Design And Realization Of Electronic Platform Of Acoustic Subsystem In Passive Positioning Buoy System

Passive Positioning Buoy System makes use of shipping noise to detect and track targets, which includes two parts of buoys subsystem and displaying and controlling subsystem. The former subsystem is also a vector hydrophone array made up of several buoys which detects the azimuth of underwater target through shipping noise. It sends the measure data to the controlling and displaying subsystem through the wireless channel. Meanwhile, the latter subsystem detects the GPS information of the buoys and uses the data and information above to calculate the position of target through principle of geometrical confluence.The acoustic system paper discussed is a part of buoys subsystem which is made up of Auxiliary electron cabin,Signal conditioning unit and Signal processing unit.The acoustic platform is able to handle signals from four channels:two channels of particle velocity signals, one vector pressure signal and one scalar pressure signal. Auxiliary electron cabin sends the four signals to the Signal conditioning unit through cables as well as the signal collecting unit gathering the information of position of hydrophone,depth and battery.Signal conditioning unit amplifies and filters the signal to improve the SNR and get the preparation of signal processing following. Signal processing unit consists of DSP which uses cross-spectral estimation to calculate target position with information of three channels of signals and FPGA instrument which is the key part of Signal processing unit to realize the storage, calling back and real time transition functions. Also, the FPGA provides the timing order for the system.The paper firstly summarizes the design of hardware electronic platform of Auxiliary electron cabin and introduces the designing method of singlechip. Secondly, the paper gives out the electronic circuit structure and the realization of each part. Thirdly, the paper introduces the method of program designing of FPGA and realization of each unit specificly. Lastly, an illustration of target azimuth estimation algorithm is given out which includes the realization method and working process.The simulation and results of experiment prove that the algorithm above is robust and effective.