一种改进型FX结构在线建模有源噪声抵消系统

ONLINE MODELING OF AN ANC SYSTEM WITH SECONDARY PATH AND MODIFIED FX STRUCTURE

次级通道等声信道的存在是ANC系统区别于自适应信号处理的最主要特征。它们的存在使得系统不再是一个单纯的电学问题,更多的涉及到声场的研究。次级通道使得控制滤波器产生的次级噪声不能立即和主输入噪声进行相消干涉,这降低了系统的性能。正是由于这一通道的存在,建模速度和建模准确性将直接影响系统的性能。文中针对水下潜艇被动声纳平台接收端有源降噪技术,提出一种新型的FX结构在线建模ANC系统,该系统增加了控制滤波器误差输出预测滤波模块,降低了控制滤波器误差输出对建模的不利影响,大大提高了建模精度和系统收敛性能。通过计算机仿真,以及对真实海试数据的处理结果可以直观的看到,该种方法使得系统的总体性能得到显著提高。

Existence of secondary channel and other acoustic channel is the main feature of an ANC system being different from adaptive signal processing systems.Their presence allows the system is no longer a simple electrical problem,more involving in acoustic field study.Secondary channel renders that the secondary noise generated by the control filter can't be canceled with main input noise immediately and weakens the system performance.Due to this channel,the modeling speed and accuracy will directly affect the system performance.A new stype of an online FX modeling ANC system is proposed for the ANC technology of an receiver of underwater passive sonar platform.It increases a model of an output prediction error filter to the control filter,reduces the effects of the output error of the control filter on the modeling significantly,improves the accuracy of the modeling and the system convergence performance,raises the overall system performance significantly.