Abstract: A high bandwidth operational amplifier architecture has three control loops, which are combined via a voltage-follower-configured field effect transistor. The first control loop is an instantaneous main amplification path and employs positive feedback-based Vgs correction of the output transistor. The second control loop has a bandwidth considerably lower than the first loop and employs negative feedback to correct for long term drift errors. The third control loop, utilizing negative feedback, is a fast path having a bandwidth that overlaps the bandwidth of the first control loop, and corrects for overshoot and undershoot in the main amplification path.

Abstract: A FET or BJT structure or distributed transistor amplifier having a tapered gate feed line and a tapered channel width (tapered source fingers, tapered drain fingers) provides increased bandwidth and gain in the microwave/mm-wave frequency spectrum.

Abstract: A wideband distributed or feedback amplifier monolithic microwave integrated circuit (MMIC) is disclosed that contains an integrated group delay equalizer circuit to compensate for the group delay variation of the amplifier circuitry. The MMIC amplifier is capable of achieving a predicted constant group delay with little variation over a wide frequency range. In addition, the group delay equalizer circuit enables the amplifier to achieve flat (constant) gain over a wide bandwidth, while maintaining constant group delay. Furthermore, the group delay equalizer circuitry requires only a small portion of the total MMIC area.

Abstract: A high frequency filter design for the GHz frequency range is provided. The high frequency filter comprises at least a microstrip design that incorporates both transverse and lateral couplings between the filters resonators. The high frequency filter further incorporates an opened or fully enclosed enclosure over the strip line or microstrip circuitry and may be manufactured on a relatively thick dielectric substrate having a thickness that is greater than about a twentieth of the filter's band-pass wavelength in the dielectric substrate. The high frequency filter design provides a small, easily reproducible filter design better than prior art microstrip filters.

Abstract: Wireless communication methods and systems using multiple sectored cells. In one example, each cell of a cellular coverage area is divided into a number of sectors. A number of different half duplex or full duplex channels are used in each cell to communicate between a base station and a number of subscriber stations located in the cell. At least some of the channels may be reused in other cells of the coverage area. Additionally, some channels may be reused both amongst sectors of a given cell and in other cells of the coverage area. The sectored cells are arranged with respect to one other such that interference amongst similarly oriented sectors of different cells using one or more same channels is reduced.

Abstract: A method and apparatus for utilizing the distortion generated within a portion of a balanced amplifier to cancel the distortion generated within the whole balanced amplifier. Samples of the signal and distortion from part of the balanced amplifier are combined with a reference signal such that the two signals destructively combine leaving the distortion from the sampled part of the balanced amplifier. The gain and phase of the distortion is then adjusted so that when it is coupled into the input of the other part of the balanced amplifier the distortion generated by both parts of the balanced amplifier are cancelled.

Abstract: A duty-cycle adjustable clock generator is disclosed. Combining a fundamental sinusoidal waveform with its phase-locked second harmonic waveform generates the duty-cycle adjustable clock waveform. The clock generator maintains zero DC level and minimum reverse bias voltage swing at high microwave and millimeter wave frequencies. Proper phase shift between the fundamental and second harmonic waveforms produces the desired clock waveform. The duty-cycle is controlled by the magnitude ratio of the fundamental and phase-locked second harmonic waveforms. Due to the resulting zero DC level and minimum reverse bias voltage over the duty-cycle adjustable range, the duty-cycle adjustable clock generator can be effectively used in various microwave and optical communication systems.

Abstract: A printed circuit architecture includes a relatively thick, stiffening base of thermally and electrically conductive material, and a laminate of conductive layers including a printed circuit structure, interleaved with dielectric layers, disposed atop the base. The patterned conductive layers contain an integrated circuit structure that is configured to provide RF signaling, microstrip shielding, and digital and analog control signal leads, and DC power. Low inductance electrical connectivity among the conductive layers and also between conductive layers and the base is provided by a plurality of conductive bores. Selected bores are counter-drilled at the RF signaling layer and filled with insulating plugs, which prevent shorting of the RF signal trace layer to ground, during solder reflow connection of leads of circuit components to the RF signaling layer.

Abstract: A small aspect ratio, high power MMIC amplifier is disclosed. The small aspect ratio MMIC amplifier is capable of achieving the same power levels as conventional power amplifier designs, but with an aspect ratio of near 1:1, versus 4:1 of conventional power amplifiers. The small aspect ratio MMIC amplifier layout uses two different types of FETs, with all gate fingers of both types of FETs running in the same direction. One type of FET is a conventional FET, in which the gate stripes run parallel to the direction of the output. In the conventional FET, the gate manifold and the drain manifold both generally extend in the x-direction (parallel to each other). The other type of FET has gate fingers that run perpendicular to the direction of the output. In this other type of FET, the gate manifold generally extends in the x-direction, while the drain manifold generally extends in the y-direction (perpendicular to each other).

Abstract: A feedforward amplifier is linearized by adapting off the detection of an applied modulation source. The feedforward amplifier has two loops: a first loop and a second loop. Modulators in the two loops are adjusted by controllers that adapt in response to detection of the modulation source injected into the first loop.

Abstract: A computer control device which provides spacial information to a computer or electronic game by sensing the linear acceleration or tilt angle of the control device. The computer control device includes an accelerometer having an enclosure containing a fluid and temperature sensing elements positioned within the enclosure. The fluid moves across the temperature sensing elements in free convection during acceleration or inclination of the enclosure causing a temperature differential between the temperature sensing elements which is measurable. The control device incorporating one or more of these accelerometers senses acceleration or tilt in one to three dimensions and may be used to control a cursor on a computer screen, a display of a virtual reality device, or other computer and electronic game displays.

Abstract: The vehicle control system incorporates an accelerometer which is particularly adapted for use in vehicles due to its readily compensated temperature sensitivity and stable zero g bias. The accelerometer for use in the vehicle control system includes a hermetically sealed enclosure containing a fluid and two temperature sensing elements positioned within the enclosure. When the fluid within the enclosure is heated the convective flow pattern within the enclosure is affected by acceleration of inclination of the enclosure. This change in the convective flow pattern is measured by measuring a temperature difference between the temperature sensing elements to determine the acceleration of the enclosure.

Abstract: A convective accelerometer and inclinometer includes two temperature sensing elements mounted within a sealed enclosure containing a gas. The application of heat to the gas within the enclosure by a heating element causes the gas to flow in a predetermined pattern in free convection. When linear acceleration or inclination is applied to the enclosure the convective flow of gas is affected causing a temperature differential between the temperature sensing elements. This temperature differential is measured as a difference in electrical resistance between the two temperature sensing elements which is proportional to the acceleration. The device can be used to measure linear acceleration, velocity, position or inclination. The device can also be used as an inclinometer for measuring the angle of gravity. The device has a wide variety applications particularly within the automotive field.