Design and simulation of low-noise bandpass filter by using active capacitance circuit

Abstract

This article aims to design and simulation of the active capacitance circuit and its Negative resistance feature. It also suggests a novel method in the field of active filters which is based on an active capacitance circuit. ADS2010 software was employed to perform the simulations. It is demonstrated via the simulated results that the proposed RF active filter is capable of being applied to the narrow bandpass filter (BPF) design, and also is stable and possesses Low-noise features. The frequency range within which the circuit shows a negative resistance is 2GHz to 6.8GHz, and the center frequency is 5.5GHz. The gain is obtained 1dB at the center frequency with a quality factor (Q) of 26. At the center frequency, the noise-figure of active filter is 1.925 dB. Generally, the K factor is larger than 1 and the circuit is entirely stable within the frequency range.