摘要
针对参量声源自解调信号失真问题,根据"Berktay远场解"对其进行了理论分析,并通过实验对理论分析结果进行了验证,发现:"Berktay远场解"对自解调信号中的基频、差频可以较准确地预测,而对导致信号失真的主要因素如二次谐波、和频等的预测误差很大,不能作为失真分析的精确依据;差频不是导致参量声源自解调信号失真的主要原因,降低失真的有效途径是减小自解调信号中二次谐波、和频分量,从而使有害频率成分的数量及幅值得到有效抑制。本项研究揭示了导致参量声源自解调信号失真的主要因素及其变化规律,可为参量声源信号处理方法的研究提供有益参考。
The distortion problem of the self-demodulated signal of parametric sound source is analyzed theoretically according to the ＂Berktay far-field solution＂, and the theoretical analysis result is verified with some related experi- ments. The results show that the ＂Berktay far-field solution＂ can predict the fundamental frequency and difference frequency at an acceptable precision;but for the main factors that cause signal distortion, such as second-order har- monic wave and sum-frequency wave, the prediction errors are too large to be accepted, which means that the ＂Berk- tay far-field solution＂ can not be used as the theoretical basis for analyzing the distortion. The difference frequency signal is not the main factor causing the distortion of the self-demodulated signal of parametric sound source ; and the effective approach to reduce the distortion is to reduce the second-order harmonic and sum-frequency components, which can suppress the quantity and amplitude of the harmful frequency components effectively. This study reveals the main factors contributing to the self-demodulated signal distortion and their varying rule, which can provide a helpful reference for investigating the signal processing methods of parametric sound source.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2013年第8期1771-1778,共8页
Chinese Journal of Scientific Instrument
基金
国家自然科学基金(60901062
61271286)资助项目
关键词
参量声源
自解调信号
失真分析
Berktay远场解
信号处理
pmmnetric sound source
self-demodulated signal
distortion analysis
Berktay far-field solution
signal processing
作者简介
杨天文，2005年于电子科技大学获得硕士学位，现为电子科技大学博士研究生，主要研究方向为参量声学阵、机械电子工程及测试技术。E—mail：ytwworld@163．com黄大贵，现为电子科技大学教授、博士生导师，主要研究方向为测试计量技术及仪器和机械电子工程。E—mail：de_huang@vip．163．com
