Abstract: An antenna with first and second spaced radiating elements extending from a vertex at respective first ends and diverging from each other in a direction outward from the vertex to respective second ends. Each radiating element second end is connected to a first end of a terminating element through a coupler. The second end of each terminating element is connected to a common ground plane.

Abstract: An RF transmission system including an RF power amplifier, said system comprising an harmonic cancellation processor. The harmonic cancellation processor produces a predistorted RF input signal to the RF amplifier which cancels harmonic energy generated by the amplifier. The RF output of the amplifier is sampled and stored in the harmonic cancellation processor.

Abstract: The present invention provides a photonic local oscillator signal generator. The generator includes a plurality of waveguides fabricated in a single substrate. The waveguides are fabricated with a lateral separation that enables an evanescent tail of an optical mode field generated in one waveguide to overlap with an evanescent tail of an optical mode field generated in an adjacent waveguide. The overlap of the evanescent tails produce cross-coupling between the laser light generated in the adjacent waveguides. The generator uses a common pumping element to pump laser cavities of both of the waveguides. The use of a common pumping element and the cross-coupling produces phase locking between the laser light generated in the plurality of waveguides. As a result of the phase locking, mutual optical coherence between the laser light is achieved. The mutual optical coherence provides an interference signal upon photodetection.

Abstract: A transmission line antenna assembly having a substantially continuous bandwidth from the microwave region of the electromagnetic spectrum to the VHF region of the spectrum. The antenna assembly includes at least one balanced transmission line antenna element of high-temperature superconductor material supported by a substrate, an antenna cavity supporting the substrate and containing a thermally-conductive electromagnetic-energy-absorbing material therein, and a cryogenic cooler for cooling the antenna element to a temperature at which it exhibits superconductivity.

Abstract: An antenna comprises a dielectric sheet, a pair of conductive feed stems facing one another on opposite sides of the sheet, and a plurality of conductive antenna elements extending away from each feed stem. Each antenna element on one feed stem forms a pair with an antenna element on the other feed stem. In an embodiment, the antenna comprises four pairs of metal feed stems, radiating from a common center. The antenna elements extend alternately to the two sides of each feed stem. Each antenna element forms a dipole with a matching antenna element directly opposite it on the other feed stem of the same pair. Each pair of feed stems and its antenna elements occupies a quadrant of the antenna. The antenna elements do not overlap with other quadrants. Each antenna element zig-zags so that its electrical length is greater than the distance between its ends. Antenna elements on the same side of a pair of stems form zig-zags that are aligned to minimize variations in the spacing between elements.

Abstract: The present invention provides a fiber optic link utilizing asymmetric homodyne modulation and balanced detection to achieve a very high dynamic range. The link uses a Mach Zehnder Modulator to generate a double-sideband suppressed-carrier signal from a laser light signal of a carrier frequency and a modulating signal at a modulating frequency. The laser light signal is phase shifted and injected into the double-sideband suppressed-carrier signal. Two signals are generated wherein the fundamental components are out-of-phase. The two signals are input to a balanced receiver wherein the one signal is subtracted from the other, resulting in the fundamental components adding, thereby providing an improved fundamental signal.

Abstract: A mixing method and mixer structure provide a circuit topology suitable for use in radio receivers, transmitters, tuners, instrumentation systems, telemetry systems, and other systems and devices performing frequency conversion in either homodyne or heterodyne implementations. The inventive mixer may be used for wireless communication devices including radios, cellular telephones, and telemetry systems whether land, sea, airborne, or space based, and whether fixed or mobile. The mixer provides superior intermodulation and harmonic distortion suppression and features excellent conversion loss, noise figure, port match, and port isolation as a result of its circuit topology. The mixer device circuit combines the advantages of series mixing FETs, a triple balanced design using a balanced passive reflection transformer, a precise local oscillator phase splitter, and square wave gate drive having high slew rate signal characteristics to achieve high levels of performance.

Abstract: A radio comprising an FET mixing device for multiplying a first-frequency signal with a second frequency signal to generate a third frequency analog mixer output signal. A local oscillator input port receives a periodic sinusoidal local oscillator signal at a local oscillator frequency from an external local oscillator source. A drive circuit generates a substantially square-wave two-voltage level switching signal for driving said mixing device. An analog-to-digital converter generates a digital representation of said third frequency analog mixer output signal.