【摘要】 研究了一种数字全通滤波器的设计方法。对于一个平稳的全通滤波器,其分母多项式一定具有最小相位。该方法是基于最小相位滤波器的复倒谱系数和其群迟延函数以及其系统函数之间的关系,通过一个非线性的递归方程求解分母多项式的系数。由全通滤波器的特性已知,分母系数可以完全决定全通滤波器的传递函数。仿真结果表明这种方法能够使所设计滤波器的群延迟特性在整个频率范围内以近似理想的群延迟特性存在。并结合实现提出了一种用FIR逼近IIR的方法。更多还原

【Abstract】 A method for the design of digital all-pass filters using cepstral coefficients is introduced.The denominator polynomial of a stable all-pass filter is certain to have a minimum phase.Based on the relationship between the group delay function and the cepstral coefficients,the denominator polynomial coefficients can be determined through a nonlinear recursive difference equation.The characteristics of all-pass filters reveal that the denominator coefficient alone can determine the transfer function of an all-pass filter.Simulation results show that a desired group delay characteristic can be realized approximately.A method of using FIR filters to approximate IIR filters is presented.更多还原