Paper Title
Low-Frequencyacoustic Wave Direction Detection Using Mach-Zehnder Interferometer

Abstract
In this paper, low-frequency (<5 kHz) acoustic wave direction detection method based on Mach-Zehnder interferometer (MZI)is demonstrated. The sensor for direction detection is implemented with two fiber-coiled acoustic sensors including a sound absorption medium between them. The measured amplitude difference depending on the wave directionshowed more than 20 dB over 3.5 to 4.5 kHz. Keywords� Directional detection; acoustic wave sensing; Mach-Zehnder interferometer.