Abstract: Multiple sensor signals are used to modulate an equal number of frequency-spaced carrier signals in a directional parametric upconverting amplifier. Basically, the carrier signals are separated in a cascaded or parallel configuration of narrow frequency passbands, which also modulate the carrier signals with low-frequency sensor signals. The modulated carrier signals are multiplexed and output over a single signal path, thereby reducing power dissipation. Preferably implemented in superconducting circuitry, the multiplexed amplifier facilitates multiplexing of as many as hundreds of sensor signals and achieves both amplification and upconverting with minimal dissipation of power.

Abstract: A receiver (10) for a wireless telecommunications system that provides relatively wideband signal processing of received signals without increased signal distortion so that multiple received signals can be simultaneously processed. The receiver (10) includes a specialized LNA (16), frequency down-converter (18) and ADC (20) to perform the wideband signal processing while maintaining receiver performance. The frequency down-converter (18) employs a suitable mixer (28), BPA (32), attenuator (34), and transformer (36) that are tuned to provide the desired frequency down-conversion and amplitude control over the desired wideband. The down-converter devices are selected depending on the particular performance criteria of the ADC (20). A specialized digital channelizer (22) is included in the receiver (10) that receives the digital signal from the ADC (20), and separates the signals into the multiple channels.

Abstract: A low noise amplifier topology includes a dual gate transistor device, such as a HEMT device and employs resistive feedback with a DC block associated with the amplifier output to a desired high voltage gain and a low noise figure over a desired range of frequencies.

Abstract: A low noise amplifier topology includes a dual gate transistor device, such as a HEMT device and employs resistive feedback with a DC block associated with the amplifier output to provide a desired high voltage gain and a low noise figure over a desired range of frequencies.

Abstract: A voice-activated microphone and transceiver system includes an interrogator unit for transmitting a signal, receiving a modulated signal, and demodulating the modulated signal such that the difference between the transmitted signal and the modulated signal correspond to a unique sound wave signal. An acoustically driven microphone unit is also included for receiving the signal from the interrogator unit, modulating the signal with the sound wave signal, wherein the sound wave signal contains instructions for controlling an electronic device, and transmitting the modulated signal back to the interrogator unit for analysis by a signal processor.

Abstract: A receiver (10) for a wireless telecommunications system that provides relatively wideband signal processing of received signals without increased signal distortion so that multiple received signals can be simultaneously processed. The receiver (10) includes a specialized LNA (16), frequency down-converter (18) and ADC (20) to perform the wideband signal processing while maintaining receiver performance. The frequency down-converter (18) employs a suitable mixer (28), BPA (32), attenuator (34), and transformer (36) that are tuned to provide the desired frequency down-conversion and amplitude control over the desired wideband. The down-converter devices are selected depending on the particular performance criteria of the ADC (20). A specialized digital channelizer (22) is included in the receiver (10) that receives the digital signal from the ADC (20), and separates the signals into the multiple channels.

Abstract: An image reject sub-harmonic mixer that employs less components than known image reject mixers. The mixer includes a 90° RF coupler, two high pass filters, two anti-parallel diode pairs, two low pass filters and a 90° IF coupler. RF and LO signals are applied to isolated input ports of the 90° coupler. In-phase and quadrature-phase copies of the RF and LO signals are provided at output ports of the coupler. The diode pairs mix the RF and LO signals to generate first and second intermediate frequency signals that are separated in-phase. The high pass filters reject the IF signals to prevent IF power from coupling to the RF and LO ports of the coupler. The low pass filters pass the IF signal and reject the LO and RF signals. Image rejection is obtained by combining the IF outputs of the two diode pair in the 90° IF hybrid.

Abstract: A receiver (10) for a wireless telecommunications system that provides relatively wideband signal processing of received signals without increased signal distortion so that multiple received signals can be simultaneously processed. The receiver (10) includes a specialized LNA (16), frequency down-converter (18) and ADC (20) to perform the wideband signal processing while maintaining receiver performance. The frequency down-converter (18) employs a suitable mixer (28), BPA (32), attenuator (34), and transformer (36) that are tuned to provide the desired frequency down-conversion and amplitude control over the desired wideband. The down-converter devices are selected depending on the particular performance criteria of the ADC (20). A specialized digital channelizer (22) is included in the receiver (10) that receives the digital signal from the ADC (20), and separates the signals into the multiple channels.

Abstract: A low noise amplifier (82) for use in a wireless telecommunications system. The amplifier (82) includes an amplifying device (90), such as an FET, and a plurality of oscillation stabilization components monolithically integrated on a common substrate (132). The stabilization components reduce the gain of the amplifying device (90) at high frequencies to prevent high frequency oscillations. The substrate (132) is on the order of 4 mils thick, so that the operation of the stabilization components are predictable at high frequencies.

Abstract: A packaged electronic system is formed of a base having a surface and a plurality of discrete electronic components disposed on the base surface. An absorbing cover reduces the electromagnetic resonance produced by the discrete electronic components disposed within the packaged system. The entire cover is molded using a composite electromagnetic wave-absorbing plastic material. The cover is selectively plated to satisfy the shielding requirements of the packaged system.

Abstract: An apparatus (800) and method (1000) for forming a shapeable and directable composite beam (305) from a plurality of pixel beams (302). The apparatus (800) includes a front-end unit (810) which communicates element signals through antenna array elements (808). The apparatus (800) also includes a back-end unit (850) which forms the composite beam from a set of pixel beams by converting between a composite signal and a set of corresponding pixel signals. The back-end unit (850) further adjusts the amplitude and phase of the set of pixel signals to form the composite beam. The apparatus (800) further includes an interconnecting beamforming network (820) interposed between the back-end unit (850) and the front-end unit (810) which couples the back-end unit (850) to the front-end unit (810) by converting between the pixel signals of the back-end unit (850) and the element signals of the front-end unit (810). The method (1100) includes determining a desired shape and direction for the composite beam (1110).

