Single Vector-Sensor Doppler Positioning Research

Acoustic positioning technique has become the focus of research in the field ofunderwater acoustic. This paper mainly studies the acoustic positioning method based on asingle vector sensor using frequency-azimuth target motion analysis. This method not onlycan be used in the field of underwater acoustic positioning, but also provides a basisfor exploring the new technology of sonar signal processing.The line spectrum of ship-radiated noise contains a wealth of information of the target,extracting the line-spectrum of ship-radiated noise has the vital significance of the targetdetection and passive location.This paper extracts the line-spectrum signal of ship-radiatednoise based on a single vector sensor and to realize the ship passive location.The method ofextracting the line spectrum is to extract the envelope of ship-radiated noise,this paperdescribes three envelope extraction methods and compares their strengths and weaknesses,choosing which type of method generally is to see the actual situation.Because the envelopeextracted exists interference, so this paper also introduces a kind of purification methods-1.5dimensional spectroscopy.Effectively estimating the orientation and movement speed of the target is the key ofpassive location.A single vector sensor can estimate a full range of the target orientationwithout fuzzy and it is not affected by frequency effect. When ship is in the course of thevoyage, signal at the receiving point will produce a Doppler shift which contains speedinformation. Therefore, to achieve the target passive location must first gain signal azimuthand frequency sequence.This will need to select a kind of effective orientation estimation andfrequencyestimation techniques.Because ship radiated noise is broadband spectrum signal envelope modulated by theline spectrum, so choose acoustic intensity averager method which has good performance ofDOA estimation of single target radiated continuous spectrum noise to DOA estimation. Forfrequency estimation technology,this paper choose small burden and high estimation precisionfrequency auto-tracking adaptive frequency estimator to estimate frequency.The simulation experiment shows, in the certain model conditions, the proposed passivelocation method is feasible, and therefore this method is of some significance for the shippassive locating research.