Receiving And Acquisition System Design Of Multi-Channel Array

Underwater array signal processing has played an irreplaceable role in the field such as locating of underwater object and underwater communication and has been paid more attention. Underwater acoustic data acquisition system is the base of array signal processing and is indispensable in the field of underwater acoustic. This paper studies and designs a multiple array receiving and collecting system, including design of the hardware platform and realization of the software.Hardware platform design includes an analog receiver circuit, data acquisition and controlling circuit, USB interface circuit, and DA convert circuit. Analog receiver circuit aims to the array's original signal amplification, filtering noise, and adjustable gain. FPGA has numerous IO and plentiful storage recourses can easy meet the system's requirement. It is selected to be the main controller of the data acquisition and control circuit, and is also responsible for the circuit's logic and control; the data acquisition is completed by one ADS8548 Analog-to-Digital converter which makes the collection of the eight-channel voltage signal simultaneous. Acquisition system and host computer is connected by the USB,which makes the device use easy, plug and play. DA convert circuit is used to generate sine wave which can help the system to accomplish self-checking and adjust phase error between different channels.FPGA software, USB firmware and PC application program comprise the System software. 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 USB firmware program is the code running on the USB chip which is configured to work on the SLAVE FIFO mode with automatic data forwarding. Using NI-VISA create the USB driver has the characteristic of short time cycle and high efficiency. Host computer application program is based on LabVIEW which calls the VISA node control to read, convert, display and store the uploaded data.Finally, by laboratory tests, multi-channel array receiving and collecting system goes well,meets the design requirements.