Application Of Ultrasonic Phase Control Focusing Technology In Underwater Mapping

With the development of ocean detection technology in our country,the existing sonar system has gradually ceased to meet the requirements of high-precision detection.And these instruments,which were restricted to the domestic technology level,often need to be imported by the high cost.Therefore,it is urgent to develop a new type of underwater detecting instrument,to make up for the flaws of the current.In order to improve the accuracy and detection efficiency of underwater detection under the condition of reducing economic cost,an ultrasonic array underwater scanning imaging system,which is based on ultrasonic phased focusing technology,was introduced.In the early stage of the project,the research of the background of the ocean exploration and the current research status at home and abroad were carried out,and the research route of the project was planned.According to the research route of the project,the major research work was summarized as follows:1.Based on the acoustic field radiation principle of transducer,the basic principle of ultrasonic phase control technology and the working principle of acoustic lens were analyzed.The phase delay formula of acoustic beam deflection and the acoustic field radiation model of acoustic lens were given.2.The performance of ultrasonic array transducer was analyzed.Through numerical simulation,the feasibility of improving the focusing performance of array transducer by using phase control technology and acoustic lens focusing technology was verified.Secondly,the parameters of transducer were determined by numerical simulation,including geometric size and working frequency.Thirdly,the sound field characteristics of ultrasonic array transducer were measured,and the effectiveness of the technology of phase control and acoustic lens focusing technology to improve the focus performance of the array transducer from the perspective of experimental testing.At last,the echo test was carried out,and the receiving performance of transducer was analyzed from the angle of echo characteristic.3.The ultrasonic array underwater scanning imaging system was introduced.The composition,the corresponding relationship between system function and the module of the system was analyzed through the ultrasonic array transducer subsystem,the hypogyny machine system and the upper machine system.4.First of all,the echo signal was analyzed in time domain and frequency domain,so that,the working state of the system and the effectiveness of each module function were verified.Thus,the method of ultrasonic echo delay extraction was studied,and the space position calculation model of underwater object scanning point was proposed.On this basis,40 scanning point space locations on the plane and surface plate were reconstructed,the calculation results were analyzed and the factors causing the error were discussed and the solution was proposed.In conclusion,some shortcomings of the article were pointed out.