Active impedance profile technique for selective tuneable active filter with gain

This paper deals with an approach for the design of microwave filters. This approach uses the active impedance profile (AIF) technique and can be considered as an extension of the classical loss compensation method with negative resistances. With this technique, we take benefit of the adequate imaginary part of an active one-port to control the bandwidth and selectivity of a passive filter response, while the real part simultaneously compensates for the losses in the passbands. We first explain this method and then, we apply it to the design of a selective tunable band-pass filter.