摘要
为实现低信噪比条件下的水声瞬态信号检测,该文提出子波检测和局部瞬时能量密度级双重降噪方法。该双重降噪方法通过自适应选取含有用信号的某阶固有模态函数(IMF),计算Hilbert能量谱并进行局部积分,滤除子波检测残留下来的带外噪声。此外,结合宽度-包络联合检测机制,构造了水声瞬态信号局部瞬时能量密度检测器。湖试数据处理结果表明,局部瞬时能量密度检测器可有效降噪并在低信噪比条件下提取瞬态信号,较传统能量检测器具有更好的检测性能。
In order to detect acoustic transient signal at low SNR,a double noise reduction method of sub-wave detection and partial instantaneous energy density level is proposed.A certain order of Intrinsic Mode Function（IMF） containing useful signal is selected adaptively.Then Hilbert energy spectrum is calculated and integrated partially to filter out the residual out-off-band noise.In addition,an acoustic transient signal partial instantaneous energy density detector is established combined with width-envelope detection tactics.Lake trial data processing results show that the partial instantaneous energy density detector can reduce noise effectively and extract transient signal at low SNR.It has better performance than the traditional energy detector.
出处
《电子与信息学报》
EI
CSCD
北大核心
2013年第7期1720-1724,共5页
Journal of Electronics & Information Technology
基金
国家自然科学基金(51209059
51279043)
水声技术重点实验室基金(9140C200203110C2003)资助课题
关键词
信号检测
瞬态信号
Hilbert-黄变换
子波检测
局部瞬时能量密度级
能量检测器
Signal detection
Transient signal
Hilbert-Huang Transform（HHT）
Sub-wave detection
Partial instantaneous energy density level
Energy detector
