一种低功耗微弱信号放大电路的优化设计与研究

针对远距离声源发射的水声信号微弱、水声接收设备电源能量有限的特点,提出一种功耗小、对无源元件误差灵敏度低、高增益放大的微弱水声信号通用放大电路。系统采用场效应管共源单调谐放大器为前置放大级,由四级级联低功耗运放构成带通滤波放大电路,省去传统的R、C低通网络,实现了对微弱水声信号的高增益放大和海洋背景噪声的归一化处理。通过计算电路网络传递函数极点证明了电路系统的稳定性。海上使用表明系统具有精度高、适应性强、电路稳定性好、功耗小等优点。

For the problems of the small signal which travels from the distance and the limited power of acoustic receiver underwater,a kind of design for acoustic general amplifier is presented with low power consumption,high gain amplification and low sensitivity to the errors of passive elements.The electro-circuit system is made up of preamplifier and band-pass filter which comprises four operational amplifiers in series instead of RC low-pass net.This design is applied to possess capabilities that the high gain amplification of small signal and pre-whitening process of sea noise background.The computation of poles of the transfer function shows that the designed amplifier is stable.Sea test proves that the system has merits of high precision,good adaptability,stable performance and low power consumption.