplex jamming effect. In addition, the frequency modulation technique is utilized to generate dense false targets corresponding to the transmitted signal, thereby improving jamming efficiency. This paper elucidates the generation mechanism and ramifications of the jamming signal through rigorous signal analysis, delineating the relationship between intercepting length and full-duplex radar jamming generation across various DRFM jamming styles. Finally, the efficacy of full-duplex jamming is substantiated through theoretical analysis and simulation.