为了有效放大小孔径阵列接收信号间的时间差，提高其定位能力，设计了一个多输入多输出的时延放大系统.首先，对生物耦合结构的二自由度力学模型进行了高维扩展，并对耦合参数与时延放大的关系进行了深入研究；然后，基于高维耦合的力学模型，通过算法的形式实现了一个多输入多输出的时延放大系统，系统参数可根据声源频率进行灵活地调节，从而精确地控制时延放大倍数.实验结果表明：该系统可用于实现小孔径阵列接收信号间的时延放大，改善其定位精度.
In order to magnify time delays between received signals of small aperture arrays and improve the localization performance of such arrays, a multiple-input-multiple-output (MIMO) delay magnification system is presented. The mechanical model of the coupled ears is extended to be n-dimensional. Besides, the relationship between coupling parameters and magnification is investigated. Based on the mechanical model, a MIMO delay magnification system is proposed and realized by algorithm. System parameters can be adjusted flexibly according to sound frequency, and the magnification factor can be precisely controlled. Experimental results show that the delay magnification system can be applied to small aperture arrays to magnify the time delay of received signals and improve the sound source localization accuracy.
［1］ZHANG X, HUANG J C, SONG E L, et al. Design of small MEMS microphone array systems for direction finding of outdoors moving vehicles［J］. Sensors, 2014, 14(3): 4384-4398.
［2］TIETE J, DOMNGUEZ F, SILVA B, et al. SoundCompass: A distributed MEMS microphone array-based sensor for sound source localization［J］. Sensors, 2014, 14(2): 1918-1949.
［3］XU X Y, BAO M, JIA H. A biomimetic coupled circuit based microphone array inspired by the fly Ormia ochracea［J］. The Journal of the Acoustical Society of America, 2017, 141(5): 3649.
［4］MASON A C, OSHINSKY M L, HOY R R. Hyperacute directional hearing in a microscale auditory system［J］. Nature, 2001, 410(6829): 686-690.
［5］MILES R N, ROBERT D, HOY R R. Mechanically coupled ears for directional hearing in the parasitoid fly Ormia ochracea［J］. The Journal of the Acoustical Society of America, 1995, 98(6): 3059-3070.
［6］MILES R N, CUI W L, SU Q T, et al. A MEMS low-noise sound pressure gradient microphone with capacitive sensing［J］. Journal of Microelectromechanical Systems, 2015, 24(1): 241-248.
［7］MILES R N. Acoustically coupled microphone arrays［J］. Journal of Vibration and Acoustics, 2016, 138(6): 064503.
［8］KUNTZMAN M L, HEWA-KASAKARAGE N N, ROCHA A, et al. Micromachined in-plane pressure-gradient piezoelectric microphones［J］. IEEE Sensors Journal, 2015, 15(3): 1347-1357.
［9］HALL N A, KUNTZMAN M, KIM D. A biologically inspired piezoelectric microphone［J］. The Journal of the Acoustical Society of America, 2017, 141(5): 3794.
［10］LIU H J, CURRANO L, GEE D, et al. Understanding and mimicking the dual optimality of the fly ear［J］. Scientific Reports, 2013, 3: 2489.
［11］WILMOTT D, ALVES F, KARUNASIRI G. Bio-inspired miniature direction finding acoustic sensor［J］. Scientific Reports, 2016, 6: 29957.
［12］WILMOTT D, ALVES F, KARUNASIRI G. High sensitive MEMS directional sound sensor with comb finger capacitor electronic readout［J］. The Journal of the Acoustical Society of America, 2015, 138(3): 1768.
［13］MASOUMI A R, GHAEMI K, BEHDAD N. A two-element biomimetic antenna array with enhanced angular resolution and optimized power extraction［J］. IEEE Transactions on Antennas and Propagation, 2015, 63(3): 1059-1066.
［14］XU H P, XU X Y, JIA H, et al. A biomimetic coupled circuit based microphone array for sound source localization［J］. The Journal of the Acoustical Society of America, 2015, 138(3): 270-275.
［15］王庆生, 饶柱石, 塔娜. 微型仿生声定位结构的设计及定位方法的研究［J］. 振动与冲击, 2010, 29(4): 122-129.
WANG Qingsheng, RAO Zhushi, TA Na. Mechanism of a mini-instrument for sound source localization［J］. Journal of Vibration and Shock, 2010, 29(4): 122-129.
［16］YANG M, ZHU X L, ZHANG Y Q, et al. Parameter study of time-delay magnification in a biologically inspired, mechanically coupled acoustic sensor array［J］. The Journal of the Acoustical Society of America, 2016, 140(5): 3854-3861.
［17］ZHU X L, YANG M, ZHANG Y Q, et al. Study of response difference amplification and bionic coupled circuit in small acoustic array for spatial localization［J］. Journal of Vibration and Acoustics, 2018, 140(4): 041013.
［18］RAO S S. Mechanical vibrations［M］. 5th ed. Upper Saddle River, NJ, USA: Prentice hall, 2011: 603-606.
