扬声器线阵列高频波导有效辐射率的测量方法

研究了一种获取扬声器线阵列高频波导有效辐射率的简单可靠的方法。利用乘积理论和菲涅尔原理,得出在副瓣角度处扬声器线阵列与单节高频波导的垂直指向性相等,且均与其有效辐射率呈sinc函数的简单关系。按照此理论,通过实验测量单节高频波导单元的指向性,得到线阵列的有效辐射率平均值为82.5%,并测量整个线阵列进行验证实验,计算均方误差为0.051。结果表明,该方法可以快速得到阵列的有效辐射率,且准确度高。 

A measurement method of active radiating factor of high-frequency waveguides of loudspeaker line arrays

A brief and accurate measurement method of active radiating factor of high-frequency waveguides of loud- speaker line arrays is studied. Based on the principle of multiplication and Fresnel principle, the theory illuminates the directivity response of line array is equal to that of the array element, which has a sinc function relationship with the active radiating factor. Experiments are designed based on the theory, and the results show that the active radiating factor is 82.5% and the mean square error of verification experiments between the calculated value and measured value is just 0.051. In conclusion, this method can obtain the active radiating factor as well as the directivity of the whole line array rapidly by single-pointed measurement of the directivity of array element.