Fuzzy logic decision based on learning, automatic interference elimination method and harmonic radar

Abstract

The invention discloses fuzzy logic decision based on learning and an automatic interference elimination harmonic radar. A mode of two transmitting terminals and one receiving terminal is adopted. A transmitter transmits combined waves and frequencies are f1 and f2. Two transmitting antennas are used to transmit pulse signals. A non-linear target reradiates and reflects an echo to a receiver. Thereceiver adopts one receiving antenna to carry out time sharing receiving. After being amplified, the received echo carries out frequency mixing with 2f1, 2f2 and f1+f2 so as to acquire three second harmonics f21, f22 and f23. At third harmonics, mixed frequencies are 3f1, 3f2, and 2f1+f2, and a fusion center is entered into and the fuzzy logic decision is performed. In the invention, three detectors in the second harmonics and the third harmonics are fused and decided, automatic interference elimination is performed on a learning state, a background is learnt, and during normal work, based onthe three detectors, the fuzzy logic decision is performed on the membership of the "signaled " and the "nonsignaled" of a target. Good detection sensitivity can be provided, a false alarm probability is improved, and good robustness in non-uniform background detection is possessed.

Description

technical field [0001] The invention relates to the technical field of radar in the electronic industry, in particular to a learning-based fuzzy logic judgment and interference automatic elimination method and a harmonic radar. Background technique [0002] Harmonic radar is an effective detection device in security inspection, which can quickly detect and locate various electronic equipment and devices hidden in walls, floors, ceilings, and furniture, including radio stations, bugs, electronic fuzes, and timed explosives , mines, etc. In recent years, with the gradual miniaturization and diversification of smart electronic devices, the detection of illegal electronic devices has become very difficult, and the security work has become more difficult, which has received great attention at home and abroad. [0003] The existing harmonic radar technology mainly uses one frequency or multiple single frequencies to transmit, and only one detector is used to detect nonlinear targ...

AI Technical Summary

Problems solved by technology

However, the miniaturization of electronic equipment and the shielding of electronic equipment have caused the following problems in the actual use of traditional harmonic radars: 1) The probability of missing alarms in detection increases, and the reradiation energy of miniaturized electronic equipment is reduced. Wave radar is difficult to detect tiny electronic targets with existing sensitivity

2) Poor anti-interference ability

When a traditional harmonic radar detects a signal, it processes the received signal and makes a binary judgment of "signal" and "no signal". When there is an interference signal, especially in an environment with a non-uniform background, the probability of false alarm detection increases. , it is difficult to distinguish between interference targets and useful targets

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