United States of America as Represented by the Administrator of Nasa

The United States of America as Represented by the Administrator of the

The United States of America as Represented by the Administrator

Robert R Romanofsky

Felix Antonio Miranda

Kurt A Shalkhauser

Kul B Bhasin

An apparatus that combines an antenna and telescope to minimize system mass without compromising performance of either the antenna or telescope. The apparatus includes a sub-reflector placed before a prime focus feed of a hybrid reflector system. The apparatus also includes a radio frequency (RF) reflector is rigidly attached to a body of a spacecraft and an optical section is attached to a vibration isolation platform.

Near earth and deep space communications system

A method of manufacturing a cellular reflectarray antenna arranged in an m by n matrix of radiating elements for communication with a satellite includes steps of determining a delay &#x3c6;m,n for each of said m by n matrix of elements of said cellular reflectarray antenna using sub-steps of: determining the longitude and latitude of operation, determining elevation and azimuth angles of the reflectarray with respect to the satellite and converting theta(&#x3b8;) and phi(&#x3c6;), determining &#x394;&#x3b2;, the pointing vector correction, for a given inter-element spacing and wavelength, determining &#x394;&#x3c6;, the spherical wave front correction factor, for a given radius from the central element and/or from measured data from the feed horn; and, determining a delay &#x3c6;m,n for each of said m by n matrix of elements as a function of &#x394;&#x3b2;and &#x394;&#x3c6;.

Cellular reflectarray antenna and method of making same

A method of manufacturing a cellular reflectarray antenna arranged in an m by n matrix of radiating elements for communication with a satellite includes steps of determining a delay &#x3c6;m,n for each of said m by n matrix of elements of said cellular reflectarray antenna using sub-steps of: determining the longitude and latitude of operation, determining elevation and azimuth angles of the reflectarray with respect to the satellite and converting theta(&#x3b8;) and phi(&#x3c6;), determining &#x394;&#x3b2;the pointing vector correction, for a given inter-element spacing and wavelength, determining &#x394;&#x3c6;, the spherical wave front correction factor, for a given radius from the central element and/or from measured data from the feed horn; and, determining a delay &#x3c6;m,n for each of said m by n matrix of elements as a function of &#x394;&#x3b2;and &#x394;&#x3c6;.

A multi-mode broad band patch antenna is provided that allows for the same aperture to be used at independent frequencies such as reception at 19 GHz and transmission at 29 GHz. Furthermore, the multi-mode broadband patch antenna provides a ferroelectric film that allows for tuning capability of the multi-mode broadband patch antenna over a relatively large tuning range. The alternative use of a semiconductor substrate permits reduced control voltages since the semiconductor functions as a counter electrode.

Multi-mode broadband patch antenna

The present invention provides a High Resolution Scanning Reflectarray Antenna (HRSRA) for the purpose of tracking ground terminals and space craft communication applications. The present invention provides an alternative to using gimbaled parabolic dish antennas and direct radiating, phased arrays. When compared to a gimbaled parabolic dish, the HRSRA offers the advantages of vibration free steering without incurring appreciable cost or prime power penalties. In addition, it offers full beam steering at a fraction of the cost of direct radiating arrays and is more efficient.

High resolution scanning reflectarray antenna

A tunable local oscillator (10) with a tunable circuit (12) that includes a resonator (16) and a transistor (14) as an active element for oscillation. Tuning of the circuit (12) is achieved with an externally applied dc bias (22, 24) across coupled lines (20) on the resonator (16). Preferably, the resonator (16) is a high temperature superconductor microstrip ring resonator with integral coupled lines (20) formed over a thin film ferroelectric material. A directional coupler (38) samples the output of the oscillator (14) which is fed into a diplexer (40) for determining whether the oscillator (14) is performing at a desired frequency. The high-pass and low-pass outputs (42, 44) of the diplexer (40) are connected to diodes (48, 46) respectively for inputting the sampled signals into a differential operational amplifier (50). Amplifier (50) compares the sampled signals and emits an output signal if there is a difference between the resonant and crossover frequencies. Based on the sampled signal, a bias supplied to the ring resonator is either increased or decreased for raising or lowering the resonant frequency by decreasing or increasing, respectively, the dielectric constant of the ferroelectric.

Discriminator stabilized superconductor/ferroelectric thin film local

A phase shifter having a reference path and a delay path, light sources, and superconductive switches. Each of the superconductive switches is terminated in a virtual short circuit, which may be a radial stub. Switching between the reference path and delayed path is accomplished by illuminating the superconductive switches connected to the desired path, while not illuminating the superconductive switches connected to the other path.

Monolithic MM-wave phase shifter using optically activated

An MMIC test fixture includes a bias module having spring-loaded contacts which electrically engage pads on a chip carrier disposed in a recess of a base member. RF energy is applied to and passed from the chip carrier by chamfered edges of ridges in the waveguide passages of housings which are removably attached to the base member. 'Thru', 'Delay' and 'Short' calibration standards having dimensions identical to those of the chip carrier assure accuracy and reliability of the test. The MMIC chip fits in an opening in the chip carrier with the boundaries of the MMIC lying on movable reference planes thereby establishing accuracy and flexibility.

Growing community of inventors

Hinckley, OH, United States of America

Robert R Romanofsky