A new design concept for wideband frequency-tunable and high-order MMIC microwave active recursive filters

This paper describes a new original microwave filter design concept using r ecursive principles and fully integrable in MMIC technology. To validate th is technique, a 7 GHz fixed center frequency filter with 2% bandwidth and a tunable filter with 2.5 GHz tuning range around 8 GHz have been successful ly implemented employing a 0.2 mu m Ga As P-HEMT monolithic technology. A m ulticellular approach, using a cascade association of first-order recursive cells, is also described. A tunable two-pole filter has then been realized by a cascade association of two tunable one-pole filters. (C) 2000 John Wi ley & Sons, Inc.