FIR滤波器时延分析及其在信号融合中的应用

Time-delay analysis of FIR filter and its application to signal fusion

FIR(Finite Impulse Response)数字滤波器因其具有良好的线性特性而被广泛应用。但在利用FIR滤波器进行实际信号的滤波处理中,滤波后信号将会不可避免地产生明显的时延,影响滤波器的性能,从而限制了该滤波器在实际中的一些应用。为了解决这一问题,从FIR滤波器的相位特性出发,首先从理论上深入分析了FIR滤波器产生时延的原因,获得了FIR数字滤波器产生时延的内在规律,并给出了消除时延的数学模型。在上述研究基础上,将该模型应用到实际信号的提取及融合中,很好地消除了FIR滤波器滤波处理过程中的时延,也进一步验证了所给出的时延消除模型的正确性和有效性。

Finite impulse response（FIR）digital filter is widely used in digital signal processing due to its good linearity.However,an inevitably significant time-delay will be produced during the filtering process,which will affect the performance of the filter and limit its application in practice.In order to solve the problem,the reason causing time-delay was analyzed theoretically in this paper;firstly according to the phase characteristic of the FIR filter,then the internal relation between time-delay and the filter order is obtained.Based on the above,a mathematical model is established to eliminate the time-delay.Finally,this model is applied to the extraction and integration of the two actual signals,and the time-delay has been eliminated thoroughly during the digital filtering process,so as to prove that the time-delay model given in this paper is correct and effective.