Chirp函数的NiosⅡ嵌入式实现

Realization of Chirp Fouction Based on Nios Ⅱ Embedded System

首先分析Chirp函数在频域上的一般特性,提出利用FPGA的嵌入式软核NiosⅡ处理器在嵌入式操作系统μC/OS-Ⅱ上实现Chirp的方法,即通过NiosⅡ处理器根据Chirp函数在频域上频率的跳变情况实时改变输出DDS(直接数字合成序列)模块的频率步进控制字的办法,控制DDS模块的频率输出,实现Chirp函数所要达到的扫频输出性的目的。通过在NiosⅡIDE编程环境中的Console窗口观察,该设计能很好地实现Chirp函数功能。

The characters of Chirp function in the frequency zone,and the method how to achieve the Chirp function in Nios Ⅱ software processor with embedded system μC/OS -Ⅱ are analysed. Changing the control_word of Digital Direct Synthesizer （DDS）with Nios Ⅱ software processor abey to Chirp function＇s jumping character in the frequency zone. So in this way,Chirp singnal source can be gained. This design can reach the fouction of Chirp fouction through simulation by the Nios Ⅱ IDE＇s Console window.