基于小波包最优基的语音信号压缩方法

提出了基于方差准则的小波包最优基压缩方法。首先选择一个合适的小波函数及分解层次对语音信号进行小波包分解。然后基于方差准则确定小波包最优基,保留语音信号的重要特征,实现信号压缩。最后对小波包最优基中的小波系数进行量化、编码,以便于信号在信道中传输。在接收端进行译码,重构压缩后的语音信号,观察压缩效果。实验中对语音信号采用不同方法进行了压缩实验,验证了本文算法的可行性。实验结果表明,本文算法的搜索量小,易于实现,压缩效果比较明显。

基于子波变换的语音信号压缩

基于子波变换的多分辨分析特性 ,直接采用Mallat多层分解的低频系数进行语音信号压缩 ,并进行了计算机仿真 ,结果表明该方法是有效的、可行的 .

低功耗精确定位语音对讲信息矿灯设计

针对煤矿现场智能化矿山建设及提升井下作业人员生命安全实际需要,分析传统信息矿灯成本高、功耗大,WiFi无线射频置于灯头等缺点,设计一种低功耗、低成本精确定位语音对讲信息矿灯;通过对UWB定位技术和WiFi无线通信技术休眠机制的研究,延长了矿灯使用寿命;对语音信号压缩编码算法研究,将无线射频与灯头分离,采用单芯片声码器,降低了成本;定位语音对讲信息矿灯不仅实现高精度定位功能,同时,在危险状态下可以紧急呼救、群组撤离、各种灾害可靠逃生路线信息导播等,为矿工井下作业提供更安全有力的保障。

Compression and reconstruction of speech signals based on compressed sensing

Based on the approximate sparseness of speech in wavelet basis,a compressed sensing theory is applied to compress and reconstruct speech signals.Compared with one-dimensional orthogonal wavelet transform(OWT),two-dimensional OWT combined with Dmeyer and biorthogonal wavelet is firstly proposed to raise running efficiency in speech frame processing,furthermore,the threshold is set to improve the sparseness.Then an adaptive subgradient projection method(ASPM)is adopted for speech reconstruction in compressed sensing.Meanwhile,mechanism which adaptively adjusts inflation parameter in different iterations has been designed for fast convergence.Theoretical analysis and simulation results conclude that this algorithm has fast convergence,and lower reconstruction error,and also exhibits higher robustness in different noise intensities.