Research On The Application Technology Of Navigation Based On Acoustic Doppler Current Profiler

The Acoustic Doppler velocity profiler(ADCP)is a kind of sonar equipment based on the Doppler Effect to measure vertical section current velocity,which is widely used in underwater navigation,deepwater oil and gas exploration,near-shore wave observation,river flow and harbor observation.It has significant meaning to the development of related subjects.Focusing on the use of ADCP in underwater vehicle navigation,dead reckoning and wave directional spectrum estimate technology are studied in this thesis.Dead reckoning is done according to the absolute velocity information of ADCP,common coordinates and their mutual transformation are introduced,the performance of dead reckoning is analyzed,the effect of measuring equipment error and the correction of array installation errors are especially studied.Contrastive analysis of traditional average velocity calibration method,recursive least-squares calibration method and nonlinear least square calibration method are made.Then the simulation,and experiment results are given.At last,the dead reckoning method is realized on the hardware platform of DSP,and a out-field experiment is taken to test and verify it.To the aspect of wave directional spectrum estimate technology,to improve the sailing safety and the calibration success rate of carrier floating calibration and sailing depth change,wave directional spectrum estimate is studied with the use of current speed profile information from ADCP,which can monitor the wave condition and provide controlling information for the navigation unit.The theory of wave directional spectrum measurement is analyzed.Then the estimate methods of height spectrum,cross spectrum and directional function are studied,which is needed by wave directional spectrum estimate.Then the principles of ADCP measuring wave direction spectrum is introduced,there are three wave direction estimation algorithm: Fourier Series Algorithm(DFTM),Iterative Maximum Likelihood Algorithm(IMLM)and Genetic Algorithm(GA).The performance of three wave algorithm is compared by numerical simulation and the experiment,which provides a reference for practical application.