声学参量阵再现差频波声场响应特性与控制

Control schemes and characteristics of reproducing difference frequency acoustic response in acoustic parametric arrays

基于再现差频波声场响应非线性的特点,系统研究了调幅方式、声信号预处理等方面对再现差频波声场响应和功率消耗的影响,分析得到了波形、带宽、调幅系数、频率对失真度之间的关系.提出对单频声信号采用单边带调幅,对多频声信号采用拟合包络形状的方法.通过对3种控制处理方式在发射实时采集信号情况下的能耗和频谱方面的计算和对比,论证了单边带调幅和拟合方法,优化和改善了声学参量阵再现差频波声场的带宽要求和损耗.

Based on the nonlinear characteristic of sound filed response of reproducing difference frequency wave, study on the influence of amplitude modulation and the preprocessing of sound signal on acoustic distortion and power consumption. The relationship between waveform and bandwidth and modulation factor and frequency and degree of distortion is analyzed. The single side band modulation for signal tone and a curve fitting signal processing method for composite tone are presented. Three kinds of control schemes have been calculated and compared with frequency spectrum and power consumption. Result shows the single sideband amplitude modulation and curve fitting method can optimize the bandwidth and energy consumption of reproducing difference frequency wave sound field.