A Synchronous Ranging Device Based On NI CRIO

Underwater acoustic submersible buoy is widely used in ocean exploration,military deployment,resource development,etc.It has the advantages of good concealment,convenient deployment and recovery,and plays an important role in the current application of underwater acoustic navigation,tracking and positioning.Underwater acoustic ranging technology is the foundation and key of positioning.NI CompactRIO is a high-performance industrial embedded real-time measurement and control system manufactured by the National Instrument Company of the United States.A solid hardware structure makes it very suitable for harsh marine environment and small submarine electronic warehouse.This article designed an embedded synchronous ranging device based on NI controller and DSP TMS320VC5509 A aiming at the ranging function of submarine buoy positioning system.First,the system design index is analyzed and the design scheme is formulated according to the index.In the aspect of algorithm,different time delay estimation algorithms are designed according to the signal characteristics of broadband signal and narrowband signal respectively.The principle of the algorithm is elaborated in detail,and the influence of key factors in each algorithm on the result of time delay estimation is simulated and analyzed.According to the characteristics of underwater acoustic channel,a peak decision detection process is designed to reduce the false alarm probability and optimize the detection performance of the system through a variety of decision thresholds.In the aspect of Engineering implementation,high performance and low power chip TMS320VC5509 A is chosen as the hardware platform of the system,and high precision rubidium atomic clock is chosen as the time standard of synchronous ranging.According to the system requirements,the design of hardware chassis is completed by modules.On the basis of the algorithm transplantation,the corresponding DSP peripherals in the function realization are developed,including using McBSP to collect AD data,using DMA configuration of table tennis buffer,using timer to record delay and upload GPIO data.Finally,the design and configuration of custom C module are carried out according to NI company's development standard.NI CompactRIO 9030 is used as the host computer controller to design the interface communication mode and complete the interaction with distance C module.In the data storage stage of the host computer,the outlier point decision design is added to further smooth the ranging trajectory.Finally,the monitoring display and control interface and data storage program are designed based on LabVIEW software,and the design of synchronous ranging device system based on NI controller is completed.Through the power consumption,network connection and other functional tests conducted in the laboratory,it is verified that all the functions of the system are normal and the system runs stably,and the accuracy of the design meets the requirements of the target through the sea test data.