摘要
通过推导宽带解调处理的输出信噪比公式,系统地分析了影响幅度调制的宽带信号检测的各种因素。分析表明,宽带调制信号检测性能取决于以下因素:信号的周期调制的深度、前置处理器带通滤波器的带宽、调制噪声在总的噪声中的比重、采样速率,以及计算解调谱时的傅里叶变换的长度、降样倍数、时间窗、数据块重叠程度以及平均次数。
The factors that influence the performance of the amplitude modulated broad-band signal detection are analyzed by deriving a formula for the output signal to noise ratio of DEMON(Detection of Envelope Modulation on Noise) processing. The analysis shows that the performance of the amplitude modulated broad-band signal detection depends on the following factors: depth of the periodical modulation of the signal, the bandwidth of a preprocessor, the ratio of modulated noise to total noise, the sampling frequency, and the length of DFT, the decimation number, the selection of time window, the overlap of data blocks and the number of averaging in calculating the demon spectra.
出处
《声学学报》
EI
CSCD
北大核心
2005年第4期373-378,共6页
Acta Acustica
关键词
宽带幅度调制
水声检测
信噪比
滤波器
傅里叶变换
声呐
Acoustic signal processing
Amplitude modulation
Discrete Fourier transforms
Noise abatement
Signal to noise ratio
