California Institute of Technology

Trw Limited

David B Rutledge

Seyed Ali Hajimiri

Scott D Kee

Ichiro Aoki

James Jordan Rosenberg

Blythe Chadwick Deckman

Michael Peter DeLisio

Chun-Tung Cheung

Aydin Babakhani

Gabriel M Rebiez

The invention is a radio transmitter that includes an antenna having at least one driven element and at least one reflector element. The driven element is electrically coupled to a radio carrier source. At least one of the driven elements or the at least one reflector element, includes at least one switch to modulate the radio carrier. Also, a secure communication system includes a radio transmitter configured to transmit a modulated signal within an information beam width. Also, a method for modulating a radio signal includes the steps of causing the transmitted carrier signal to be modulated by the modulation signal in response to switching the at least one reflector switch. Also, a method for selecting desirable antenna reflector switch combinations includes performing a mathematical simulation to determine whether the combination of reflector switch positions results in a modulated signal that can be demodulated within an information beam width.

Transmitter architecture based on antenna parasitic switching

The present invention discloses a distributed power amplifier topology and device that efficiently and economically enhances the power output of an RF signal to be amplified. The power amplifier comprises a plurality of push-pull amplifiers interconnected in a novel circular geometry that preferably function as a first winding of an active transformer having signal inputs of adjacent amplification devices driven with an input signal of equal magnitude and opposite phase. The topology also discloses the use of a secondary winding that matches the geometry of primary winding and variations thereof that serve to efficiently combine the power of the individual power amplifiers. The novel architecture enables the design of low-cost, fully-integrated, high-power amplifiers in the RF, microwave, and millimeter-wave frequencies.

Distributed circular geometry power amplifier architecture

A system for amplifying a signal is provided. The system includes a wave guide and an active loop amplifier disposed in the wave guide. The active loop amplifier receives the signal and generates a magnetic field in response to the signal, such as one that couples to the propagating mode of the wave guide.

Active-loop, spatially-combined amplifier

The present invention discloses a new family of switching amplifier classes called &ldquo;class E/F amplifiers.&rdquo; These amplifiers are generally characterized by their use of the zero-voltage-switching (ZVS) phase correction technique to eliminate of the loss normally associated with the inherent capacitance of the switching device as utilized in class-E amplifiers, together with a load network for improved voltage and current wave-shaping by presenting class-F impedances at selected overtones and class-E impedances at the remaining overtones. The present invention discloses a several topologies and specific circuit implementations for achieving such performance.

Class E/F switching power amplifiers

The present invention relates to a bias tracking network that manipulates the DC value of the control voltage applied to the active devices in each quasi-optic cell within an array of cells. The purpose of this network is to compensate for variations in the main DC bias supply voltage provided to each cell. In one embodiment, the bias tracking network includes a set of resistive voltage dividers at the boundary of each cell, together with resistors inserted within the conductors that carry a reference voltage from which the control voltage for each cell is derived. This impedance network introduced at each cell boundary causes the control voltage to &ldquo;track&rdquo; the variation in the voltage of the return lead (i.e., the &ldquo;ground lead&rdquo;) at each cell in the array, in order to maintain a consistent (or desired) control voltage distribution to each cell in the array.

Method for controlling bias in an active grid array

The present invention discloses active unit cell topologies for quasi-optic grid array structures that make use of combinations of one of several broadband or frequency-selective positive (or regenerative) feedback networks, as well as multiple transistor configurations in order to enhance the gain of the grid array amplifier. These new topologies yield higher gain, extending the utility of the grid array amplifier to both new applications requiring higher gain, as well as to higher frequencies where the intrinsic gain of the active devices is lower. They also offer greater flexibility in impedance matching, improving the bandwidth and manufacturability of the design.

Techniques for enhancing gain in a quasi-optic grid array

The present invention discloses a simple adapter that transitions between a standard rectangular waveguide environment and the quasi-plane wave (quasi-TEM mode) environment of an active grid array assembly. The device may serve as a mode expanding waveguide feed or as a mode contracting waveguide collector.

Mode translating waveguide adapter for a quasi-optic grid array

The present invention discloses an electronically frequency tunable and phase modulatable quasi-optic grid oscillator. The oscillator includes a reference signal input port whereby a small external reference signal is introduced that entrains the frequency and phase of the oscillator signal to it. Amplitude modulation techniques are introduced to further enhance the utility of the oscillator as a modulator.

Electronically tunable and modulatable quasi-optic grid oscillator

A nonresonant, traveling-wave V-shaped slot antenna providing high gain and a broad bandwidth for coupling infrared radiation onto a detector. The V-shaped slot antenna includes a relatively thick dielectric substrate and a metallization layer formed on the substrate. The metallization layer includes a pair of slots positioned at an angle .phi..sub.1 to form a V-shaped slot. The slot angle .phi..sub.1 is equal to approximately twice the radiation angle .psi., which is defined as the arccos of v.sub.d /v.sub.s, where v.sub.s is the propagation velocity of the infrared radiation in the two slots and v.sub.d is the propagation velocity of the radiation in the dielectric substrate. At the slot angle .phi..sub.1, the radiation in the two slots adds in phase to produce a single high-gain beam along the V axis.

High-gain broadband V-shaped slot antenna

An integrated circuit antenna structure for transmitting or receiving millimeter and/or submillimeter wave radiation having an antenna relatively unimpaired by the antenna mounting arrangment is disclosed herein. The antenna structure of the present invention includes a horn disposed on a substrate for focusing electromagnetic energy with respect to an antenna. The antenna is suspended relative to the horn to receive or transmit the electromagnetic energy focused thereby.

Growing community of inventors

Pasadena, CA, United States of America

David B Rutledge