ZHAO Hong-liang（赵洪亮）, TIAN Xiang-e（田祥娥）, FENG Guo-jin（冯国金）, SUN Ke（孙珂）
(College of Information and Electrical Engineering, Shandong University of Science & Technology, Qingdao 266510, China)
Abstract:An audiobeam loudspeaker system based on the fixed-point digital signal processor (DSP) TMS320VC5509A (VC5509A for short) is developed to emit audible sound with high directivity along a selected path. This system is composed of preamplifier, anti-aliasing filter, ADC (analog to digital converter), VC5509A basic system, DAC (digital to analog converter), smoothing filter, ultrasonic power amplifier and ultrasonic transducer array. VC5509A is used to implement the key signal preprocessing algorithms, such as signal preprocessing, amplitude modulation, carrier signal generator,etc. The experiments show that this system has the advantages of high accuracy and good stability.
Key words：parametric loudspeaker; audiobeam; digital signal processor(DSP)
CLD number： TN643 Document code： A
Article ID： 1674-8042(2012)01-0057-05doi： 10.3969/j.issn.1674-8042.2012.01.012
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