Abstract: This invention reduces the number of amplifiers needed and thus reduces the weight of a multi-beam transmitting system. Each input beam is connected respectively to each switched terminal of an input switch. The fixed terminal of the input switch is connected to the input of an amplifier the output of which is connected to the fixed terminal of an output switch. Each switched terminal of the output switch is connected respectively to transmit feeds which are located off-set from the prime focus of a transmit reflector antenna. Both the input and the output switches are switched synchronously. The invention includes MMIC and high Tc superconducting transmit systems. The invention includes design to prevent single point failures and a design to transmit a large amount of RF power.

Abstract: A symmetrical coplanar waveguide is formed by a spiral with three arms. One arm is 1, the second arm is 2 and the 3rd arm is 41. The arms 1 and 2, and spiral arms 1 and 41 are separated by equal distance. The spiral arms 1, 2 and 41 are formed by the deposition of films of a conductor, layer 3, on a film 14 of a single crystal ferroelectric material, layer 2, which is deposited on a single crystal dielectric material, layer 1. Input is 10 and the output is 11. The CPW spiral arms 1, 2 and 41 form a time delay device. When a bias voltage V is applied between the spiral arms 1 and 2, and between 1 and 41 through a bias filter made of L and C, the permittivity of the ferroelectric film between the spiral arms 1 and 2, and between 1 and 41 or across the CPW, changes producing a change in the time delay.

Abstract: A coplanar waveguide is formed by a spiral with two arms. One arm is labelled 1, and the second arm is labelled 2. The arms labelled 1 and 2 are separated by equal distance. The spiral arms labelled 1 and 2 are formed by the deposition of a film of a conductor, a third layer, on a film 14 of a single crystal ferroelectric material, a second layer, which is deposited on a single crystal dielectric material, a first layer 1. Input is 10 and the output is 11. The CPW spiral arms labelled 1 and 2 forms a time delay device. When a bias voltage V is applied between the two spiral arms labelled 1 and 2 through a bias filter made of an inductor L and a capacitor C, the permittivity of the ferroelectric film between the two spiral arms labelled 1 and 2, or across the CPW, producing a change in the time delay.

Abstract: A design of equally loaded, under varying traffic load conditions, high efficiency power amplifiers for a multibeam communication system is presented. Output beam contains signals of only one beam corresponding to its input beam. Signals arriving at the feed elements for an input beam "b", of the 1 to N beams, corresponding to an input beam "b", arrive in phase and add together, while signals arriving at said feed elements for the output beam "b" corresponding to the remaining input beams arrive in antiphase and cancel one another by appropriate selection of two set of fixed input and output phase shifters. The output beams are shaped to produce a small reduction of power at the crossover point of adjacent beams. MMIC and high Tc superconducting designs, including the design of high Tc superconducting reflector antenna, are presented.

Abstract: The high power band-pass filters are made of sections of circular waveguide resonators with sections of waveguide in between them. In the center of the waveguide resonator a ferroelectric disc, with a hole in the center, is placed. A bias is applied to the inner side of the ferroelectric disc. On the application of a bias voltage, the permittivity of the ferroelectric disc changes. As a result, the resonant frequency of the circular cavity changes. Application of different levels of bias voltages produces different resonant frequencies of the filter. The interior conducting surfaces of the waveguide(s) and the waveguide resonator(s) have high Tc superconducting material and the waveguide flanges have high Tc superconducting material on the conducting surfaces.The band-stop filters are made of a section of a main waveguide with branch waveguide resonator(s) connected on the broad-wall of the main waveguide with waveguide sections in between the resonators.

Abstract: This invention pertains to monolithic filters of the band-pass or band-reject type which a single crystal ferroelectric material having an electric field dependent permittivity. The filters are comprised of: a first layer of a single crystal dielectric material; a second layer of a single crystal high T.sub.c superconductor material; a third layer of a single crystal ferroelectric material; and a fourth layer of high T.sub.c superconductive microstrip lines configured into the various filter circuits, including resonator circuits and transformer circuits. The filters are capable of operating at power levels up to 0.5 MW at a temperature slightly above the Curie temperature to avoid hysteresis.

Abstract: A coaxial cavity is loaded with a single crystal ferroelectric rod whose permittivity is dependent on the electric field in which it is immersed. Application of a bias voltage changes the permittivity of the ferroelectric rod of the cavity and thus changing the frequency of the coaxial cavity. A tunable coaxial filter is obtained. By placing the cavity in the main transmission line, a bandpass tunable filter is obtained. By placing the cavity in a branch line, a band reject tunable filter is obtained.

Abstract: A main CPW structure is formed by depositing two parallel films of a conductor on a film of a single crystal ferroelectric material. Cavities are formed by placing irises in a main CPW structure. These cavities are tuned to a dominant resonant frequency. By the application of a bias voltage to the main CPW structure with cavities, the permittivity of the film of the ferroelectric material, underneath the CPW structure, is changed. Thus the dominant resonant frequency of the filter is changed. By changing the level of the bias voltages, different dominant resonant frequencies of the filter are obtained. Thus a tunable band pass filter is obtained. With branch cavities on a CPW structure deposited on a ferroelectric film, a tunable band reject filter is obtained.

