Department of Electroacoustics, Faculty of Electrical Engineering and Computing, University of Zagreb, 10000 Zagreb, Croatia.
Geolux d.o.o., Ljudevita Gaja 62, 10430 Samobor, Croatia.
Sensors (Basel). 2022 Apr 8;22(8):2851. doi: 10.3390/s22082851.
The goal of this paper is to design a broadband acoustic camera using micro-electromechanical system (MEMS) microphones. The paper describes how an optimization of the microphone array has been carried out. Furthermore, the final goal of the described optimization is that the gain in the desired direction and the attenuation of side lobes is maximized at a frequency up to 4 kHz. Throughout the research, various shapes of microphone arrays and their directivity patterns have been considered and analyzed using newly developed algorithms implemented in Matlab. A hemisphere algorithm, genetic algorithm, and genetic square algorithm were used to find the optimal position and number of microphones placed on an acoustic camera. The proposed acoustic camera design uses a large number of microphones for high directional selectivity, while a field programmable gate array system on a chip (FPGA SoC) is selected as the processing element of the system. According to the obtained results, three different acoustic camera prototypes were developed. This paper presents simulations of their characteristics, compares the obtained measurements, and discusses the positive and negative sides of each acoustic camera prototype.
本文旨在设计一种基于微机电系统(MEMS)麦克风的宽带声相机。本文描述了如何对麦克风阵列进行优化。此外,描述的优化的最终目标是在高达 4 kHz 的频率下,在期望方向上的增益和旁瓣衰减最大化。在整个研究过程中,考虑了各种形状的麦克风阵列及其指向性图案,并使用在 Matlab 中实现的新开发算法进行了分析。使用半球算法、遗传算法和遗传方算法来找到放置在声相机上的麦克风的最佳位置和数量。所提出的声相机设计使用大量的麦克风来实现高指向性选择性,而现场可编程门阵列系统芯片(FPGA SoC)则被选为系统的处理元件。根据获得的结果,开发了三个不同的声相机原型。本文介绍了它们的特性仿真,比较了获得的测量结果,并讨论了每个声相机原型的优缺点。