Structural Parametric study on axisymmetric condenser microphone for infrasonic sensitivity

Microphone sensitivity is a characteristic property of microphone which determines the amount of output electrical signal for a given sound pressure level (SPL). Low and ultra low frequency sound wave so called Infrasound carry useful information applicable in geology, aeronautic science and meteorology. Due to the low SPL of infrasound waves, microphone sensitivity is crucial in infrasonic measurement systems. In this study a variety of cases are simulated that vary the membrane radius, membrane young modulus and air-filled gap between membrane and back plate, in 54 combinations. Results of the study shows that air-filled gap has the greatest impact on increasing the microphone sensitivity while the effect of other parameters are ignorable.