高效低噪二阶状态空间数字滤波器误差谱成形

Error Spectrum Shaping in Computationally Efficient Low Noise Second-Order State-Space Digital Filters

本文给出误差反馈高效计算低舍入噪声(高效低噪)二阶线性状态空间(LSS)数字滤波器的设计方法。对窄带数字滤波,新结构比高效低噪原结构可降低噪声15dB,比原结构的最优LSS实现降低10dB。同时保持了原结构的运算高效性、溢出极限环稳定和低系数灵敏度等特性。用新结构并联实现高阶窄带椭圆滤波器,比用原结构和最优LSS结构的并联实现分别降低噪声13dB和9dB。

A computationally efficient low roundoff noise second-order linear state-space (LSS) digital filter with error feedback is designed. For narrow-band digitalfiltering, it is shown that the new structure, retaining the characteristics of theoriginal one, reduces roundoff noise by 15 dB and 10 dB comparing to the originalcomputationally efficient low roundoff noise second-order set and the optimalLSS realization respectively. Examples of high order narrow-band bandpass, lowpass and bandstop elliptic filter demonstrate that parallel realization of the new structures reduces 13 dB and 9dB in rounboff noise gain camparing with the parallel tealization of the original structures and the parallel realization of the optimal LSS structures respectively.