شبیه‌سازی عددی اثر تداخلات آکوستیکی روی اختلاف فاز سنسورهای آکوستیکی

In commercial shotgun microphones, in certain frequency bands, side sounds are eliminated. In common models, the presence of receiver capsules helps to create a phase delay in the incoming waves from around the microphone. In this case, the waves entering from the side walls are out of phase and neutralize each other, and the effect of side sounds is reduced. Due to the presence of receiver capsules, the operation of creating a phase delay is done in analog form and at a specific frequency. But the goal is that the frequencies in which the operation is performed are determined by the operator and within the desired range. This cannot be done by creating receptor capsules. For this purpose, microphones are used instead of receiver capsules, which perform operations digitally and the desired frequencies can be determined through the operator. In addition to the use of microphones instead of receiver capsules that reduce the effects of the side wave field, the existence of networks with specific sizes and distances throughout the blimp will reduce the noise in the received sounds as much as possible. Therefore, these types of microphones together with the blimp not only digitally programmed, lead to the reduction of side wave field effects but also reduce the noise that direct waves can bring with them. In this paper, we use Comsol software and by emitting wave sources, the phase difference between the microphones is calculated, and in the case that only one wave source is in fixed coordinates and intensity it is compared. It is also checked which parameter and in what way leads to nonlinear phase difference and to what extent the error rate is reduced. In addition, the angle and intensity of the second wave source where the phase difference becomes nonlinear is obtained. This simulation has been done in a two-dimensional sample with a blimp. Finally, in different frequencies, the stated analyzes are examined. According to the obtained results, in the pressure range of 0.0002 pascals, little changes are observed in the error range. Also, one of the most suitable angles for placing the second wave source is the angle where the difference between the angle of the first source and the second source is 5 degrees. It can be seen that the lower the intensity of the second source, the higher the frequency, and the error can be controlled and kept constant.