Abstract: An HTS microwave circuit has two layers formed with metallic film on a substrate. One layer has a first circuit and another layer has a second circuit, the two circuits being coupled to one another. The second circuit has elements that are incompatible with HTS material such as MEMS technology and flip-chip technology. A microwave switch has a first layer that can carry an RF signal and a second layer that has switch elements that are controlled by a DC. signal. The RF signal and DC signal are isolated from one another. The switch elements include various technologies including a narrow HTS strip. A single layer HTS microwave switch can also be utilized where the switch element is a narrow HTS line. A method of combing HTS technology with incompatible technologies into one device is provided.

Abstract: A fully monolithic cross-point switch matrix overcomes the isolation problems between unconnected ports of the prior art. An Isolation Enhancement Network (IEN) is connected between each of the input and output transmission lines at each of the cross-points. The switch matrix is comprised of a tiled interconnection of M×N of the 1×1 switch/IEN (SIEN) cells, where N and M are the number of input and output ports respectively. Each of the SIEN cells can be independently configured into one of two operating modes, connected or unconnected. The switching element is configured to provide a high isolation path between the input and output lines in the unconnected mode of operation. In this case, a small fraction of the input signal injected at the input port appears at the output port. This output signal is comprised of two components.

Abstract: A high power superconductive circuit has a thin film of high temperature superconductive material on a substrate. The circuit is formed from wafers that are placed into corresponding grooves within the substrate and held in place by adhesive. The grooves can be blind grooves or they can be through holes and the wafers will have a corresponding size and shape. The wafers include a thin film of high temperature superconductive material and can form resonators or an input or output. A circuit constructed in this manner has a relatively high power handling capability compared to circuits created by etching.

Abstract: A redundancy combiner assembly has two amplifiers connected in parallel along a waveguide path to a hybrid. The hybrid is connected through a transfer switch to an antenna. The hybrid contains a movable coupling plate. The coupling plate has a coupling array to allow combining of signals of the amplifiers in one position. When one of the amplifiers fails, the coupling plate is replaced by a metal wall and the output from the failed amplifier is directed by the switch to a dump load while the output from the operating amplifier is directed to the antenna. The assembly is controlled by a controller, which monitors the amplifiers and controls the movement of the coupling plate and the switch.

Abstract: A microwave filter has a plurality of resonators and at least one transmission line mounted on a substrate having a ground plane. The filter can have input and output couplings that are transmission lines formed on the substrate or it can have input and output probes. The resonators have one or more gaps extending entirely therethrough, the gaps splitting the resonators into two or more slices. The transmission lines extend into the gap to couple energy into or out of a resonator or between two adjacent resonators. The transmission lines can have tapered ends or can be located off center so that they are closer to one side of a gap than to another side.

Abstract: A device for changing the operating frequency of a microwave filter is mounted in a wall of a cavity of the filter. The device has a bellows that is located inside the cavity. The bellows contains an elongated member that extends outside the cavity to an actuator. The actuator can be temperature dependent and moves the elongated member either further into or further out of the cavity as desired. An interior end of the elongated member can be connected to the bellows or it can simply be in contact with the bellows without being connected. When the elongated member is in contact with the bellows and is not connected, when the elongated member moves outward, the bellows will return to a rest position due to its inherent spring. The bellows is sealed from an interior of the cavity. Filters using the device have one device located primarily for each mode in each cavity of the filter.

Abstract: A high power high temperature superconductive circuit for use in various microwave devices including filters, dielectric resonator filters, multiplexers, transmission lines, delay lines, hybrids and beam-forming networks has thin gold films deposited either on a substrate or on top of the high temperature superconductive film. Alternatively, other metal films can be used or a plurality of dielectric films can be used or a dielectric constant gradient substrate can be used. The use of these materials in a part or parts of a microwave circuit reduces the current density in those parts compared to the level of current density if only high temperature superconductive film is used. This increases the power handling capability of the circuit.

Abstract: A microwave circular waveguide cavity and filter containing said cavity has a circular iris mounted transversely within the cavity. The iris has an eccentrically located circular aperture that is sized and located to control coupling between modes resonating in the cavity. The cavity can be a dual mode cavity, a triple mode cavity or a higher mode cavity. In a method of constructing such a cavity, coupling can be controlled by choosing from a number of variables including the size of the aperture, the offset distance, the inclination angle, the thickness and the location of the iris within the cavity.

Abstract: A planar dual mode filter has one or more resonators with L-shaped sections that are oriented back to back to one another. The filter can be constructed by adjusting the size of a gap between the back to back sections and adjusting the offset distance between adjacent sections. Further, coupling between adjacent resonators can be controlled by adjusting a distance between the adjacent resonators. The filters can be co-planar, stripline, suspended microstripline or microstripline. The filters have a film on a substrate with a ground plane. The film can be gold, silver or copper or it can be a ceramic material that becomes superconductive at cryogenic temperatures.

Abstract: A low loss surface acoustic wave (SAW) filter and method of operation thereof uses non-sequential coupling and, more particularly, cross-coupling to achieve good rejection characteristics with low loss. Strips of metallization are used with a circuit formed of a thin film of metallization. The strips are oriented parallel to an edge of each resonator being cross-coupled. In a six resonator filter, the second and fifth resonators are cross-coupled.

