A method of array shape calibration based on time delay estimation using two auxiliary sources

As for a flexible horizontal array deployed in the sea,it is difficult to obtain each sensor's precise relative position.Therefore a method of array shape calibration is proposed.The method is described as follows.Firstly two separate auxiliary sources are deployed.Secondly time delay of each sensor's received signal is estimated.Finally,with the aid of GPS location of the sources and the horizontal array,relative sensor positions of the horizontal array can be determined.The estimation of relative sensor positions is unbiased.Simultaneously,simulation analysis has been done to estimate its standard variance,and the optimal flare angle of the two sources has been derived.Data of 2001 Asian Sea International Experiment have been used to validate the method.After array calibration,measured source azimuth angle agrees with the real one,and measured array gain agrees with the theoretical gain.In conclusion,the theoretical and experimental results both show that the method can determine each sensor's relative position precisely.