The Study On Microwave Coupling Into Slot On A Cavity With A Block Inside

There are mainly two approaches for microwave to enter a system, namely, the"front-door"coupling and the"back-door"coupling. The study on coupling of the microwave into a system is the key problem to understand the system effects and the anti-HPM system-hardening technology. This thesis studies the slot coupling process and the effects of the cavity and the inner blocks on the coupling process.The linear coupling of microwave into a vacuum cavity with a slot is simulated at the beginning of this thesis. The resonant effect is verified, and the results show that the reflection of the cavity has little influence on the resonant effect. The numerical computation method is used to study the microwave coupling into slot on a cavity with a block inside. The following conclusions are obtained.1. While the incident microwave is gauss-modulated, the resonant effect does exist in the cavity with slot. The internal block in the cavity has little influence on the resonant effect, all the energy in the cavity is determined by the resonant effect.2. While the frequency of the incident microwave is getting closer to the frequency at which the resonant effect appears, the electric field in the middle of the slot is group delayed. If the condition of resonant is well satisfied, the electric field generated by a single microwave pulse is enhanced rapidly to the maximum value in the middle of the slot, then the value of the electric field attenuates slowly. On the other hand, the E-field generated by multiple microwave pulses will superpose several times before it reaches the maximum value.3. For a given size cavity with a given size slot, the microwave power coupled into the cavity will reach the maximum value while the length of metal block is at a certain value under the condition of resonance. The reason for the emergence of this phenomenon is that the frequency of incident microwave is getting close to the eigenfrequency of the cavity. The position and conductivity of internal metal block have little influence on the coupling of microwave into the slot of the cavity.4. The maximum value of E-field changes periodically with the change of the length of the slot. With the increase of the width of the slot, the E-field in the middle of the slot will decrease gradually, while the power in it increase gradually, the E-field and peak power in the cavity will also increase gradually.