基于FPGA的软件无线电数字下变频技术的设计

发布时间：2018-05-05 08:32

本文选题：软件无线电 + 数字下变频　；参考：《广东工业大学》2015年硕士论文

【摘要】：软件无线电(SDR,Software Defined Radio)作为一个高度可配置的硬件平台,通过软件方式来实现各种功能,是当前通信领域研究的热点。数字下变频技术(DDC,Digital Down Converter)作为软件无线电的核心技术之一,使A/D采样的中频信号搬移到基带,最终目的是完成对信号的提取,其性能的优劣将决定整个软件无线电系统的性能。本文针对软件无线电数字下变频技术展开研究,本文的主要研究包括以下几个方面的内容：1.总结了软件无线电数字下变频技术的研究背景,技术特点以及国内外的研究状况。分析了数字下变频的数字信号处理理论,多速率信号处理理论。2.在掌握数字下变频基本原理的基础上,分析研究了数字下变频各关键模块的技术的方法,包括数字控制振荡(NCO,numerically controlled oscillator)和积分梳状(CIC, Cascaded Integrator-Comb)滤波器、半带(HB,Half-Band)滤波器、以及有限长单位冲激响应(FIR, Finite Impulse Response)滤波器组成的滤波器组。3.使用FPGA完成了对数字下变频各模块的设计,通过模型化的设计理念在Altera公司的系统级设计工具DSP builder中对数字下变频器各模块进行了具体设计,首先运用CORDIC算法的思想来设计实现数字振荡器,采用Altera公司提供的IP CORE实现简单,同时频率分辨率高。片内乘法器实际上起着混频器的作用,在硬件上实现简单。通过采用Matlab FDAtool工具箱与IP核调用的方式在数字滤波器设计,数字抽取滤波器采用CIC滤波器和半带滤波器的级联形式,通过采用分布式算法来实现FIR整形滤波。最后对各个模块进行了系统级仿真测试,测试表明每个模块都能正常工作,满足设计要求。通过用FPGA实现了软件无线电中的关键技术—数字下变频,基于模型化的设计理念,可以根据不同系统的要求来实现实现数字下变频功能,这将成倍的提高开发效率与降低开发难度。因此用FPGA来实现数字下变频具有实际意义和研究价值。
[Abstract]:As a highly configurable hardware platform, software radio (SDR) can realize various functions by software, which is a hot topic in the field of communication. As one of the core technologies of software radio, digital down conversion (DDC / D Digital Down conversion) technology makes the if signal of A- / D sampling move to baseband. The ultimate goal is to complete the signal extraction. The performance of the whole software radio system will be determined by its performance. In this paper, the digital downconversion technology of software radio is studied, the main research of this paper includes the following aspects: 1. This paper summarizes the research background, technical characteristics and domestic and international research status of software radio digital down conversion technology. The digital signal processing theory of digital downconversion and the theory of multi-rate signal processing are analyzed. On the basis of mastering the basic principle of digital down-conversion, this paper analyzes and studies the technical methods of the key modules of digital down-conversion, including digitally controlled oscillators, numerically controlled oscillators, integral comb CIC-Comb filters, half-band HBV-Half-Bandfilters, etc. And the filter bank. 3. 3, which is composed of finite length unit impulse response (fire, Finite Impulse response) filter. FPGA is used to complete the design of each module of digital down-conversion, and each module of digital down-converter is designed in the system-level design tool DSP builder of Altera Company through the model design idea. Firstly, the digital oscillator is designed and implemented by using the idea of CORDIC algorithm. The IP CORE provided by Altera is simple and has high frequency resolution. In fact, the intra-chip multiplier acts as a mixer and is easy to implement in hardware. The digital filter is designed by using the Matlab FDAtool toolbox and IP core call. The digital decimation filter adopts the concatenated form of CIC filter and half-band filter, and the FIR shaping filter is realized by using distributed algorithm. Finally, the system level simulation test of each module shows that each module can work normally and meet the design requirements. Digital down conversion (DDC), the key technology of software radio, is realized by using FPGA. Based on the design concept of modeling, the function of DDC can be realized according to the requirements of different systems. This will multiply the development efficiency and reduce the difficulty of development. So using FPGA to realize digital downconversion has practical significance and research value.
【学位授予单位】：广东工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN791

【相似文献】