中频信号高速采样系统的设计与实现
毕业论文关键词 中频信号 高速采样 数字下变频 FIR滤波器 数控振荡器
Title Design of high-speed sampling system for IF signal Abstract Intermediate Frequency (IF) signal has been applied widely in communication, radar, image processing and other applications. In digital signal processing, high-speed sampling of IF signal has become a necessary requirement for signal processing, and is the basis of digital signal processing. This paper is designed to complete a high-speed sampling system of IF signal, the input signal is the carrier frequency 15MHz, 6MHz bandwidth frequency of the AM signal. The system main contains high-speed ADC, sampling control, DDC, and system simulation. ADC section designed with Altium Desinger, including the Single ended to differential circuit, Power circuit, Clock circuit, AD sampling circuit. The output sampling data is 12bit, and crawl demodulated waveform with Singaltap II. DDC part include NCO, Multipliers, FIR filter modules. ADC control program and the Verilog HDL program of DDC parts are writed in Quartuas II platform and simulated via Modelsim . Finally, By calling in MATLAB Simulink system-level simulation to verify the correctness of the program. High-speed AD sampling is the first step in digital signal processing, and is the basis of digital signal processing. Keywords Intermediate Frequency High-speed sampling Digital down conversion FIR NCO
目 次
1 绪论 . 1
1.1 研究目的及意义 1
1.2 国内外研究概况 1
1.3 数字信号处理结构 2
1.4 本文研究内容与章节安排 4
2 中频采样电路 . 5
2.1 总体方案设计 5
2.2 硬件模块 6
2.2.1 A/D采样模块 6
2.2.2 单端转差分电路 7
2.2.3 时钟电路 8
2.2.4 电源电路 9
2.2.5 A/D采样板 . 11
2.3 FPGA 开发系统 . 12
2.3.1 FPGA特点及开发流程 . 12
2.3.2 FPGA开发平台 . 13
2.4 本章总结 . 14
3 系统原理及模块仿真 15
3.1 采样原理 . 15
3.1.1 低通采样 . 15
3.1.2 带通采样 . 17
3.3 AM 调制信号 . 18