Anti-interfering method for environmental foreign bodies for the microstrip antenna sensor

• The antenna cladding is innovatively applied to the microstrip antenna sensor. • Foreign bodies will cause resonant frequency deviations with an order of MHz. • A type of antenna cladding under a marginal convex plate structure is proposed. • Resonant frequency fluctuation level of the sensor with cladding is reduced by 95% As a result of the rapid development of intelligent equipment, the importance of intelligent sensing technology for use in structural health monitoring applications is increasing. Among the emerging intelligent structure monitoring methods, microstrip antenna sensing technology is attracting considerable attention. The working environments for mechanical equipment are often harsh and highly differentiated. Multiple environmental jamming factors, including water, dust, ice, and other foreign bodies, will reduce the parameter monitoring reliability of microstrip antenna sensors. In this paper, an anti-interfering method for these environmental foreign bodies based on antenna cladding technology is presented. First, a multi-physical numerical model is established to study the mechanism by which the environmental foreign bodies affect the resonant frequency of the antenna sensor. The effects of the foreign bodies on the sensor’s resonant frequency are analyzed via simulations. The anti-interfering cladding design method for environmental bodies is then studied. The structure,a shape, and size of the environmental anti-interfering cladding are designed using an FR4 epoxy plate with good heat and moisture resistance, largely causing the fluctuation level of the sensor’s resonant frequency with changes in the environment to be reduced by more than 95%. The simulation and experimental results show that the proposed anti-interfering method for environmental foreign bodies using antenna cladding technology greatly improves the reliability of the microstrip antenna sensor and has considerable engineering application value.