The Boeing Company

Kenneth G Voyce

Ming Chen

Robert Tilman Worl

Harold J Redd

Dan R Miller

Isaac Ron Bekker

Fong Shi

Bernard J Lamberty

Paul R Norris

Mark A Curry

Bruce Larry Blaser

Jay H McCandless

Steven J Peters

Kyle A Dallabetta

A dual beam dual-selectable-polarization phased array antenna comprises an aperture unit, a printed wiring board, radiating elements, chip units, a pressure plate, and a rear housing unit. The printed wiring board has sub assemblies bonded to each other with a bonding material providing both mechanical and electrical connection. The printed wiring board is connected to the aperture unit. The radiating elements are formed on the printed wiring board. The chip units are mounted on the printed wiring board. The chip units include circuits capable of controlling radio frequency signals radiated by the radiating elements to form dual beams with independently selectable polarization. The pressure plate is connected to the aperture unit. The aperture unit is connected to the rear housing unit such that the aperture unit covers the rear housing unit.

Dual beam dual selectable polarization antenna

A particular portable radio frequency identification (RFID) reader includes an active antenna array including a plurality of antenna elements to receive RFID signals from RFID devices. The antenna elements include control circuitry to control a beam pattern generated by the active antenna array. The portable RFID reader further includes sum circuitry and difference circuitry. The sum circuitry is operable to determine a sum signal by summing the RFID signals received by at least two of the plurality of antenna elements. The difference circuitry is operable to determine a difference signal between the RFID signals received by at least two of the plurality of antenna elements. The portable RFID reader also includes a controller to electronically steer the beam pattern and to determine a direction from the RFID reader to a particular RFID device.

Portable radio frequency identification (RFID) reader

A system and method for using a phased array antenna to concurrently receive an RF signal transmitted by a remote transmitter, to determine the angular location of the remote transmitter using the transmitted signal, and to use that angular location to direct a transmit antenna to transmit information in the direction of the transmitter is disclosed.

Phased array antenna beam tracking with difference patterns

Various techniques are disclosed to suppress undesired signal components introduced by non-linear amplifiers of phased array antenna systems to accommodate bandwidths greater than one octave. For example, in accordance with one embodiment, a phased array antenna system includes first and second antenna elements adapted to provide first and second received signals in response to a radio signal. The second antenna element is rotated approximately 180 degrees in relation to the first antenna element. Amplifiers may amplify the received signals to provide amplified signals having a bandwidth greater than one octave. Undesired components of the amplified signals introduced by the amplifiers may be suppressed through appropriate phase shifts performed by associated phase shifters and/or power combiners. A power combiner may combine the first and second output signals to provide a combined signal, wherein the first and second undesired components are suppressed in the combined signal relative to the amplified signals.

Phased array antenna system to achieve suppression of undesired signal components

In a Frequency Modulated Continuous Wave (FMCW) radar, a radar return signal is mixed with a delayed frequency sweep waveform to gain a ranging signal to noise ratio (RSNR) higher than the RSNR available from mixing the return signal with a transmitted waveform.

Delayed frequency sweep for FMCW radar

A microwave transceiver using a reflection pumped mixer includes an electromagnetic signal generator, a subreflector, a reflector of electromagnetic signals from the subreflector, a mixer, circulator, and processing circuitry to relate electromagnetic signal frequency differences to the range of a target from the transceiver. Such frequency differences are detected by the mixer from the captured electromagnetic signals reflected distant targets and reflected electromagnetic signals from the subreflector.

Microwave transceiver using a reflection pumped mixer

A circuit for generating an output signal having an output frequency that varies linearly with time, and to an FM CW radar system utilizing such a circuit. The circuit includes a voltage controlled oscillator that produces an output signal at its output terminal at an output frequency that corresponds to the voltage of an input tuning signal. A comparison signal circuit receives the output signal and produces a periodic comparison signal such that when the output frequency varies by .DELTA.f, the comparison signal frequency varies by .DELTA.f/N where N is a positive integer. An update counter periodically causes the value of N to change by a predetermined integer amount. A phase detector compares the comparison signal to a periodic reference signal, and produces a correction signal that is filtered to provide the tuning signal for the VCO. The value of N is preferably changed at an update frequency that is equal to the frequency of the reference signal times an integer. The comparison signal circuit preferably includes a local oscillator for converting the output signal into a periodic IF signal for input to a divider. A high side local oscillator is preferred to minimize loop gain variation with frequency.

