聚偏氟乙烯压电薄膜换能器前置放大模块设计

Design of Preamplifier Module for Piezoelectric Thin Film Transducer in Polyvinylidence Fluoride

基于前置放大模块的噪声特性直接影响聚偏氟乙烯(PVDF)压电薄膜换能器的接收性能,根据PVDF压电薄膜换能器的特点,采用模拟信号处理中抑制噪声的关键技术,实现与之配套的前置放大模块的设计,总结了前置放大模块的设计要素,利用Multisim 12对设计电路进行仿真,并对该模块进行了实验室测试。试验结果表明,该模块输入噪声不大于–130 dB/Hz^(1/2),可满足水声信号处理设备的使用需求。

The noise properties of a preamplifier module directly influence the receptivity of a piezoelectric thin film transducer of polyvinylidence fluoride（PVDF）. According to the characteristics of the PVDF piezoelectric film trans- ducer, this paper designs a preamplifier module to match the transducer. Interferences and noises are eliminated by the anti-interfere technology applied for analog signal processing. The design factors of the preamplifier module are considered. The design module is simulated via the software Multisiml2 and tested in laboratory. The results show that the input noise of this module is lower than -130dB/√Hz which infers that the designed preamplifier module meets the requirement of underwater acoustic signal processing equipment.