强噪环境下分频段数字音频信号精细化采集研究  

Research on refined acquisition of divided frequency digital audio signals in strong noise environment

作　　者：哈筝 HA Zheng(School of Music,Shanxi University,Taiyuan 030006,China)

机构地区：[1]山西大学音乐学院,山西太原030006

出　　处：《现代电子技术》2024年第11期64-68,共5页Modern Electronics Technique

摘　　要：在强噪环境下,为了获取高质量、低失真度的数字音频信号,提出一种强噪环境下分频段数字音频信号精细化采集方法。通过麦克风设备获取音频信号,利用LM4550芯片对其作采样、编码等处理后生成数字音频信号,基于AC-97单元接收数字音频信号,利用频段分割器对其作频带分解,获得互不重叠子频段数字音频信号。采用多窗谱谱减法对其去噪,利用数据通信接口将其传输给LM4550芯片,在完成模拟信号转换后,通过耳机输出,实现数字音频信号精细化采集。实验结果表明,该方法处理后的各子频段数字音频信号有用信息得以完整保留,并提高了信号波形的规整度和规律性,强噪声环境下数字音频信号的PESQ指标达到4.08以上,最大失真度为3.74%。In order to obtain digital audio signals with high-quality and low distortion in a strong noise environment,a refined acquisition method for divided frequency digital audio signals in a strong noise environment is proposed.Audio signals are obtained by the microphone device.Chip LM4550 is used for the sampling,encoding and other processing of the obtained audio signals to generate digital audio signals,which is received on the basis of AC-97 units.Frequency band dividers are utilized to perform frequency band decomposition to obtain non overlapping sub band digital audio signals,which are then denoised by multi-window spectral subtraction,and then transmitted to the chip LM4550 by a data communication interface.After completing the analog signal conversion,it is output by headphones to achieve refined digital audio signal acquisition.The experimental results show that the useful information of various sub frequency bands of digital audio signals processed by the proposed method can be preserved fully,and the regularity of the signal waveform can be improved.In addition,the index PESQ(perceptual evaluation of speech quality)of digital audio signals in a strong noise environment reaches 4.08 or above,with a maximum distortion of 3.74%.

关 键 词：强噪环境 分频段 数字音频信号 FPGA 频段分割器 多窗谱谱减法 通信接口 模拟信号 

分 类 号：TN914-34[电子电信—通信与信息系统]