Linear frequency sweep synthesizer

A search oscillator (12) is disclosed for use with a closed-loop system (10) to sense when the system is out of lock and enhance the system's pull-in capabilities. The oscillator includes a loop filter (22) and a sensing circuit (24), composed of a positive limit sensor (26) and negative limit sensor (28). When the system is out of lock, the output V.sub.out of the oscillator slews positive or negative in an effort to restore the system to lock. The positive and negative limit sensors monitor the output and reset it when predetermined thresholds are reached, allowing the search or sweep operation to continue until lock is achieved.

Minimum intrusion search oscillator for use in feedback loops

A polarization diversity system (10) including an adaptive polarization combiner (14) is disclosed. The combiner receives input signals V.sub.i1 and V.sub.i2 of arbitrary relative phase and amplitude, produced in response to orthogonally polarized components of an incident electromagnetic field. The combiner includes a hybrid network (18) that performs the combination of the input V.sub.i1 and V.sub.i2 based on phase adjustments initiated by a feedback circuit (20). The feedback circuit includes a limit set and sensing circuit (26) that allows feedback signals V.sub.c1, V.sub.c2, V.sub.c3, and V.sub.c4 to be swept through a range suitable to phase shifters (28, 32, 36, and 38) included in the hybrid network, thus allowing different components to be more easily used in the hybrid network. Further, the combiner is constructed to function properly in the absence of one of the signals input to the combiner. More particularly, a sensing circuit (22) is employed to disable the sweep function in response to the occurrence of conditions representative of the absence of one of the input signals. As a result, the phase modulation that would otherwise have occurred is limited.

Adaptive polarization combiner

A feedback linearization technique for a power amplifier that does not require the availability of the modulation signals. The RF input signal is down converted to a first IF signal. A portion of the amplifier RF output signal is used to form a feedback signal that is down converted to produce a second IF signal that is subtracted from the first IF signal to produce a different signal. The difference signal is filtered and amplified, and then up converted to RF for input to the power amplifier. Use of feedback at IF avoids stability problems inherent in RF feedback techniques.

Amplifier linearization using down/up conversion

A circuit and method for generating an output signal having an output frequency that varies linearly with time, and an FM CW radar system utilizing such a circuit. The circuit includes a VCO, a rate detector, a phase detector, a filter and an integrator. The VCO produces an output signal at its output terminal at an output frequency that corresponds to the voltage of a tuning signal applied to the VCO input terminal. The rate detector receives the output signal and produces a rate signal having a rate frequency that corresponds to the rate of change of the output frequency. The phase detector compares the rate signal to a reference signal having a fixed frequency, and produces a correction signal corresponding to the phase difference between the rate and reference signals. The filter filters the correction signal to produce a first current signal, and the integrator integrates the first current signal to produce the tuning signal. The circuit may also include a current source for producing a constant magnitude second current signal, in which case the integrator integrates the combined first and second current signals to produce the tuning signal.

Apparatus and method for producing linear frequency sweep

A squelch trigger circuit for use in an RF receiver for receiving a modulated carrier signal having a predetermined information band, and producing a squelch trigger signal. The squelch trigger circuit includes a bandpass filter connected to receive the modulated carrier signal and having a passband that includes the information band. The output of the bandpass filter is connected to an AGC circuit that includes a detector for producing a detection signal indicative of the level of the AGC output signal. The detection signal is input to a high pass filter having a corner frequency selected such that the noise signal includes only frequency components higher than one-half of the passband of the bandpass filter, such that the noise signal produced by the high pass filter corresponds to the out of band noise components of the AGC output signal. The noise signal is input to a noise detector for producing a noise level signal, and the noise level signal is compared to a threshold to produce the squelch trigger signal. The threshold may be temperature compensated to model thermal noise in the AGC circuit.

Growing community of inventors

Bellevue, WA, United States of America

Kenneth G Voyce