Research On The Analysis And Compensation Of The Effect Of Phased Grating Lobe On Velocity Deviation

Regardless of whether it is civilian or military,the most important thing for a ship to sail at sea is to grasp its real-time geographic location.Phased Doppler velocity sonar is an important device for accurate underwater navigation.However,due to factors such as carrier attitude change,terrain fluctuations,beam spreading and other factors,grating lobe beam confusion causes velocity deviation,at the same time,it will also cause the asymmetry of the Doppler power spectrum and cause errors by the traditional frequency measurement algorithms.In order to further improve the speed measurement performance,this paper studies the effect of the grating lobe beam on the speed measurement deviation and the optimization of the frequency measurement algorithm.First consider the speed deviation caused by the phased grating lobe beam.Based on the echo signal generation mechanism,different environmental conditions such as ship speed,sailing attitude of the base platform,signal pulse width,energy suppression ratio,topographic fluctuations and bottom depth are compared.Speed measurement deviation under the analysis of these factors to limit the size of the speed measurement deviation;Secondly,the bottom echo and stream echo signal models are constructed,the spectrum analysis is performed and the pulse pair algorithm is used to estimate the frequency of the built echo signal model.Analyze the speed measurement deviation in different situations to verify the effect of the grating lobe beam on the speed measurement performance.Finally,based on the gradual progress of the autocorrelation function,an improved interception algorithm and an overdetermined algorithm with significant optimization effects on the asymmetric spectrum are obtained.The application of the phased array grating lobe to the compensation experiment of the velocity deviation has laid a theoretical foundation.