초록 ▼

A tunable filter (400) provides dual injection mode operation over a continuously tunable frequency range (500). A combination of mirrored series resonant circuits (432, 446) tuned through varactors (434, 448) allows the frequency response to shift. The use of a series capacitor and shunted inductor

A tunable filter (400) provides dual injection mode operation over a continuously tunable frequency range (500). A combination of mirrored series resonant circuits (432, 446) tuned through varactors (434, 448) allows the frequency response to shift. The use of a series capacitor and shunted inductor (430, 428), (444, 442) mirrored onto each series resonator (432, 446) provides both high-side and low-side injection protection.

대표청구항 ▼

[ What is claimed is:] [1.] An electrically tunable bandpass filter, comprising:a first resonator formed of a first series resonant circuit;a first series capacitor and shunted inductor (LC) combination coupled to the first resonator;a second resonator formed of a second series resonant circuit;a se

[ What is claimed is:] [1.] An electrically tunable bandpass filter, comprising:a first resonator formed of a first series resonant circuit;a first series capacitor and shunted inductor (LC) combination coupled to the first resonator;a second resonator formed of a second series resonant circuit;a second series capacitor and shunted inductor (LC) combination coupled to the second resonator, the first LC combination and second LC combination providing a filter response having substantially symmetrical low-side injection protection and high-side injection protection;a first coupling element coupled between the first and second resonators; anda second coupling element coupled between the first and second shunted inductors.