外插脉冲响应(EIR)滤波器设计技术是一种低复杂度有限冲击响应(FIR)滤波器设计技术,而基于主成份分析(PCA)的EIR(PCA—EIR)滤波器设计技术是一种有效(算法执行简单,效果较好)的EIR滤波器设计技术。PCA-EIR技术通过对由原型FIR滤波器系数组成的系数矩阵采用PCA技术进行降维来近似合成原型FIR滤波器,以达到降低原型滤波器硬件执行复杂度的目的。本文提出了一种简单有效的改进型PCA—EIR技术,其基本思想是将系数矩阵的前若干列向量保持不变,对剩余部分列向量组成的矩阵采用PCA技术进行降维来合成原型FIR滤波器。所提出改进型PCA—EIR技术的算法执行复杂度与传统PCA—EIR技术相当,且在滤波器频率响应指标基本相等的前提下,改进型PCA—EIR技术节省3.5%-17.5%乘法器和25.6%-51.6%加法器,从而进一步降低了FIR滤波器的硬件执行复杂度。
Extrapolated impulse response (EIR) filter design technique can be used to design finite impulse response (FIR) filter with low hardware implementation complexity. The principal component analysis (PCA) based EIR (PCA-EIR) filter design technique is an efficient EIR technique in view of its simple algorithm implementation and good perform-ance. The basic idea of PCA-EIR technique utilizes the PCA technique to lower the dimension of the coefficient matrix, which is formed from the prototype FIR filter coefficient. A simple yet useful modified PCA-EIR technique is proposed in this paper. The modified PCA-EIR technique keeps the first few column vectors of the coefficient matrix unchanged and uses the PCA technique to reduce the dimension of the matrix that is formed by the rest colunm vectors. The algorithm im-plementation complexity of the modified PCA-EIR technique and that of the PCA-EIR technique are almost the same. Pro-vided the frequency response performances are ahuost the same, the modified PCA-EIR technique can save 3.5%-17.5% multipliers and 25.6%-51.6% adders. Thus, by using our proposed modified PCA-EIR technique, the hardware imple-mentation complexity of the FIR filter can be further reduced.