摘要
对于存在不同线谱成分的宽带信号而言,提取这些线谱成分进行恒定束宽波束形成,可以达到增强信号的目的。自适应陷波器(Notch滤波器)具有频率跟踪和相位估计的特性,基于此提出了一种自适应恒定束宽波束形成技术。对于基阵接收到的信号,以其各阵元之间的相位差为媒介,在Notch滤波器离线重构相移波束形成中提取"低频慢变化"的相位信息,对其进行补偿,使输出的重构信号具有"高频快变化"的相位信息,以此将不同频段的信号进行恒定束宽波束形成。以舰船辐射噪声为例,通过仿真和实验研究证实了该方法的有效性。
For the line spectrum of different frequencies existing in a wideband signaJ, the constant beamwidth beam- forming can strengthen the signal. Based on the characters of an adaptive Notch filter in tracking frequency and esti- mating phase, a new technique of constant beamwidth beamforming is proposed. For the signal received by an array, the Notch filter forms a set of input signals through phase delays between different unit sensors. In beamforming, the adap- tive Notch filter changes the ＂slow-varying phase information in low frequencies＂ into the ＂fast-varying phase informa- tion in high frequencies＂ for the output reconstructed signals by compensating phase delays. This process can be done in different frequency bands in order to realize the constant beamwidth beamforming. In this paper, the ship noise is taken as an example to simulate and test the effectiveness of the method.
出处
《声学技术》
CSCD
2013年第1期50-53,共4页
Technical Acoustics
关键词
自适应陷波器
恒定束宽
波束形成
adaptive notch filter
constant beamwidth
beamforming
