基于双麦克风的2维平面定位算法

基于麦克风阵列的声源定位技术受到了越来越多的关注。在视频会议、助听器、免提电话系统中,声源定位被用于检测说话人的位置信息来自动调节摄像头,或者形成波束。在各种声源定位方法中,基于到达时间差(time delay of arrival,TDOA)估计的双步定位算法是普遍采用的一种行之有效的方法。Birchfield从能量的角度出发提出了一种基于双耳电平差(interaural level difference,ILD)的双步定位算法,它通过检测多个麦克风对所接收到的信号能量比来确定声源的位置。然而,所有的这些方法如果要确定出声源在二维平面内的位置坐标,都至少需要三个麦克风。针对这一问题,本文提出了一种基于双麦克风的二维平面定位算法,类似于人的双耳定位原理,我们通过同时估计声源到达两个麦克风的能量比和时延信息,来达到定位的目的,而进一步推导出的闭合解可以用于实时地跟踪运动声源。最后的仿真结果证明了这一算法在一般的混响条件下都可以获得好的结果,然而它减小了阵列的尺寸,这对于体积受限的通信设备来说具有极大的吸引力。

Dual-Microphone Source Location Method in 2-D Space

Array based source location attracts a growing interest nowadays,which is frequently used in videoconference,hearing aids and hands free telephone systems to detect a speaker's position.Time difference of arrival(TDOA)based dual-step source location is a popular method in this field.Recently,Birthfield proposes a new technique which is based on interaural level difference(ILD).It determines the source position by energy ratio from microphone pairs.However,all these localization techniques need at least three sen- sots to obtain a 2D source position.In this work,we combine the former two techniques,i.e.,ILD and TDE based techniques,to present a novel localization approach by an array of only two microphones,just like the source detection of human ear.The further derived closed- form solution can be applied to track the moving object.Our final simulation confirms that such method,which is thought to be more suit- able for the equipments with small size,can achieve a good result under normal conditions.