The design of high-speed real time multi-channel sonar simulation signal source based on FPGA parallel technology

The mainly task of sonar simulation signal source is to generate real time dynamic echo signal using the underwater acoustic signal properties, the relative motion properties and the underwater environment noise. Sonar simulation signal source is applied in a semi-physical simulation system. So real time ability and high-speed transmission is the main factors in the system design. This paper using the embedded soft real time processor combining high speed hard real time module to generate 128 channel simulation signals based on FPGA parallel technology. Single frequency pulse signal (CW), line frequency modulation pulse signal (LFM), hyperbolic frequency modulation pulse signal (HFM), this three type of pulses signals have dynamic generated through above technology in the system. The system test results show that the average compute time of FPGA module is consumed 9.13867 ms when working at 192 KHz, the highest system sampling rate to generate 128 channel signals. Meanwhile, less than 2.5 K system flash memory space is needed to ensure continuous simulation signal output. Experimental results show that System has high real time ability and reliability.