摘要了解了直接数字频率合成器(DDS)信号发生器的原理和AD9852信号发生器的性能优点,分析了几种不同低通滤波器的设计,重点描述并设计了椭圆低通滤波器,椭圆滤波器不仅要滤除高频信号,还要去除DDS的谐波杂散和边带杂散信号,因此低通滤波器是信号发生器中信号处理的重要部件。结合滤波器的指标,综合运用归一化法完成了椭圆低通滤波器的设计,使它的通带截止频率为120MHz、通带内最大衰减为0.2dB、在135MHz处的衰减为66dB。最后再用multisim 10.0进行仿真,观察输入输出波形以及幅频特性曲线,验证是否满足设计要求。64576
毕业论文关键词 DDS 椭圆滤波器 归一化法 multisim
毕业设计说明书(论文)外文摘要
Title Low-pass Filter Design And Simulation Based On DDS
Abstract Mainly understands the principles of the Direct Digital Frequency Synthesizer (DDS) signal generator and the performance benefits of the signal generator of AD9852,analyses several low-pass filter design,and focuses on the design of the elliptic low-pass filter,the elliptic filter is not only to filter out high frequency signals,but also to remove the spurious harmonic and spurious sideband signal of the DDS,so the low-pass filter is the most important component in the signal generator. Combined with the filter indicator,I use the normalized method to complete the elliptic low-pass filter design,the filter has a passband cutoff frequency of 120MHz, the maximum passband attenuation of 0.2dB, the attenuation of 66dB at 135MHz . Finally ,use multisim 10.0 to simulate,observe the input and output waveform and the amplitude-frequency characteristic curve and verify if it meets the requirements.
Keywords DDS elliptic filter normalized method multisim
1 引言 1
2 直接数字频率合成器DDS 3
2.1 DDS的组成 3
2.2 DDS的应用 4
3 DDS信号发生器AD9852 6
3.1 AD9852介绍 6
3.2 AD9852的性能指标 7
4 低通滤波器的设计 8
4.1 巴特沃斯低通滤波器设计 8
4.2 契比雪夫低通滤波器设计 9
4.3 椭圆低通滤波器设计 10
5 椭圆函数滤波器的设计 12
5.1 归一化和去归一化方法介绍 12
5.2 用归一化法设计椭圆低通滤波器 12
5.3 去归一化 14
5.4 计算后的元件值构建电路图 14
6 用multisim 10.0进行电路图仿真 16
6.1 仿真软件mutisim 10.0介绍 16
6.2 仿真电路的设计与连接 16
6.3 输入输出波形的对比仿真 17
6.4 仿真的幅频特性曲线 22
6.5 仿真结果以及得出的结论 24
7 工作总结与展望 26
结 论 27
致 谢 28 基于DDS的低通滤波器设计与multisim仿真:http://www.youerw.com/tongxin/lunwen_71844.html