Improvement of gain compression in microwave lumped and transversal bandpass filters

A new gain compression improvement technique for the microwave lumped and transversal bandpass filter is proposed in this paper. This technique uses active feedback for linearization of the main transversal element allowing an overall filter´s P1dB elevation. In order to verify the proposed method, a prototype L-band microwave lumped and transversal bandpass filter with 2 GHz center frequency and 15% FBW is designed and fabricated. The experimental result exhibits an overall noise figure of 4.4 dB and reports a 6.5 dB P1dB improvement of the proposed filter when compared with a conventional structure.