基于FPGA的函数信号发生器设计.doc

图书分类号： 密 级： 摘要 函数信号发生器是各种测试和实验过程中不可缺少的工具，在通信、测量、雷达、控制、教学等领域应用十分广泛。随着我国经济和科技的发展，对相应的测试仪器和测试手段也提出了更高的要求，信号发生器己成为测试仪器中至关重要的一类。 本文在探讨函数信号发生器几种实现方式的基础上，采用直接数字频率合成（DDS）技术实现函数信号发生器。在对直接数字频率合成（DDS）技术充分了解后，本文选择以Altera公司生产的FPGA芯片为核心，以硬件描述语言Verilog HDL为开发语言，设计实现了可以产生任意波形（以正弦波为例）和固定波形的（以方波和锯齿波为例）的函数信号发生器。文中详细阐述了直接数字频率合成（DDS）、波形产生以及调幅模块的设计，并给出了相应的仿真结果。 本文最后给出了整个系统的仿真结果，即正弦波、方波、锯齿波的波形输出。实验表明，用现场可编程门阵列（FPGA）设计实现的采用直接数字频率合成（DDS）技术的函数信号发生器，克服了传统方法的局限，实现了信号发生器多波形输出以及方便调频、调幅的功能。 关键词 函数信号发生器；直接数字频率合成；现场可编程门阵列；Verilog HDL Abstract Function Generator is an indispensable tool in a process of various tests and experiments. It is widely used in communication, measurement, radar, control, teaching and other fields. With the development of Chinas economic and technological, the corresponding test equipment and test methods are also put forward higher requirements, and the signal generator has become a vital test instrument. The article examines the several implementations of the function generator. And it has achieved the function generator which is completed by direct digital frequency synthesis (DDS) technology . Through understanding the direct digital frequency synthesis (DDS) technology, this paper chose to the Altera Corporations’ FPGA chips as the core of design. The function generator which can produce sine, square wave, sawtooth wave was designed. It also used hardware description language Verilog HDL as development language. The paper described the design of the main module, such as direct digital synthesizer (DDS), waveform generation and modulation module. And the corresponding simulation results were also presented. At last, the simulation results of the whole system were presented, that is, sine, square, sawtooth waveform has been carried out. Experiments show that the function generator based on FPGA and direct digital frequency synthesis (DDS)technology has overcame the limitations of traditional methods and achieved a signal generator which can generate multiple wa