嵌入式Linux手持式音频测试仪的设计与实现

设计用于测量中波调幅广播发射机音频指标的基于嵌入式Linux的手持式音频测试仪,详细描述了测试仪硬件结构和软件程序,给出了信噪比、频率响应以及谐波失真等音频指标的测量算法。利用嵌入式Qt实现了人性化图形界面和频谱曲线绘制功能,并采用事先缓存的方法来避免图像闪烁,减少开销。实测结果证明设计思路完全可行。

Design and Implementation of Handy Audio Analyzer on Embedded Linux

The implementation of embedded Linux based handy audio analyzer which aims at measuring the audio parameters of AM broadcasting transmitters used in MW band is introduced in this paper. The design process of both hardware and software of the analyzer as well as methods of measuring signal to noise ratio, frequency response and harmonic distortion is described in detail. The technique of using Qt-embedded to render frequency spectrum is also showed in this paper. To avoid flickering and save computational resource during the rendering phase, off-screen buffering is introduced. The design is proved feasible by the experimental results.