摘要:
可变载频带限信号的重采样,一般归结为按转换比P/Q(P为内插比,Q为抽取比)对原采样序列做内插和抽取。当P值很大时,需要多路内插滤波器,由于抗镜像的需要,滤波器系数矩阵非常庞大,使得高阶重采样难以实现。该文提出一种多项式近似滤波器的方法,用一组低阶多项式近似内插滤波器系数矩阵,简化了滤波器的结构,运算效率高,且内插延迟可任意改变。计算机仿真的结果表明:该结构适用于可变延迟的高阶带限内插滤波器。在一定条件下,误差在容许的范围之内。
Abstract:
The resampling of the passband signal with variable frequency is likely implemented by interpolating and decimating the original sequence according to the converting ratio (P/Q). When the value of P is very large, the multiple interpolating filters will be required, and due to anti-image frequency filtering, the coefficient matrix of filters are very complex, which results in the resampling difficult to implement. This paper presents a method of the Polynomical Approximate Filtering (PAF). It uses a group of coefficient matrixed for low-order PAF, with efficient operation and variable interpolating delay. The computer simulation show that it is suitable to the high order interpolating filters with variable delay. In some cases, the tolerance is within the allowable range.