Abstract: A main symmetrical CPW structure is formed by depositing three parallel films of a conductor on a film of a single crystal ferroelectric material. Cavities are formed by placing irises in a main CPW structure. These cavities are tuned to a dominant resonant frequency. By the application of a bias voltage to the main CPW structure with cavities, the permittivity of the film of the ferroelectric material, underneath the CPW structure, is changed. Thus the dominant resonant frequency of the filter is changed. By changing the level of the bias voltages, different dominant resonant frequencies of the filter are obtained. Thus a tunable band pass filter is obtained. With branch cavities on a CPW structure deposited on a ferroelectric film, a tunable band reject filter is obtained.

Abstract: A design of equally loaded, under varying traffic load conditions, power amplifiers for a multibeam satellite is presented. Each output beam contains signals of only one beam corresponding to its input beam. The output beams are shaped to produce a small reduction of power at the crossover point of adjacent beams. MMIC and high Tc superconducting designs, including the design of high Tc superconducting reflector antenna, are presented.

Abstract: A MMIC high Tc superconducting ferroelectric phase shifter is comprised of as microstrip line on a film of a single crystal ferroelectric material. To operate the phase shifter over a desired bandwidth a quadrature band pass filter, having 1,2,3, . . . coupled lines, is coupled to the phase shifter. The microstrip lines are comprised of a high Tc superconductor such as YBCO, TBCCO.

Abstract: A number of MMIC ferroelectric variable time delay devices are presented. Each embodiment has a microstrip configuration deposited on a ferroelectric film which is deposited on a high Tc superconductor substrate connected to the ground. A bias electric field changes the permittivity of the ferroelectric material. As a result, a variable time delay is obtained.

Abstract: Three embodiments of a tunable ferroelectric transmitting system are included. Each embodiment includes a tunable oscillator and a tunable antenna. Two embodiments include a negative resistance diode, the frequency of oscillation being controlled by a single crystal tunable ferroelectric resonator. The third embodiment uses a transistor. The tunable antenna is made of a single crystal tunable ferroeletric resonator. All conducting depositions are made of films of a high Tc superconducting material.

Abstract: High Tc superconducting limiters are designed to operate at two or more levels of input signals. In one waveguide embodiment, multiple half wavelength branch waveguide lines are connected to a main waveguide line. The half wavelength lines are terminated with tuned circuits of a capacitance, made of a ferroelectric material, and an inductance provided by a waveguide line. In another waveguide embodiment, the branch lines are terminated in tuned cavities each having a ferroelectric material. In a microstrip embodiment, multiple half wavelength branch ferroelectric lines of different impedances are connected to a main line. In a second microstrip line embodiment, tuned circuits, with differing L and C values, are connected to a main transmission line through a half a wavelength branch transmission line. The capacitance is made of a ferroelectric material. The conductor, deposited on the microstrip lines, and the waveguides are made of a single crystal high Tc superconductor.

Abstract: A design of equally loaded, under varying traffic load conditions, power amplifiers for a multibeam satellite is presented. Each output beam contains signals of only one beam corresponding to its input beam. The output beams are shaped to produce a small reduction of power at the crossover point of adjacent beams. MMIC and high Tc superconducting designs, including the design of high Tc superconducting reflector antenna, are presented.

Abstract: The design of a high Tc superconducting band reject tunable ferroelectric filter (TFF) is presented. The band reject TFF consists of a main microstrip line on a dielectric substrate. One or more half wavelength microstrip resonators, on a ferroelectric substrate, is coupled to the main microstrip line. At a resonant frequency of a resonator, a short circuit is presented on the main microstrip line resulting in a rejection of signal of that frequency. By applying a bias voltage to a resonator, the frequency of the resonator and, as such, the reject band of the filter is changed. Different resonators can be tuned to different frequencies.

Abstract: The design of a high Tc superconducting band pass tunable ferroelectric filter (TFF) is presented. The band pass TFF consists of an edge coupled filter on a ferroelectric substrate. Each input and output microstrip line is a quarter wavelength long. Each intermediate microstrip line is a half wavelength long with the first quarter wavelength being coupled to the preceding microstrip line and the remaining quarter wavelength being coupled to the succeeding microstrip line. Each microstrip line is connected, through an LC filter, to a common bias voltage source. Application of a bias voltage changes the frequency of operation of the filter. For matching the impedances of the input and output of the filter to the impedances of an input and output circuit respectively, matching ferroelectric quarter wavelength transformers are provided.

Abstract: A cylindrical cavity is loaded with a ferroelectric rod and is resonant at the dominant mode. The loaded cylidrical cavity is a band pass filter. As a bias voltage is applied across the ferroelectric rod, its permittivity changes resulting in a new resonant frequency for the loaded cylindrical cavity. The ferroelectric rod is operated at a temperature slightly above its Curie temperature. The loaded cylindrical cavity is kept at a constant designed temperature. The cylindrical cavity is made of conductors, a single crystal high Tc superconductor including YBCO and a single crystal dielectric, including sapphire and lanthanum aluminate, the interior conducting surfaces of which are deposited with a film of a single crystal high Tc superconductor. Embodiments also include waveguide single and multiple cavity type tunable filters. Embodiments also include tunable band reject filters.