Raytheon Company

John Cangeme

Matthew A Morton

Harry B Marr

John Paul Gianvittorio

David V Manoogian

Zhaoyang Charles Wang

Tina P Srivastava

Jack W Holloway

Jeffrey Caldwell

Ajay Subramanian

Samuel E Parker

Gerald M Pitstick

A finite impulse response (FIR) filter including an input of the FIR filter that receives an RF input signal, a clock input configured to receive a clock signal, an output of the FIR filter that provides a filtered output signal, a plurality of signal paths including a plurality of sample-and-hold circuits and a plurality of multipliers arranged in parallel, each signal path including a respective sample-and-hold circuit and a respective multiplier being configured to receive the RF input signal and the clock signal to provide a modulated output signal, an adder configured to receive n modulated output signals from the plurality of signal paths and combine the n modulated output signals to produce the filtered output signal, and a controller.

Reconfigurable gallium nitride (GaN) rotating coefficients FIR filter for co-site interference mitigation

Method and apparatus for leakage signal cancellation in a simultaneous transmit and receive RF system includes: generating a digital transmit signal for transmission from the system; receiving a receive signal produced by reflection of the transmit signal from an object or generated by a second RF system; adaptively filtering the transmit signal by an adaptive finite input response (FIR) filter; calculating filter coefficients for the adaptive FIR filter in real-time at a different sampling rate; adaptively inputting the calculated filter coefficients to the adaptive FIR filter to generate a cancellation signal in real-time; and applying the cancellation signal to the receive signal to cancel leakage in the receive signal to generate an optimum receive signal.

System and method for adaptive simultaneous transmit and receive leakage cancellation

A transmit drive circuit with high signal to noise and frequency agility. In one embodiment, a transmit circuit includes a digital to analog converter, an amplifier, and a signal to noise enhancer, the signal to noise enhancer being a nonlinear passive device that attenuates low-power signals while transmitting high power signals with little loss. The signal to noise enhancer may be fabricated as a thin film of yttrium iron garnet (YIG) epitaxially grown on a gadolinium gallium garnet (GGG) substrate, the GGG substrate secured to a microwave transmission line from the input to the output of the signal to noise enhancer, such that the thin film of yttrium iron garnet is close to the transmission line.

Transmit noise reducer

A method and apparatus for generating accurate estimates of a radar target's azimuth and elevation angles for a phased-phased array rotating radar. Scan modulated coherently integrated (SMCI) monopulse curves are generated from a measured one-way transmit antenna pattern and three receive antenna patterns. The SMCI monopulse curves are calculated in advance for the expected beam steers. To utilize the SMCI monopulse curves, two-way Sum, Delta-Azimuth and Delta-Elevation target returns are coherently integrated, the target's monopulse ratios calculated, and the SMCI monopulse curves or polynomials used to calculate the target's U-offset and V-offset sine-space angles, which are added to the radar's beam steer to get an improved estimate of the target's sine-space angular position denoted as Uand V. A coordinate system transformation transforms Uand Vto azimuth and elevation angles in a non-rotating coordinate system.

Method of generating accurate estimates of azimuth and elevation angles of a target for a phased&#x2014;phased array rotating radar

Growing community of inventors

Hollis, NH, United States of America

John Cangeme