积分梳状(CIC)滤波器因结构简单和良好的抗混叠性,被应用于各种信号处理系统中。 针对传统CIC 滤波器通带失真较大和阻带衰减较小的问题,通过分析CIC滤波器的特点,提出了一种切比雪夫梳状补偿滤波器(C-CIC)。 MatLab仿真结果表明,与传统CIC、内插二阶多项式级联积分梳状滤波器(ISOP-CIC)和余弦积分梳状滤波器(CIC-COSINE)相比,当CIC级 联的级数相同时, C-CIC滤波器在频率fc处通带幅值的失真和频率fa处的阻带衰减都得到了较大改善。经过FPGA的设计工具 Quartus仿真得知,达到相同的幅频特性时, C-CIC滤波器消耗的片上资源少于ISOP-CIC和CIC-COSINE滤波器。C-CIC滤波器可以更好地应用于波长 调制-可调谐二极管激光吸收光谱(TDLAS)系统中。

For the advantage of simple structure and good anti-aliasing, cascaded integrator comb (CIC) filter has been widely used in a variety of signal processing systems. Aiming at the problem of large passband distortion and small stopband attenuation of the traditional CIC filter, a Chebyshev cascade integral comb (C-CIC) filter is proposed by analyzing the characteristics of CIC filter. The simulation results using MatLab show that compared with the traditional CIC, interpolated second-order polynomial cascade integral comb filter (ISOP-CIC) and cosine integral comb filter (CIC-COSINE), the C-CIC filter has a large improvement in passband distortion at frequency fc and stopband attenuation at frequency fa when the number of CIC cascades is the same. According to the Quartus simulation, design tool of FPGA, the C-CIC filter consumes less on-chip resources than the ISOP-CIC and CIC-COSINE filters when the same amplitude-frequency characteristics are achieved. It is indicated that the C-CIC filter can be better used in tunable diode laser absorption spectrometer (TDLAS) system.