Abstract: An RF cable contains an coaxial inner conductor and a coaxial outer shield surrounding the inner conductor in a concentric arrangement. Quarter-wave series sections in the inner conductor and the outer shield severs a direct thermal path along the RF cable, providing low thermal loading for a cryogenic-to-ambient temperature interconnection. The resonant structure of the RF cable permits propagation alternating current and blocks direct current. A method of forming the RF cable comprises depositing metal on a substrate composed of a polymer film having very low thermal conductivity, and winding the metallized substrate into a tubular configuration. The inner conductor may extend laterally beyond the outer shield to provide points of electrical contact.

Abstract: A quenchable VCO that is adapted to be used in switched band synthesizer applications. The VCO may be formed from a heterojunction bipolar transistor (HBT) in a common collector configuration. A quenching circuit which includes a p-i-n diode, is electrically coupled in series with the collector of the HBT. The p-i-n diode is adapted to be monolithically integrated with the HBT. Since the p-i-n diode is electrically connected to the collector of the HBT, as opposed to the base and emitter terminals of the HBT, which forms the main oscillator feedback loop, the Q-factor of the p-i-n diode will have relatively less loading on the phase noise of the HBT oscillator. Moreover, since the p-i-n diode is isolated from the base-emitter junction, the configuration will result in reduced frequency pulling and generation of spurious oscillation and transient effects due to the switching of the p-i-n diode quenched circuit.

Abstract: A direct detection receiver for a passive microwave and millimeter wave radiometric imaging system. The receiver includes a balanced switch low-noise amplifier (BSLNA). A front-end, low-noise amplifier (LNA) is inserted before the BSLNA to achieve a low-noise figure, as well as provide sufficient gain to minimize the input noise figure degradation due to loss of the BSLNA. A high-electron mobility transistor (HEMT) diode is used as a power detector. The front-end amplifier, BSLNA and diode are process compatible for monolithic integration.

Abstract: A hermetic RF pin grid array package methodology is described that obviates the need for glass to metal feedthroughs, simplifying construction, improving reliability and reducing the cost of RF multi-chip modules. An array of cylindrical passages (13, 15) through the module's base plate (3) are aligned with and receive respective associated conductor pins (7, 9) depending from the module substrate (1). Cylindrical metal shrouds (11) are positioned within some passages (15) combine with associated pins (9) to define coaxial RF transmission lines and support for an external RF coax coupling. Unshrouded pins (7) serve to connect DC to the integrated circuit chips in the module. Waveguide interfaces, if required, are provided by conductive coupling structures patterned on the substrate, suspended over a waveguide (17) formed in or about the baseplate.

Abstract: A phased array antenna system producing multiple beams that can be rapidly and reliably scanned between desired angular beam locations without the need for highly complex hardware. The antenna system includes multiple antenna elements (30) coupled to frequency converters (34) that downconvert received signals to an intermediate frequency. Each frequency converter (34) receives a local oscillator (36) signal that passes through a phase shifting circuit (40). The phase shifting circuits are adjusted only in a calibration mode, to remove any phase errors, but are not used to select beam locations. In a receive mode, the downconverted received signals are input to a matrix network (44), such as a Butler Matrix, which transforms the antenna signals on its input lines (42) to an equivalent set of beam location signals on its outputs (46), of which there is one for each possible angular beam location of the antenna system.

Abstract: A durable, broad-band low insertion loss RF feedthrough is formed of a straight conductor (5) centrally supported by, hermetically sealed to and axially extending through the center of a strong, rigid, impervious ceramic disk (3). The ceramic disk is hermetically sealed, directly or indirectly, to the metal barrier (11) through which the feedthrough is to propagate RF energy. The new ferrule and ferrule-less ceramic metal RF feedthroughs avoid the use of glass, conventional in existing feedthroughs. The novel feedthrough serves as the principal element of a microwave microstrip line to waveguide transition.

Abstract: A direct detection receiver for a passive microwave and millimeter wave radiometric imaging system. The receiver includes a balanced switch low-noise amplifier (BSLNA). A front-end, low-noise amplifier (LNA) is inserted before the BSLNA to achieve a low-noise figure, as well as provide sufficient gain to minimize the input noise figure degradation due to loss of the BSLNA. A high-electron mobility transistor (HEMT) diode is used as a power detector. The front-end amplifier, BSLNA and diode are process compatible for monolithic integration.

Abstract: A multi-function, balanced phase shifter and switch having a particular application as a balanced switched low-noise amplifier. The switch includes a hybrid input coupler that couples a first input signal at a first input port and a second input signal at a second input port into a first path and a second path of the switch. Each of the first path and the second path include at least one amplifier and a phase shifter. The phase shifters include a hybrid coupler and two switching devices that are simultaneously switched on or off by a single control signal. Output from the two paths are applied to an output hybrid coupler that couples the output from the two paths into first and second output ports of the switch. By controlling the two control signals applied to the phase shifters to selectively switch the switching devices on and off, signals at the input ports can be selectively amplified and switched to the output ports in a balanced, low-noise manner.

Abstract: An active load applied to the gate transmission line termination of distributed power devices reduces the low frequency noise power appearing at the output of the device. The active load, including at least one active device such as a field effect transistor, operates by transforming the input impedance of a low noise amplifier to the desired load impedance. The active load is connected to one end of an input transmission line having a plurality of impedances connected in electrical series. An input terminal is connected to the opposite end. An output transmission line, also having a plurality of impedances connected in series, has an output terminal at one end and a terminating output impedance at the other. A plurality of active devices are connected to junction points between the series connected impedances of the input and output lines.