基于FPGA的一种数字下变频设计
发布时间：2018-07-15 18:26
【摘要】：随着科学的进步,社会的发展,软件无线电这一概念也随着科技的进步而诞生。在软件无线电中,其主要的通信功能是由软件提供和实现的,硬件只是提供一个基本平台,硬件设备不会随着通信系统的发展而淘汰不需要要逐步更新,并不像传统通信设备,让软件仅仅作为无线通信的基本平台,让硬件起主导作用。但是,由于目前硬件水平的限制,DSP处理器不能直接处理从A/D采样而来数据,所以数字下变频是目前软件无线电不可缺少的一部分。在21世纪的今天,可编程逻辑器件已经发展到一个相当成熟的地步,这其中FPGA(现场可编程门阵列)属于发展的相当最完善的。所以现在电子电路的设计基本是基于FPGA的。采用FPGA设计数字下变频也十分便利。本文首先对数字下变频的基础理论:采样理论和多速率数字信号处理理论进行介绍和研究,对NCO的生成算法进行比较和其性能的优劣,着重介绍了CORDIC算法的特点和其优势。然后对基于FPGA的数字下变频的各模块:NCO(数字控制振荡器)、CIC(积分梳状滤波器)、HBF(半带滤波器)、FIR低通滤波器分别进行研究其理论、结构、及实现方法,在设计过程中通过调用Modelsim对各个模块进行仿真调试,用Matlab做频谱分析以使其达到设计要求。最后通过本设计所用的Altera的EP4CE15F17C8的芯片和AD公司推出的AD9280芯片再配合Matlab的FDAtool工具设计生成一个输入信号在0.1-0.4MHz采样频率为32MHz的数字下变频器,通过频谱仪和信号发生器对其做板级测试。
[Abstract]:With the development of science and society, the concept of software radio was born with the progress of science and technology. In software radio, its main communication function is provided and realized by software. Hardware only provides a basic platform, and hardware equipment will not be phased out with the development of communication system. It is not like traditional communication equipment. Let the software only as the basic platform of wireless communication, let the hardware play a leading role. However, due to the limitation of current hardware level, DSP processor can not directly process data sampled from A / D, so digital downconversion is an indispensable part of software radio at present. In the 21st century, programmable logic devices have been developed to a rather mature stage, in which FPGA (Field Programmable Gate Array) belongs to the most perfect development. So now the design of electronic circuit is based on FPGA. Using FPGA to design digital downconversion is also very convenient. This paper first introduces and studies the basic theory of digital down-conversion: sampling theory and multi-rate digital signal processing theory, compares the generation algorithm of NCO and its performance, and emphatically introduces the characteristics and advantages of Cordic algorithm. Then, the theory, structure and implementation method of every module of digital down-conversion based on FPGA are studied, such as: NCO (Digital controlled oscillator) CIC (integral comb filter) / HBF (half Band filter) / Fir low pass filter. In the design process, each module is simulated and debugged by calling Modelsim, and the spectrum analysis is done by Matlab to make it meet the design requirements. Finally, the EP4CE15F17C8 chip of Altera and AD9280 chip developed by AD Company are used in this design to generate a digital downconverter with input signal sampling frequency of 32MHz at 0.1-0.4MHz. It is tested at board level by spectrometer and signal generator.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN791
本文编号：2124991
[Abstract]:With the development of science and society, the concept of software radio was born with the progress of science and technology. In software radio, its main communication function is provided and realized by software. Hardware only provides a basic platform, and hardware equipment will not be phased out with the development of communication system. It is not like traditional communication equipment. Let the software only as the basic platform of wireless communication, let the hardware play a leading role. However, due to the limitation of current hardware level, DSP processor can not directly process data sampled from A / D, so digital downconversion is an indispensable part of software radio at present. In the 21st century, programmable logic devices have been developed to a rather mature stage, in which FPGA (Field Programmable Gate Array) belongs to the most perfect development. So now the design of electronic circuit is based on FPGA. Using FPGA to design digital downconversion is also very convenient. This paper first introduces and studies the basic theory of digital down-conversion: sampling theory and multi-rate digital signal processing theory, compares the generation algorithm of NCO and its performance, and emphatically introduces the characteristics and advantages of Cordic algorithm. Then, the theory, structure and implementation method of every module of digital down-conversion based on FPGA are studied, such as: NCO (Digital controlled oscillator) CIC (integral comb filter) / HBF (half Band filter) / Fir low pass filter. In the design process, each module is simulated and debugged by calling Modelsim, and the spectrum analysis is done by Matlab to make it meet the design requirements. Finally, the EP4CE15F17C8 chip of Altera and AD9280 chip developed by AD Company are used in this design to generate a digital downconverter with input signal sampling frequency of 32MHz at 0.1-0.4MHz. It is tested at board level by spectrometer and signal generator.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN791
【参考文献】
相关期刊论文 前3条
1 姚亚峰;付东兵;杨晓非;;高速CORDIC算法的电路设计与实现[J];半导体技术;2008年04期
2 郝金光;冯宇;邱相艳;;Hogenauer CIC滤波器的算法研究及FPGA设计实现[J];电子元器件应用;2006年07期
3 贾雪琴;李强;王旭;李景宏;;用MATLAB在FPGA芯片中实现数字下变频设计[J];计算机仿真;2005年12期
，本文编号：2124991
本文链接：https://www.wllwen.com/kejilunwen/dianzigongchenglunwen/2124991.html
