预加重及去加重在无线音频设备中的应用

Application of Pre-emphasis and De-Emphasis in Wireless Audio Device

针对在测量车载收放音机电压频率特性参数时,发现采用预加重电路和未采用预加重电路测量时,音频信号较高频率的电压衰减分贝数差别比较大的问题,首先介绍了测量汽车收音机电压频率特性指标所用到的相关测量仪器、测量方案、测量依据标准,其次分别介绍了采用预加重电路和未采用预加重电路时测量得到的电压频率特性结果,最后分析了预加重及去加重理论原理。

Pre - emphasis circuit and non pre - emphasis circuit are adopted in the measurement of voltage frequency characteristics for car radio machine. The voltage attenuation of the high frequency for the audio signal in the above two situ- ation is quite different. According to the problem, test instruments, test scheme and test standards are introduced firstly, then the test result of voltage frequency characteristics about the pre - emphasis circuit and non pre - emphasis circuit is intro- duced. Finally, the theory of pre - emphasis and de - emphasis is analyzed, and the importance of the theory in the practice is formulated.