摘要
基于直接数字频率合成技术(DDS),以LPC2132单片机和AD9852芯片为核心,并辅以外围模拟电路,设计了信号发生器。信号发生器由单片机系统、键盘液晶显示模块、波形发生模块和功率放大模块组成,实现了AM、FM、PSK、ASK、FSK信号调制。其中功率放大模块提高了输出波形质量并增强了其带载能力。应用嵌入式操作系统μC/OS-Ⅱ,减少了系统的软件设计周期,并为各个任务的分配提供了良好的开发环境,体现了实时操作系统的优越性。
The system designed to construct a waveform generator was based on direct digital synthesis, with LPC2132 and AD9852 as the key, complemented by necessary analog circuit. Sine waveform generator included four parts： LPC2132 minimal system, key- board-LCD-display interface module, wave generator, power amplifier module. It achieved AM, FM, PSK, ASK, FSK signal modulation. The power amplifier circuit increased the quality of the output waveform and its loading capacity. Applied with the embedded operating system μC/OS-Ⅱ, the software designing period was reduced. In addition, the μC/OS-Ⅱ system provided a favorable exploring environment for the distribution of each task, thus shows the superiority of the real-time operating system.
