Hughes Electronics Corporation

Other

The Boeing Company

Hector J De Los Santos

Andrew H Kwon

Eric D Ditmars

David H Chow

Lap Wai Chow

Joel N Schulman

Yu-Hua Kao Lin

Ronald M Hickling

John R Dunwoody

Arturo L Caigoy

Yu-Hua Kao

A redundant microwave system operable to process a microwave signal propagating in a microwave cavity includes a microwave cavity and two microwave processing devices. Each microwave processing device has a transmissive impedance when it is on and a reflective impedance when it is off. There is a separate coupling probe extending from each of the microwave processing devices to locations within the microwave cavity. When a primary one of the microwave processing devices is switched on and the redundant microwave processing device is switched off, its coupling probe reflects energy so that almost all of the energy flows through the primary microwave processing device. If the primary microwave processing device fails and is switched off, its coupling probe reflects energy so that almost all energy flows through the redundant device. No separate active switching device or circuit is used.

Microwave system with redundant processing devices and passive switching

A microwave microstrip/waveguide transition structure includes a substrate, an elongated microstrip layer residing on a surface of the substrate, and an elongated integral hollow waveguide on the surface of the substrate. The microstrip layer and a side of the hollow waveguide constitute a single continuous piece of metal. The transition structure is fabricated by providing a substrate, depositing a metallic layer on the substrate, and depositing a metallic hollow housing continuous with a portion of a length of the metallic layer. The metallic hollow waveguide bounded by the metallic layer and the metallic hollow housing and having a contained volume therewithin is thereby defined.

Method of fabricating a microwave microstrip/waveguide transition structure

A sample and hold circuit that is coupled to a control voltage source and a signal source has a sampling bridge coupled in series between a first resonant tunneling diode. The bridge comprises a plurality of diodes. The sampling bridge couples an input voltage signal that is to be sampled to a holding capacitor when the sampling bridge is forward biased. The bridge substantially decouples the input voltage signal from the holding capacitor when the sampling bridge diodes are reversed biased. The resonant tunneling diodes when reversed biased allow the bridge to be isolated from the control voltage source to allow the holding capacitor to float at the sampled value of the input voltage.

Sample and hold circuit

A resonator tuning system includes an apparatus coupled to a resonator for changing the resonator's resonance frequency. Tuning of the resonator is accomplished by varying the coupling to a capacitor or varactor, rather than by varying the capacitor. An interferometer, such as a Mach-Zender interferometer is coupled to the resonator and changes the resonance of the resonator by applying an actuation voltage to vary the coupling to the resonator. In this way, a resonator may be tuned and maintain high unloaded Q properties while being coupled to a varactor or other load.

Resonator tuning system

A bistable micro-electromechanical switch (,) having two parallel plate capacitors (,) spaced a distance from each other on a substrate (,). A transmission line (,), having a detached segment (,), that is movable or the substrate (,), is located on the substrate (,) between the parallel plate capacitors (,). A dielectric beam (,) is attached to the movable transmission line segment (,) and the ends of the dielectric beam (,) protrude into each of the parallel plate capacitors (,). When a voltage (,) is applied to one of the capacitors (,or,), the dielectric beam (,) is pulled into the capacitor (,or,) and brings the movable transmission line segment (,) with it. As the transmission line segment (,) is moved either into, or out of, alignment with the transmission line (,), a path through the transmission line is either closed, or opened.

Bistable micro-electromechanical switch

A launch quasi-optical amplifier including a photonic bandgap crystal, designed to operate within a specific frequency range. The photonic bandgap crystal is populated with active devices that are coupled to the alternate layers, or defects, in the crystal to compensate for the absorption in the alternate layers thereby creating a negative absorption coefficient. The photonic bandgap crystal is operable as an amplifier when the active devices are amplifiers, and as a wave source when the active devices are oscillators.

Quasi-optical amplifier

A microelectromechanical (MEM) device includes a substrate and a flexible cantilever beam. The substrate has positioned thereon a first interconnection line separated by a first gap and a second interconnection line separated by a second gap parallel to the first interconnection line. The substrate also has positioned thereon a first and second primary control electrode wherein one of the first and second primary control electrodes is positioned on one side of one of the first and second interconnection lines and the other one is positioned on the other side of the other first and second interconnection lines. The flexible cantilever beam has a top surface and a bottom surface and a beam width slightly larger than the gap widths at the gaps. A flexible anchor is secured to the bottom surface of the beam at a center of the beam and attached to a center of the substrate so as to position the beam orthogonally to the first and second interconnection lines. Secondary control electrodes are secured to the bottom surface of the beam and positioned opposite the primary control electrodes. First and second contact pads are secured to the bottom surface of the beam and positioned opposite the first and second interconnection lines.

