基于软核双口随机存储器的超声回波发生器

摘要

To deal with the inconvenience of modifying waveform amplitude quantization value in ROM of the signal generator implemented by ROM based on DDS,the scheme of digital echo signal generator based on FPGA soft core DPRAM and USB was put forward.The wave generator utilized FPGA soft DPRAM instead of ROM as waveform memory,with address generator module,waveform amplitude quantization value were written into DPRAM via USB.Experimental results showed that the waveform data could be modified conveniently,the error between the parameters of the digital echo simulator and the upper computer were small.The echo signal generator could match the underwater ultrasonic target detector test interface and be used directly.%针对利用只读存储器实现的基于直接数字频率合成技术的信号发生器,其波形存储器中波形幅度量化值不易修改的问题,提出了基于FPGA软核双口随机存储器和通用串行总线接口的数字式回波信号发生器设计方案.该发生器利用FPGA软核双口RAM代替只读存储器作为波形存储器,并增加地址发生模块,通过通用串行总线接口将波形幅度量化值写入双口RAM.实验结果表明:波形数据修改方便,产生的回波参数与上位机设定的参数间误差较小,所设计的回波发生器可与水下超声目标探测器测试接口匹配并直接使用.