Rejection of active interference

Institution of Engineering and Technology eBooks1993pp. 443–514

Abstract

This chapter deals with the rejection of active interference (jamming) in the space domain (antennas) and in the frequency domain, as well as with the simultaneous rejection of clutter and jamming. It is well known that the most effective measure of electronic countermeasures (ECM) is active noise jamming. Therefore, this chapter discusses the rejection of active interference as a main topic of radar electronic counter-countermeasures (ECCM). The strategy of active interference rejection prevents the interference from entering the radar detector as far as possible. Since there are many nonlinear components in the radar receiver, such as mixer, envelope detector etc., a weak signal will be suppressed by the strong interference in these nonlinear components. Therefore, the most effective measures to reject interference are spatial selectivity and frequency selectivity, since spatial selectivity rejects the interference at the antenna, and frequency selectivity rejects the interference before the mixer. Two types of jamming are often used: standoff jamming (SOJ) and self-screening jamming (SSJ). SOJ interferes with the radar receiver mainly through the sidelobe of the radar antenna, while SSJ interferes with the radar receiver mainly through the main lobe of the antenna. It is evident that the best way to reject SOJ is by spatial selectivity, and the best way to reject SSJ is by frequency selectivity. Therefore these two methods are discussed in detail in this chapter.

Related Papers

→ SAR active-decoys jamming based on DRFM(2007)25 cited
Micro Motion Modulation-Based Intermissive Sampling and Repeating Jamming Method(2011)
→ Development of Bandwidth Controlled Noise Jamming Technique for Phase Sampling DRFM(2011)1 cited
Research on Smart Noise Jamming against PD Radar(2011)
Deceptive Jamming and Anti-jamming Based on DRFM(2010)