离散小波改进算法在机动车辆换挡信号降噪中的应用

针对机动车辆换挡信号中存在大量强电磁及环境振动噪声的问题,同时考虑到实时性和硬件实现性能的需求,基于最小带宽离散小波算法,提出了简化的、适用于工程实现的小波分解层数确定方法;然后利用初始阈值对各层小波系数进行分类,利用各层中各类系数均值差的模及均方差为依据,设计了各层阈值的自适应迭代确定算法,同时改进了阈值的量化函数。仿真对比试验和应用测试结果表明,该算法具有较好的降噪效果,适用于机动车辆的相关信号检测与降噪。

Improved Discrete Wavelet Transform Algorithm with Applications to Shift Signal De-nosing of Motor Vehicles

Aiming at the strong electromagnetic and environment vibration noise which exist in the shift signals of motor vehicles,and considering the requirements of real -time and hardware implementation,this paper proposes the simplified method of determining the layer number of wavelet decomposition based on the minimum bandwidth discrete wavelet algorithm. Then,the initial threshold is used to classify the wavelet coefficients in each layer classification. Moreover,the each layer threshold adaptive iteration algorithm is designed in consideration of mean differences and square errors of coefficients in each layer,and the threshold quantization function is improved. Finally,simulation and application contrast testing results indicates that the algorithm has good noise reduction effect,and is suitable for related signal detection and noise reduction of motor vehicles.