The Signal Generator Of Random Waveform With Extended Channels

With the development and utilization of the ocean, as well as the increasing demand of the marine resources, the underwater acoustic field is developed rapidly. Sonar, as the prior equipment in ocean exploration, plays an indispensable part in seafaring field of navy and civilian application. In active sonar system, underwater acoustic transducer needs specific incentive signal for researching, testing and repairing. Then the specific information can be received through the detection of that signal echo. Generally in underwater acoustics field, the sonar detection devices, such as for research, development, testing and troubleshooting,sensor array create signal with specific parameters, sometimes as building anti-echoic pool and even sea test platform. Therefore, if underwater acoustic signal generator can simulate the underwater acoustic sensor array signal in real time, the problem of sonar equipment researching, adjusting and repairing would be effective. It would also be economic, time saving, flexible and accurate.In the paper, a signal generator which can extend the channel is designed, which can simulates the signal of underwater acoustic sensor array. The paper mainly includes the construction of system hardware platform, the development of system software and the testing of the whole system performance. According to different functions, the hardware of the system can be divided to several modules including digital signal processing module, USB communication port module, multi-channel AD module and multi-channel analog signal conditioning module. Software of the proposed system mainly consists of host computer control, DSP, FPGA and USB unit software. Client has the access of taking control of the hardware via host computer under Windows System. The hardware is connected with host computer by USB. Then it can generate wave and transport data through USB port communication. Digital control module is mainly dealing with DSP and FPGA for data processing and logic control. DSP controls the USB port communication, which receives data from the host computer, for data analysis and command extraction. After FPGA receives the control commands and waveform data, the data will be stored in the RAM chips, or directly to the DAC unit for digital analog conversion. Finally, the signal will be outputted after analog signal filtering, attenuation and other processing by the analog signal conditioning module.At the end of the paper, the various units of the system and the whole machine are tested.The function, the index and the performance of the system are verified. The test results show that the system has good reliability and stability.