Abstract: An embodiment of the present invention provides an apparatus, comprising a tunable filter with a plurality of bond wires connecting voltage tunable dielectric capacitors to an RF ground and serving as inductors, wherein inductive coupling between the plurality of bond wires serve as coupling between resonators within the tunable filter. The voltage tunable dielectric capacitors may be integrated onto a single MgO chip thereby providing a complete set of tunable capacitors for a filter circuit in a low cost, compact package.

Abstract: An embodiment of the present invention provides an apparatus, comprising a multilayer filter including a first resonator on a first layer of dielectric material or low-temperature-co fired-ceramic, a second resonator coupled to the first resonator on a second layer of dielectric material or low-temperature-co fired-ceramic, a third resonator coupled to the second resonator and cross coupled to the first resonator, and wherein a voltage tunable dielectric capacitor is connected to at least one of the resonators to electrically tune the multilayer filter.

Abstract: An embodiment of the present invention provides an apparatus, comprising a tunable filter with a plurality of bond wires connecting voltage tunable dielectric capacitors to an RF ground and serving as inductors, wherein inductive coupling between the plurality of bond wires serve as coupling between resonators within the tunable filter. The voltage tunable dielectric capacitors may be integrated onto a single MgO chip thereby providing a complete set of tunable capacitors for a filter circuit in a low cost, compact package.

Abstract: An embodiment of the present invention provides an apparatus, comprising a varactor; and at least one external high-Q fixed capacitors combined with the varactor thereby improving the Q of the varactor. The at least one external high-Q fixed capacitor may combined in series with the varactor or in parallel with the varactor. Further, the varactor may be constructed of an internal low-tuning high-Q material with high-Q and large capacitance but low tuning range. The apparatus of one embodiment of the present invention may be incorporated into a 4-pole bandpass filter enabling Q improvement on the circuit performance or also may be incorporated into an amplifier or a voltage controlled oscillators or a phase shifters. Another embodiment of the present invention provides an apparatus, comprising a resonator and a varactor variably coupled into the resonator through an RF transformer, wherein by varying a coupling factor, the Q-factor and the tunability of the apparatus is capable of being affected.

Abstract: An embodiment of the present invention provides a voltage-controlled tunable filter, comprising a tunable ridged waveguide filter formed from a first ridged waveguide cavity coupled to a second ridged waveguide cavity thereby forming a resonator; and one or more tunable capacitors in at least one of said first or second waveguide cavity. The coupling between said first ridged waveguide and said second ridged waveguide may be via a coupling iris or ridged post and the one or more tunable capacitors may comprise a low loss tunable dielectric material and metallic electrodes with predetermined shape, size, and distance. In an embodiment of the present invention the one or more tunable capacitors may be MEMS tunable capacitors that are either parallel plate or interdigital topology.

Abstract: A voltage-controlled tunable suspended stripline planar filter, comprising a first resonator, the first resonator including at least one tunable capacitor and at least one PIN diode, and a second resonator coupled to the first resonator, the second resonator including at least one tunable capacitor and at least one PIN diode. The tunable filter may further comprising a low-pass section between a coupling line coupling said first and said second resonator and an input port and the first resonator may be coupled to the second resonator through proximity coupling. Further, in one embodiment of the present invention the at least one PIN diode in the first resonator may be two PIN diodes and the at least one tunable capacitor in the first resonator may be two tunable capacitors.

Abstract: A voltage-controlled tunable filter which includes a plurality of coaxial combline resonators and wherein at least one of said plurality of coaxial combline resonators includes at least one metallized through-hole. The coupling between adjacent resonators is obtained via an aperture formed on a common wall between the resonators, and is controlled by the aperture size and position. An input/output coupling metallization on at least one surface of said plurality of coaxial combline resonators is included as well as at least one tunable varactor associated with said plurality of coaxial combline resonators. An iris connects said plurality of coaxial combline resonators. The tunable dielectric capacitors can include a substrate having a low dielectric constant with planar surfaces and the substrate can be include a tunable dielectric film of low loss tunable dielectric material.

Abstract: A voltage-controlled tunable filter that comprises at least one coaxial combline resonator that includes at least one metallized through-hole, an input/output coupling metallization on at least one surface of said at least one coaxial combline resonator, at least one tunable varactor associated with said at least one coaxial combline resonator, and an inter-pole-and-port cross coupling component cross coupling a filter pole of said at least one combline resonator and said at least one input-output coupling metallization. At least one DC biasing point can be included to provide voltage to said at least one tunable varactor. In a preferred embodiment, the at least one tunable varactor is four tunable varactors and the least least one input/output coupling metallizations is two input/output coupling metallizations. The voltage-controlled tunable filter can be a monoblock voltage controlled tunable filter or a coaxial block voltage controlled tunable filter.

Abstract: A voltage-controlled tunable multilayer filter which comprises a first resonator on a first layer of dielectric material or low-temperature-co fired-ceramic; a second resonator coupled to said first resonator on a second layer of dielectric material or low-temperature-co fired-ceramic; a third resonator located on a third layer of dielectric material or low-temperature-co fired-ceramic coupled to said second resonator and cross coupled to said first resonator; an input transmission line connected to said first resonator; an output transmission line connected with said third resonator; and a variable capacitor in at least one of said resonators.