A novel frame error concealment scheme is proposed to improve the decoded audio quality of the receiver for transform coded excitation（TCX）audio codec.This scheme,which is a gain control approach based on the stabil...A novel frame error concealment scheme is proposed to improve the decoded audio quality of the receiver for transform coded excitation（TCX）audio codec.This scheme,which is a gain control approach based on the stability of linear predictive coding（LPC）filter,predicts the lost frames by utilizing the linear spectrum frequency and different continuous attenuation factor of different kinds of lost frames.Signal noise ratio（SNR）test and multiple stimuli with hidden reference and anchor（MUSHRA）test are conducted to evaluate the performance of this approach in adaptive multi-rate wideband plus（AMR-WB＋）audio codec.Compared with the original frame error concealment scheme,our scheme achieves better audio recovery quality in AMR-WB＋audio codec.展开更多
LC3plus(Low Complexity Communication Codec plus)协议中规定的模式选择机制用于支持音频解码器自适应选择最优丢包隐藏技术,该部分存在复杂的数学运算以及大量数据读写操作,增加了其在CPU中的运算延时。提出了以一种硬件架构用于协...LC3plus(Low Complexity Communication Codec plus)协议中规定的模式选择机制用于支持音频解码器自适应选择最优丢包隐藏技术,该部分存在复杂的数学运算以及大量数据读写操作,增加了其在CPU中的运算延时。提出了以一种硬件架构用于协调模式选择机制内部的相关数据交互,通过计算单元复用的方式,极大减小了模块消耗的逻辑资源。对所实现的选择模块进行了功能仿真与FPGA验证,测试结果表明,所设计的硬件模块处理结果符合LC3plus协议要求,且能以较小的硬件开销获得明显的处理加速。展开更多
针对超声波微弱信号接收和处理问题,进行了基于DSP(digital signal processor)开发板的采集前端分析与优化设计。采用下变频技术,充分利用了开发板上的音频编译码器实现微弱超声波信号采集。通过与普通ADC(analog-to-digital converter...针对超声波微弱信号接收和处理问题,进行了基于DSP(digital signal processor)开发板的采集前端分析与优化设计。采用下变频技术,充分利用了开发板上的音频编译码器实现微弱超声波信号采集。通过与普通ADC(analog-to-digital converter)采集方案的噪声系数进行对比,表明系统在微弱信号情况下,仍然可以获得较高的信噪比。该方案应用于一种便携式的超声波接收系统,使用户随时可以进行超声波信号的接收与处理工作。展开更多
基金Supported by the National High Technology Research and Development Program of China(863 Program)(2015AA016306)the Foundation of Outstanding Middle-aged and Young Scientific and Technological Innovation Team Program of Department of Education of Hubei Province(T201516)the Foundation of Department of Education of Hubei Province(Q20132207)
文摘A novel frame error concealment scheme is proposed to improve the decoded audio quality of the receiver for transform coded excitation（TCX）audio codec.This scheme,which is a gain control approach based on the stability of linear predictive coding（LPC）filter,predicts the lost frames by utilizing the linear spectrum frequency and different continuous attenuation factor of different kinds of lost frames.Signal noise ratio（SNR）test and multiple stimuli with hidden reference and anchor（MUSHRA）test are conducted to evaluate the performance of this approach in adaptive multi-rate wideband plus（AMR-WB＋）audio codec.Compared with the original frame error concealment scheme,our scheme achieves better audio recovery quality in AMR-WB＋audio codec.
文摘LC3plus(Low Complexity Communication Codec plus)协议中规定的模式选择机制用于支持音频解码器自适应选择最优丢包隐藏技术,该部分存在复杂的数学运算以及大量数据读写操作,增加了其在CPU中的运算延时。提出了以一种硬件架构用于协调模式选择机制内部的相关数据交互,通过计算单元复用的方式,极大减小了模块消耗的逻辑资源。对所实现的选择模块进行了功能仿真与FPGA验证,测试结果表明,所设计的硬件模块处理结果符合LC3plus协议要求,且能以较小的硬件开销获得明显的处理加速。
文摘针对超声波微弱信号接收和处理问题,进行了基于DSP(digital signal processor)开发板的采集前端分析与优化设计。采用下变频技术,充分利用了开发板上的音频编译码器实现微弱超声波信号采集。通过与普通ADC(analog-to-digital converter)采集方案的噪声系数进行对比,表明系统在微弱信号情况下,仍然可以获得较高的信噪比。该方案应用于一种便携式的超声波接收系统,使用户随时可以进行超声波信号的接收与处理工作。
