GaAs integrated RC active filters with high-selectivity bandpass and low-selectivity bandstop responses

Abstract

This paper presents bandpass and bandstop second-order RC active filters integrated on GaAs and operating above 1 GHz. In particular, high-selectivity bandpass filters have been investigated and two structures are proposed. These structures combine high selectivity and low sensitivity more easily than classical filters when only low-gain elements are available, and they may therefore also be useful at high frequencies. The quality factor of the proposed GaAs implementations of these structures can be tuned up to 50 typically when low-accuracy tuning biases are used.