A Switched Capacitor Based Realization of Fractional Order Low-Pass Filters

In present days, all the fundamental concepts and techniques of signal processing and control theory is being extended towards fractional order systems. In this paper, we considered a family of fractional order low pass filters. Using the concepts of fractional order calculus, they are approximated uptoa satisfactory level. We then took these approximated transfer functions and realised them using operational amplifiers and passive components(resistors and capacitors). The resistors were further approximated by switched capacitor(SC) arrangements. The switched capacitor based filters are simulated in Or CADp SPICE platform. These results were matched with their corresponding theoretical responses simulated in MATLAB. The broad purpose of this work is to propose a novel technique to design fractional order filters which can be used in discrete time analog signal processing applications or control applications. The goal behind using SC arrangements was to make the integration of both analog and digital functions possible in a single chip.