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In order to study the electrostatic discharge (ESD) electromagnetic pulse (EMP) to effect mechanism of bipolar junction transistors, systematic ESD injection experiments have been carried on high-frequency low-power transistors, such as 3DG81C, by using ESD model of the human body. Based on the software of Medici, the simulation model of bipolar transistor was established. Through simulation analysis, it is found that the most sensitive port of this kind of devices to ESD is CB junction. Through failure analysis of the devices, the electromagnetic damage mechanism of this kind of transistor is thermal damage which was caused by the thermal secondary breakdown, and the failure modes of transistor are electrical parameter drift, short circuit and functional failure.

At present, methods of bit error rate (BER) analysis for frequency-hopping (FH) system can only solve the problem of barrage jamming, but these are no comprehensive means to follower jamming (FJ). This paper proposes a method of BER analysis with FJ based on frequency hopping M-ary frequency-shift keying (FH/MFSK) system. Through the analysis of the mechanism of FH/MFSK system, assuming the wireless channel is an AWGN channel, the BER formulas for different jamming types are derived, respectively, from the point of one-dimensional probability density function of the output signal of the envelope detector, while judgment principle of envelope detecting method is used. Results show that the BER of multiple FH/MFSK system with FJ is relatively lower. In the worst case of FJ, the BER of FH/4FSK system and FH/8FSK system is reduced by 2 dB and 3 dB, respectively, compared with that of FH/2FSK system. The method of BER analysis proposed provides an effective means to research the BER with FJ in depth.

The technical difficulty of antifollower jamming in communication systems is a wide concern in the peer. In order to solve the problem of difficulty to achieve antifollower jamming, a new identification method of follower jamming is proposed in this paper based on the characteristics of it and then follower jamming is cancelled out. A hardware-in-the-loop simulation platform is built by using FPGA. Then, experimental verification for mitigating performance of follower jamming is conducted based on the platform and the proposed method. Results show that signal-interference ratio (SIR) promotion is different for different jamming frequencies and the jamming mitigation performance is affected by interference intensity. The average SIR promotion can reach 10 dB when variance of jamming signal is between 0.75 and 1.5. In other cases, average SIR promotion is less than 10 dB. The proposed suppression method provides a useful way to antifollower jamming in frequency hopping (FH) communication.