摘要
系统以单片机和FPGA为控制核心,实现了语音存储与回放系统。能够采集模拟语音信号以及耳机立体声信号,以ADPCM(自适应差分编码)的方式提高了存储器的利用率,语音存储时间可达2 min;基于短时傅里叶变换原理,实现了语音信号的频谱分析与实时显示。同时,利用立体声音频功放播放语音,每声道音量可调并具有静噪功能。此外,系统还采用预加重、去加重、抗混叠滤波等措施,有效地提高了信噪比。语音回放质量良好,存储时间较长。
With singlechip and FPGA as the cybernetics core, the system realizes voice storage and reply system. It can collect and simulate voice signals and stereo signals from earphone and lift utilization rate of memory by the use of ADPCM, which means the voice can be stored for more than 2 minutes. Based on the short-time Fourier transform principle, it can also achieve spectral analysis of voice signals and real-time display. Through using the stereo audio amplifier, each sound track can be adjusted and muted. Furthermore, some measures as pre-emphasis, de-emphasis and anti-aliasing filtering are used in this system to increase SNR efficiently and get good quality of the recorded voice for a longer time.
出处
《现代电子技术》
2013年第13期49-52,55,共5页
Modern Electronics Technique
基金
2012上海市重点科技攻关项目(11441901302)