Abstract: Microstrip/stripline transmission lines have a plurality of strips on a substrate where strips are separated by a gap. This arrangement results in a reduced maximum current density compared to previous transmission lines with the same power handling capability. The strips can have the same width or different widths. The gaps can have the same width or different widths. The transmission lines can be used in filters and resonators and can be made of high temperature superconductive materials.

Abstract: A temperature compensated microwave filter has end caps and irises that each contain a projection that extends into a cavity to reduce the volume change of the cavity that would otherwise occur with changes in temperature due to an expansion or contraction of the side walls. The end caps and irises are formed from a single material. The material has a more positive coefficient of thermal expansion than the coefficient of thermal expansion of the side walls of each cavity. While one material is used to make up each end cap or iris, it is not necessary that the same material be used for all of the end cap and iris components.

Abstract: A low insertion loss, wide bandwidth, microwave switch has a superconducting transmission line that can reversibly go from a superconducting state to a normal state by the application of a DC voltage. When in the normal state, the switch is "off" and microwave signals are attenuated. To reduce the voltage necessary to cause switching, the width of the transmission line is decreased. This decrease in voltage is accomplished in a controlled manner so that there are no spurious reflections produced on the line, resulting in a wide operating bandwidth. Previous microwave switches use other means to switch between superconducting and normal and suffer from disadvantages such as relatively slow switching time, complexity or narrow bandwidths as a result.

Abstract: A microwave bandpass filter has a planar configuration formed in microstrip or stripline where a circuit is printed onto a substrate. The filter has at least two patch resonators with a T-shaped coupling path extending between the two resonators. In a further embodiment of the invention, one or more resonators is isolated from other resonators in the filter by being located in a compartmentalized housing or separate housings to eliminate undesirable coupling between a resonator in one compartment and a resonator in another compartment. The filter of the present invention has improved performance characteristics over previous patch resonator filters.

Abstract: A CCD camera system has reconfigurable hardware and is controlled by a computer having reconfigurable software. The computer can receive and transmit signals between the system and a ground station. The hardware and software are reconfigurable based on signals from the ground station.

Abstract: A microwave filter has a plurality of resonant cavities with each cavity containing a dielectric resonator. There are self-equalizing probes or self-equalizing apertures located between some of the cavities. A circulator is connected to an output of the filter. The circulator has an input/output which is connected to an equalizer. The equalizer contains a dielectric resonator that is slightly different from the dielectric resonators of the filter to permit the equalizer to be tuned at a slightly different frequency from the filter. The equalizer and self-equalizing probes or apertures are capable of being operated to reduce a dispersive slope of the filter. The filter can operate in a single mode or a dual mode. The electrical performance of the filter is superior to prior art filters, particularly in the wideband versions because the dispersive slope is reduced.

Abstract: The invention relates to a single mode multi-cavity microwave filter that includes a housing formed with a plurality of walls which define at least two rows of side-by-side dielectric loaded cavities, wherein sequential cavities are coupled to one another via slots formed in the walls therebetween and at least one pair of non-sequential adjacent cavities are coupled via a probe. The coupling via the slots is defined mathematically as positive coupling. The probe is selectively configurable to provide positive or negative coupling relative to the sign of the slot coupling. Further, at least one non-adjacent, non-sequential pair of cavities is coupled via a second probe that may be configured to provide either positive or negative coupling relative to the sign of the slot coupling. The filter housing supports a plurality of adjustable fins which extend into the slots, one fin to each slot, to selectively adjust the size of the slot.

Abstract: Multi-mode waveguide filters are temperature compensated using dielectric material contained within at least one cavity of a filter. The variation in operating frequency of the filter that would otherwise result from changes in temperature is substantially balanced by a change in operating frequency with temperature caused by a change in a dielectric constant of the dielectric material so that the operating frequency of the filter remains substantially constant with temperature. The filter can have one or more dual-mode or triple-mode cavities. In a method of constructing and compensating a filter, the amount of dielectric material is selected so that the dielectric material does not resonate at the operating frequency of the cavity, the amount of dielectric material in the cavity being adjustable after each cavity is constructed.

Abstract: Microwave bandpass filters contain dielectric resonators mounted in dielectric blocks, which are in turn mounted in cavities. There can be more than one dielectric resonator per cavity. Significant size reduction has been achieved over prior art filters. The filters can be operated at cryogenic temperatures and since the results attainable at cryogenic temperatures are repeatable, the filters can be tuned at cryogenic temperatures and returned to room temperature before being returned to cryogenic temperatures for operating purposes. When operated at cryogenic temperatures, the filters contain shorting plates having high temperature superconducting material thereon. The filters can be constructed with various configurations and can be operated in either a single mode or a dual-mode. Previous single mode or dual-mode dielectric resonator filters are larger in size and mass than the filters of the present application.

Abstract: A radio frequency switch operates by permanent magnets located in a rotatable actuator. The permanent magnets of the actuator are arranged in groups so that there is at least one magnet in each group that has an opposite polarity to another magnet in the same group. The permanent magnets within the same group are located adjacent to one another. Conductors within an RF cavity have permanent magnets mounted thereon where all of the magnets have the same polarity. The switch can be moved from a first position to a second position by moving the actuator a distance not exceeding 40.degree. and, preferably from 10.degree. to 30.degree.. In the first position, one permanent magnet of one group interacts with the magnet on the conductor to move the conductor. In the second position, another magnet of the same group interacts with the magnet of the conductor to move the conductor.