Design And Implementation Of Multi-channel Acoustic Signal Acquisition System

With the development of marine and underwater acoustic technology,underwater signal processing becomes the necessary technical means in the area of sea exploration,navigation,underwater communication and so on.However,underwater acoustic data acquisition is an integral part of underwater signal processing,it is the primary prerequisite for signal processing.A superior performance,as well as real-time multi-channel data acquisition system in underwater acoustic systems are playing an increasingly important role.The application meaning attributes to the Underwater array signal processing.This paper studies and designs a multi-channel data acquisition system,including design of the hardware platform and realization of the software.Design of the hardware platform includes Analog-to-Digital acquisition circuit,USB communication control circuits,FPGA core control circuit and so on.FPGA is selected to be the main controller of the data acquisition and control circuit,and is also responsible for t the Analog-to-Digital sampling timing control module and USB communication control logic as well as cache data acquisition and digital filtering.And the data acquisition is completed by one ADS8548 Analog-to-Digital converter which makes the collection of the four-channel voltage signalsimultaneous.Acquisition system and host computer is connected by the USB,which makes the device use easy,plug and play.System software mainly consists ofthe FPGA software,USB firmwareand PC application program.The FPGA software is accomplished by Verilog HDL language mainly including data acquisition control and the logic control of the FPGA and USB interface communication.The FPGA software using Verilog HDL language programming language,include A/D logic control,USB slave FIFO logic programming,internal data cache FIFO design,and programming of digital filter.The USB firmware program is configured to work on the SLAVE FIFO mode with asynchronous automatic transmission for 16-bit data.Using NI-VISA create the USB driver has the characteristic of short time cycle and high efficiency.The PC application programis based on LabVEIW software which can read the USB uploading data in real time,and display and store data.Finally,through tests in the laboratory and pool,multi-channel data acquisition system goes well,meets the design requirements and achieves the desired effect.