The Research On Vibration Isolation Of Super Low Frequency Magnetic Communication Antenna

The high attenuation of electromagnetic waves by seawater makes it difficult to use commonly used radio wave signals to complete communication tasks.Super-low frequency communication is still an effective means of underwater communications.As a key equipment for underwater communication technologies,super-low frequency magnetic antennas have high sensitivity and Anti-jamming ability,its design level and communication ability can reflect the national military strength.However,there are a large number of noise magnetic fields around the submarine.Motion-induced noise caused by submarine vibration seriously affects the antenna's communication performance.This paper starts with the working principle of ultra-low frequency magnetic antenna,and qualitatively deduces the influence of submarine vibration on the SNR of antenna communication based on the law of electromagnetic induction,and obtains vibration characteristics of super-low frequency magnetic antenna based on ANSYS modal analysis.The results show that it is of great significance to adopt effective vibration isolation measures to reduce the Y-and Z-direction vibration of the antenna for improving the signal-to-noise ratio of communication.Then,the vibration isolation design method is summarized and proposed.According to the working environment of the super-low frequency magnetic antenna and its highly sensitive characteristics,the commonly used vibration isolation technologies are analyzed and compared,and a two-stage passive vibration isolation solution is adopted to complete the research of antenna isolation;and the two layers are separated.Based on the analysis of the influence of the parameters of the vibration system on the basis of the analysis of the characteristics,a system parameter design method was proposed.According to the design results of the vibration isolation parameters,the appropriate vibration isolation elements were selected.After that,according to the principle of decoupling,the reasonable installation and arrangement of vibration isolation elements and the preliminary scheme of the vibration isolation system were established.The three-dimensional model was established and based on ANSYS finite element simulation,the vibration isolation coefficient under harmonic excitation in the communication frequency band was obtained;The vibration isolation performance,the comparison of the simulation results with the theoretical calculation of the two-stage vibration isolation,and the influence of the vibration characteristics of the system on the vibration isolation performance were analyzed.Finally,a prototype of a vibration isolation prototype and an experimental test system were set up.The vertical vibration isolation performance of the prototype was verified based on the national standard of vibration experiment using the frequency sweep experiment.The experimental and simulation results were compared and evaluated.Then Comparing and evaluating the finite element simulation vibration isolation performance before and after its improvement.