Design And Implementation Of Underwater Inductively Coupled Data Transmission System

When exploring ocean activities scientifically and collecting their hydrological elements,the information exchange between underwater data acquisition system and surface observation platform must be ensured through efficient and reliable data transmission system.Compared with the traditional underwater data transmission method,the underwater data transmission system based on inductive coupling can realize long-distance data transmission,the system transmission efficiency is high,and the nodes are not limited by position,which is convenient for networking and easy to realize multi-point communication.This paper mainly studies the design and implementation of underwater inductively coupled data transmission system.The transmission medium of the system is ordinary steel cable,which does not need built-in special transmission wires.It has the advantages of not easy to bend and low cost.The project has broad application prospects,including marine hydrological elements acquisition,data transmission between surface ships and UUVs,and between UUVs.It has the characteristics of high efficiency and reliability.Secondly,according to the test results,this paper proposes a phase trajectory optimization scheme of CPM signal using Hermite series,which makes the transmitted signal energy more centralized,reduces the out-of-band interference,improves the utilization of frequency band,and simulates and verifies the modulation and demodulation of CPM signal and implements it on FPGA.Finally,the paper completes the design and implementation of the hardware circuit and software program of the system,and uses the relevant software to simulate and verify each circuit module and program module respectively.For the power amplifier module,a new type of GaN half-bridge power stage class D power amplifier is used as the solution,which reduces the design complexity and improves the efficiency.In this paper,the relevant instruments and equipment are used to test each module of the system.According to the test results,circuit optimization and program design are carried out.The whole system is built and debugged.The validity and reliability of the system are verified,which lays a foundation for further practical application.