Research And Implementation Of Miniaturized Underwater Acoustic Navigation Terminal Processor

This article focuses on the real-time and high-precision acoustic navigation requirements of small-scale platforms such as underwater vehicles for underwater operations,a miniaturized acoustic navigation terminal processor with small size,light weight,and low power consumption is studied and implemented,which can receive underwater acoustic broadcast signals from long baseline positioning system buoys and perform real-time detection and processing.The platform position information is calculated using the principle of spherical intersection to achieve high-precision acoustic navigation function.Firstly,based on the working principle of the buoy type long baseline positioning system,the functional requirements and design indicators of the underwater acoustic navigation terminal processor were proposed,and targeted scheme design was carried out.Based on the main functions and design indicators of the processor,suitable boards were selected for the hardware platform in the processor,corresponding underwater acoustic broadcasting signals were designed,and the amplitude of the input signal of the navigation terminal processor at the maximum operating distance was calculated.Secondly,the software of the underwater acoustic navigation terminal processor was designed and implemented.The overall software scheme design,data acquisition module program design,signal processing algorithm design,and signal processing software implementation were carried out in sequence.In the design of signal processing algorithms,emphasis was placed on algorithm simulation analysis of signal detection algorithms,signal decoding algorithms,and position solving algorithms,and appropriate algorithms and corresponding parameters were selected.When implementing signal processing software,allocate software work reasonably based on the structural characteristics of the AM5729 processor.The ARM part will undertake the main logical operation work,data reception,and network communication functions,while the DSP part will undertake the main mathematical operation work and accept the control of the ARM part.Detailed design and implementation of the main and sub threads of the ARM side program,as well as the DSP side program were also carried out.Finally,the software and hardware of the navigation terminal processor were tested and verified.Basic functional tests were conducted on the power management,data acquisition,parameter setting,signal processing,positioning calculation,and network communication functions in the processor.The tests showed that each module worked normally and could achieve corresponding functions.After the basic functional testing is completed,the overall functionality,dynamic range,equivalent operating distance,overall power consumption,and weight indicators of the navigation terminal processor are tested in the laboratory,and the test results meet the design requirements.In order to further verify the performance of the navigation terminal processor in actual environments,the positioning solution results of the navigation terminal processor were compared with GPS measurement values in the outfield.The test results indicate that the two are in good agreement.The miniaturized underwater acoustic navigation terminal processor implemented in this article can achieve the expected functions and meet the design requirements.