Design And Implementation Of The Receiving Unit For The Scalable Positioning Acoustic System On Underwater Small Platforms

The combat capability of underwater unmanned platforms mainly depends on the performance of their payloads.Due to the size limitations of unmanned platforms,the size of the passive positioning sonar array that can be carried is limited,and the characteristics of miniaturization and lightweight are necessary.At the same time,considering the trend towards series development,load generalization,and software standardization of underwater unmanned platforms,the design of an acoustics system receiver with excellent performance,small size,and easy expansion is crucial for passive positioning payloads in unmanned applications.Based on the horizontal project "Small Underwater Platform Load Expandable Positioning Acoustic System",this paper focuses on the demand for small passive positioning sonar arrays in domestic underwater unmanned platforms and carries out the design and implementation of the positioning acoustic system receiver.The research content mainly includes the following aspects.(1)Hardware design of the receiver unit,mainly including the vector hydrophone low-noise signal conditioning circuit,multi-channel AD acquisition circuit,gigabit Ethernet transmission circuit,synchronous clock/pulse transceiver circuit,universal interface circuit,real-time clock circuit,and FPGA master control circuit design and implementation.(2)Software design of the multi-channel receiving electronic unit,implementation of software functions such as multi-node cascade automatic coding,multi-node cascade synchronous acquisition,multi-node cascade network relay transmission,gain daisy chain control,and depth heading data acquisition.(3)Software design of the synchronous control and data fusion module,implementation of software functions such as multi-array multi-node synchronous control,multi-array multi-node network data fusion,network relay transmission,system reset control,and real-time clock acquisition.(4)Functional performance testing of the receiver unit laboratory,mainly verifying the noise characteristics,filtering characteristics,multi-node serial cascade function,multi-node distributed cascade function,multi-node phase and amplitude consistency,gain control function,and gigabit network data transmission performance of the receiver unit.