改进的基于MELP的非连续传输语音编码算法  

Improved discontinuous transmission speech coding algorithm based on MELP

作　　者：李强[1] 谢虹恩 

机构地区：[1]重庆邮电大学信号与信息处理重庆市重点实验室,重庆400065

出　　处：《重庆邮电大学学报（自然科学版）》2014年第5期636-641,共6页Journal of Chongqing University of Posts and Telecommunications(Natural Science Edition)

基　　金：国家高技术研究发展计划("863"计划)(2012AA01A508);2012年重庆邮电大学大学生科研训练计划(A2012-68)~~

摘　　要：为了提高语音通信传输带宽的利用率,提出了一种基于混合激励线性预测声码器的非连续传输方法。利用话音激活检测算法将接收到的语音信号区分为话音帧和静音帧,在话音帧向静音帧转换时引入过渡帧,话音帧和过渡帧采用正常码率进行编码,静音帧采用较低码率将其编码为静音描述(silence descriptor,SID)帧,并采用非连续的方式发送SID帧,SID帧的发送频率根据静音帧中背景噪声的特征参数的波动情况自适应调整。仿真实验表明,该方法在传输静音段信号时具有较好的自适应性,合成的背景噪声在主观听觉上具有良好的舒适性和连续性。In order to improve the utilization of transmission bandwidth in voice communication, this paper proposes a dis- continuous transmission method based on mixed excitation linear prediction （MELP） vocoder. Firstly, by using the algo- rithm of voice activity detection （VAD）, the received signal is divided into voice frame and mute frame. The transitional frame is introduced when the voice frame is converted to mute frame. Voice frames and transitional frames are encoded at a normal rate, but mute frames are encoded into silence description （SID） frame at a lower rate, which is sent by a method of discontinuous transmission mode. The transmission frequency of SID frame is adjusted automatically according to the fluctuation of characteristic parameters of background noise in mute frames. Simulation results show that this method has better adaptability in the transmission of mute signal and the synthesized background noise presents good comfort and conti- nuity in the auditory perception.

关 键 词：混合激励线性预测 非连续传输 话音激活检测 静音描述帧 

分 类 号：TN912.3[电子电信—通信与信息系统]