Signal demodulation method of portable multifunctional optical fiber hydrophone

Abstract

The invention relates to a signal demodulation method of a portable multifunctional optical fiber hydrophone, comprising the following steps: three-path analog input is accessed into an A / D conversion module after passing through a signal conditioning circuit, the A / D conversion module is connected with an FPGA, four-path D / A conversion module is connected with the FPGA, an output end of the D / A conversion module is connected with an output analog voltage signal of the signal conditioning circuit, an FPGA chip is connected with a DSP chip by an external bus interface, and the FPGA is used for controlling the DSP to reset, start and load program; a flash memory is internally stored with 3*3 coupler digital demodulation algorithm DSP program and PGC quadrature complex demodulation algorithm DSP program which are uploaded into the DSP by the FPGA according to the selection of the user, so that one-path 3*3 coupler digital demodulation or three-path PGC digital demodulation can be realized. The signal demodulation method has the advantages of low energy consumption and cost as well as being portable and multifunctional, so as to provides a reliable, fast and convenient tool for the study of the optical fiber hydrophone and array thereof.

Description

technical field [0001] The invention relates to the field of optical fiber hydrophone signal phase demodulation, and mainly relates to a portable multifunctional optical fiber hydrophone signal demodulation method. Background technique [0002] Interferometric fiber optic hydrophones are a new type of hydrophone developed in the late 1970s. Compared with piezoelectric ceramic hydrophones, fiber optic hydrophones have the advantages of easy adjustment of sensitivity, easy array multiplexing, and array resistance. Due to the advantages of strong electromagnetic interference capability and fewer components to form large-scale arrays, fiber optic hydrophones and array technologies have developed rapidly in recent years. [0003] Signal demodulation is a key technology in the development and application of fiber optic hydrophones and arrays. Since the acoustic signal is modulated in the output signal of the interferometric hydrophone in the form of phase modulation, the output s...

AI Technical Summary

Problems solved by technology

At present, when conducting research on fiber optic hydrophones and fiber optic hydrophone arrays, general-purpose signal acquisition cards, signal sources, and PCs are usually used to build test platforms, which occupy a large space and are inconvenient to move, and the introduction of other uncertain factors may increase the platform construction. , which brings difficulties to the research

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