Raytheon Company

E-systems, Inc.

William E Coleman, Jr

Fonzie K Sanders

Christopher T Yates, Ii

Bror Peterson

Mark A Harris

Earnest A Franke

William H Mosley, Jr

Ray B Jones

Mark A Gloudemans

Eugene M Littlefield

Jayanti Patel

Joseph M DeLeon

Reducing the peak-to-average power ratio of a signal comprises receiving the input signal, where the input signal is associated with at least one unacceptable frequency range. The input signal is clipped about an amplitude range to yield a clipped signal and clipped information, where the clipped information represents intermodulation products. The clipped information is filtered to yield an error signal. The error signal represents a subset of the intermodulation products, where an intermodulation product of the subset corresponds to the unacceptable frequency range. The error signal is subtracted from the input signal to yield an output signal.

Reducing the peak-to-average power ratio of a signal

A differential mode inductor includes a first inductor lead that receives a current. A first arm receives the current from the first inductor lead. A center tap receives the current from the first arm. A second arm receives the current from the center tap. The second arm is substantially parallel to the first arm. The current in the first arm flows in the same direction as the current in the second arm. A second inductor receives the current from the second arm.

Differential mode inductor with a center tap

A mutual coupling neutralizer for neutralizing adverse mutual coupling between a pair of patch antennas for mobile communication system. The coupling neutralizer includes a first and second capacitor each having a first end and a second end, where the first ends are coupled to a respective patch antenna. The neutralizer further includes a high impedance transmission line connected to the second ends of the capacitors. The transmission line and capacitors are sized and configured to neutralize adverse mutual coupling between the pair of patch antennas over a predetermined frequency band. The neutralization of mutual coupling is achieved by extracting a signal present at one patch antenna and injecting the signal at the other patch antenna at a substantially equal amplitude and opposite in phase.

Antenna mutual coupling neutralizer

A stripline directional coupler having a quarter-wave transmission line added either between the isolation port of the coupler and the termination impedance or between the input port of the coupler and the signal input reduces the degradation of coupler directivity caused by impedance mismatch of the transmission lines with the source, load and/or termination impedances. With the transmission lines and additional quarter-wave transmission line formed on the same substrate material, coupler directivity is insensitive to the value of the characteristic impedance of the transmission lines. This allows the use of less expensive substrate materials and manufacturing processes during stripline directional coupler construction.

Stripline directional coupler tolerant of substrate variations

A high power RF resistor for use, for example, as an isolation resistor in an RF hybrid splitter/combiner is formed on a thermally conductive substrate. A first insulating beryllia (BeO) layer extends over the substrate and has a top surface and a bottom surface. A first metallization layer extends over the top surface of the first insulating layer and includes a longitudinally-extending gap. A second insulating BeO layer is positioned above the first insulating layer and includes a top surface, a bottom surface and first and second side surfaces. A second metallization layer surrounds the bottom surface and the first and second side surfaces of the second insulating layer and has a longitudinally-extending gap, the gap in the second metallization layer positioned to be in alignment with the gap in the first metallization layer. This structure forms a Faraday shield between the resistive layer and ground to thereby reduce the I.sup.2 R loss resulting from stray capacitance normally associated with isolation resistors. A thin film resistive layer extends over the second insulating layer to form the active resistor element. Preferably, inductors are connected between the terminals of the resistor and ground to tune out parasitic capacitance generated by the metallization layers.

Growing community of inventors

Clearwater, FL, United States of America

William E Coleman, Jr