The Aerospace Corporation

Samuel S Osofsky

Albert M Young

David A Ksienski

Keven S MacGowan

Allyson D Yarbrough

Robert C Cole

Ruby E Robertson

James P McKay

Gwendolyn M Shaw

Paul E Hanson

Thomas T Tam

A method for reducing intermodulation beams includes applying a beam-smearing phase distribution in addition to a beam-steering distribution for scanning to an array of antenna elements such that multiple higher-order intermodulation products are simultaneously reduced.

Higher-order intermodulation reduction using phase and angle smearing

An intermodulation product reduction or cancellation amplifier received two input signals that are split in quadrature wherein the inphase outputs are summed and then amplified as an inphase signal, and the quadrature outputs are fixed-phase phase-shifted, then summed and then amplified as a quadrature signal. The inphase and quadrature signals are fed into an output hybrid for canceling intermodulation products, where the fixed-phase phase shift is +/&#x2212;60&#xb0; for reducing 3rd order, +/&#x2212;36&#xb0; for reducing 5th order, and +/&#x2212;25.71&#xb0; for reducing 7th order intermodulation products, for examples, for improved signal communications of the two signals over a common antenna or link.

Multiple signal intermodulation reduction system

The hybrid active combiner and circulators serves as a coupler and is a three port network that integrates a directional coupler topology with active devices placed in the coupling paths in order to synthesize a low-loss active combiner circuit or a circulator device with minimal insertion losses. The coupler can have multiple stage amplifiers with transconductance values set according the Pascal's triangle for improved performance, and can function as a low cost and low weight transceiver well suited for various communications systems.

Hybrid active combiner and circulator

The design and performance of an analog cancellation system is presented. The system generates either narrow or wideband nulls in order to minimize the effect of interfering signals on a receiver. A microcontroller directs the detection and classification of the interfering signal relative to frequency, amplitude and modulation, such as pulse-width or continuous wave modulation. A sampled version of the interfering signal at frequency, fi, is phase-inverted, amplified, and vector-summed with the input signal stream to null the interfering signal at fi. The microcontroller also monitors and adjusts the cancellation systems' circuit parameters to minimize any residual interfering signal at fi or respond to changes in the interference. The example system operates from 100-160 MHz, and can generate wideband nulls over a 5MHz bandwidth with a 15dB depth attenuation or narrowband nulls with a Q greater than 200, and with a null depth greater than 30dB.

Adaptive interference cancellation method

A pulse measurement method is applied to test devices such as high power FET transistors for measuring DC device parameters as well as for measuring S parameters during AC testing. The method uses an input gate bias tee for applying an accurately shaped pulsed input, a sensing bias tee for sensing terminal voltages, such as drain voltages for an FET, and a drive bias tee for coupling in a feedback signal provided by an active feedback circuit receiving AC coupled input error signal of the DC terminal voltage and for providing a drive signal as an error signal so as to maintain the applied DC test voltages at stable levels for improved accuracy.

Active feedback pulsed measurement method

A feed-forward linearization of a traveling wave tube amplifier linearizes the transfer function of the tube through a linearization voltage derived at baseband from the instantaneous amplitude of the input signal to control the cathode voltage causing induced phase modulation to offset the normal amplitude modulation to phase modulation conversion distortion. The feed forward linearization control results in reduced distortion for improved phase linearization of the tube over the operating range of the tube.

Feed forward linearized traveling wave tube

A method of manufacturing a micromachined reflector antenna onto a substrate firstly etches a reflector aperture surface defining a dish cavity in an oxide layer and secondly rotates a hinge over the reflector aperture surface with the hinge being used as the reflector central feed. The micromachined reflector can be made into an array of reflector antennas and integrated onto a single substrate with front end receiver circuits operating as a high frequency receiver on a chip reduced in size and cost and operating at hundreds of GHz.

Micromachined reflector antenna method

A micromachined reflector antenna system is integrated onto a substrate by firstly etching a reflector aperture surface defining a dish cavity in an oxide layer and secondly rotating a hinge over the reflector aperture surface with the hinge being used as the reflector central feed. The micromachined reflector antenna system can be made with an array of reflector antennas and integrated onto a single substrate with front end receiver circuits operating as a high frequency receiver on a chip with reduced size and cost and operating at hundreds of GHz.

Growing community of inventors

Rancho Palos Verdes, CA, United States of America

Samuel S Osofsky