Design of Low Power Underwater Acoustic Receiving Circuit with Digital Gain Control

Abstract

We propose a design of low power underwater acoustic receiving circuit by inverted echo sounder (IES) for observing the internal waves of the ocean in a long term. To receive the echo of the underwater targets, the underwater acoustic signal processor is required to be insensitive to strong noise and work in large dynamic range. In this work, with the variant application environments, to reduce the load of the subsequent processing modules, the circuit with digital gain control is employed to amplify the weak signals. Then, the out-of-band noise and higher harmonic are filtered out. The output is finally obtained by the 24-bit high-precision A/D sampling. Experiments demonstrate that the proposed design of the circuit performs with low power consumption, low noise, large dynamic range, flexible frequency selectivity, high precision and anti-inference.