中文摘要：

提出了一种以FPGA为主控芯片、基于DDS技术的多信号合成设计方案,并用硬件实现了该系统。系统主要实现两个功能：首先,实现了输出8路频率、相位和幅度可调的正弦波信号;其次,将8路正弦波信号叠加后输出,完成了多路信号合成的硬件实现。硬件系统由数字逻辑部分和模拟电路两部分组成;数字逻辑部分在QuartusⅡ8.1上设计,并通过Active Serial Programming下载到FPGA的配置芯片EPCS4中,逻辑功能都在FPGA芯片内部完成;该部分控制液晶显示器和键盘,实现对正弦波信号的调制输出;模拟电路部分在Altium Designer Summer 09上设计,应用PCB工艺制作成电路板。模拟电路部分连接数字逻辑部分的输出,完成调制信号的滤波和信号合成。

英文摘要：

A multi- signal synthesis design scheme based on DDS technology is proposed,in which FPGA is taken as the main control chip. The system has been already realized with hardware. The system can output 8-channel sinusoidal wave signals with adjustable frequency,phase and amplitude,and realize the hardware of multi-channel signal synthesis by output of the superimposed 8-channel sinusoidal wave signals. The hardware system is composed of digital logic unit and analog circuit. The digital logic unit is designed on Quartus Ⅱ 8.1,and downloaded to the configuration chip EPCS4 of FPGA by Active Serial Programming. All the logic functions are realized inside the FPGA chip,which can control the liquid crystal display（LCD） and keyboard,and realize the modulation output of the sinusoidal wave signal. The analog circuit is designed on Altium Designer Summer 09,and the circuit board is produced with PCB technique. The analog circuit is connected to the output of digital logic unit to implement the filtering and synthesis of the modulating signals.