Microelectromechanical device

A microelectromechanical switch having a beam cantilevered from a switch base, a first control electrode, having no path to ground, in contact with the fixed end of the cantilevered beam and a second control electrode, also having no path to ground, mounted to the switch base underneath the cantilevered beam, but not in contact therewith. A contact electrode is located underneath the free end of the cantilevered beam. The first and second control electrodes are manipulated to actively effect both the ON and OFF states of the microelectromechanical switch by forcing the beam in and out of contact with the contact electrode.

Single-pole single-throw microelectro mechanical switch with active

A tracking analog-to-digital converter (ADC) which incorporates an input device, such as a superlattice, which produces a pulsating output current corresponding to the voltage level of an analog input voltage and an encoding device to provides a unique digital code which can be read to yield an approximation of the analog input voltage level. By simultaneously tracking the analog input voltage, the device operates at higher speeds than previously attainable. The resolution of the new ADC is increased by composing the input device to respond to narrow voltage ranges. When the input device is a superlattice, narrow response ranges are accomplished by composing the superlattice to have an increased number of resonances or by vertically stacking a plurality of superlattices.

Tracking analog-to-digital converter

Active electronic circuits are immersed in photonic bandgap crystals (PBC's) that form part of transmission lines for propagation of output signals of the electronic circuits. The output signals of the electronic circuits are accompanied by noise signals that result from spontaneous emission in emission frequency bands which are associated with the active electronic circuits. The PBC's are configured to have photonic bandgaps that include at least a portion of the emission frequency bands. Because the active electronic circuits are immersed in the photonic bandgap crystal, the launch of at least a portion of the noise signals into the transmission line is thereby inhibited. Consequently, the output signal and less than all of the noise signals are propagated along the transmission line, i.e., the noise content of the circuit output is reduced.

Noise-reduction systems and methods using photonic bandgap crystals

A BJT, an inductor, and an RTD are configured to define a negative resistance oscillator circuit that is suitable for monolithic integration. The BJT is forward biased so that the RTD operates at a DC operating point (I.sub.Q,V.sub.Q) on its characteristic I-V curve in its negative differential resistance region. The thermal noise inherent in the circuit causes it to start oscillating about the DC operating point (I.sub.Q,V.sub.Q) where the RTD's negative resistance R.sub.n provides positive feedback that amplifies the oscillations until equilibrium is established thereby producing a sinusoidal waveform. The low power BJT/RTD oscillator operates at power levels approximately one-tenth those of known integrated feedback oscillators and oscillates at frequencies in the hundreds of Ghz range that are currently only achievable using waveguide oscillators.

Bipolar junction transistor (BJT)--resonant tunneling diode (RTD)

An active microwave notch filter is formed by connecting a photonic bandgap crystal (PBC) in a feedback loop around a microwave amplifier. The PBC has an attenuation bandgap which establishes a frequency range of preferential amplification. Frequency selectivity can be achieved by applying signals to the dielectric members which form the PBC to vary their dielectric constants, and thus the bandgap, or by selecting among multiple parallel PBCs. Antennas are provided to transduce the electrical input to the PBC into electromagnetic radiation, and then back to an electrical signal after the radiation has been filtered by the PBC.

Microwave active notch filter and operating method with photonic bandgap

A desired frequency response of a microwave network on a monolithic microwave integrated circuit (MMIC), a microwave integrated circuit (MIC), or a hybrid circuit is achieved by selectively switching MEM switches to change the network topology. In a filter network, MEM switches connected between capacitors and inductors are selectively switched to change the network configuration to achieve a desired frequency response. In an amplifier network, the MEM switches are selectively switched to tune the amplifier to a desired frequency response and to reduce harmonic output.

Tunable microwave network using microelectromechanical switches

Frequency multiplexers that incorporate either a power divider network or a power coupling cavity in conjunction with photonic bandgap filters. The frequency multiplexers comprise a signal input and a plurality of signal outputs. In a first embodiment of the multiplexer, a 1-to-N power divider network is coupled to the signal input, and a predetermined number of photonic bandgap filters are coupled between the divider network and the plurality of signal outputs and that are driven by the divider network. Each photonic bandgap filter has an predetermined bandpass characteristic such that the plurality of filters cover the total input signal bandwidth. In a second embodiment of the multiplexer, a cavity is formed between the signal input and the plurality of filters. The spatial locations of the filters tailor the propagation properties of the cavity so that a corresponding plurality of propagating modes are established linking the different input frequency bands and the signal output. Each filter comprises a wave launching antenna, a waveguide-like cavity, a receiving antenna, and a photonic bandgap crystal disposed in the waveguide-like cavity that comprises a dielectric substrate having upper and lower metal boundaries that define lengths of dielectric members therein, and at least one switch interconnecting pairs of dielectric members formed in the substrate.

Growing community of inventors

Inglewood, CA, United States of America

Hector J De Los Santos