• Journal of Convergence for Information Technology
• /
• v.10 no.3
• /
• pp.16-21
• /
• 2020

This paper describes the jamming characteristics of a stand-off jammer jamming the LPI radar. The LPI radar reduces the side lobes of the receiving antenna to reduce the effect of jamming. It is easy a radar to predict the effect of jamming on a self-protection jammer where the jammer is in the same position as the target. However, for stand-off jammer jamming at different locations from the target, the prediction of jamming effect is complex. In this paper, the jamming effect of LPI radar is analyzed using signal to jamming ratio and burn-through range. Also, when the antenna's side lobe decreases below -30 dB, the stand-off jamming effect in the side lobe direction is weak. So we proposed a new jamming method for the main lobe and analyzed the jamming effect. This study is expected to be useful for the design and operation of aircraft jammers.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.12 no.6
• /
• pp.906-911
• /
• 2001

In this paper, LPI(low probability of intercept) and AJ(anti jamming) performance of the chirped BPSK system are analyzed. In the chirp method the cyclostationary of the signal is eliminated, since the instantaneous frequency is varied randomly within the whole spread bandwidth. Therefore, chirp method is considered for good LPI system against DAM(delay-and-multiplier) or SC (squaring circuit) interceptor which detects the chip rate or carrier frequency. Longer chirp duration makes the LPI performance better. From the simulation results, the chirp method has better AJ performance than DS(direct sequence) system in the PBNJ(partial band noise jammer) channel. At the same JSR(jammer to signal power ratio) level, chirped BPSK system has more robust AJ performance against MTJ(multi-tone jammer) than PBNJ.