Keyword: Antennas

Briefs: Physical Sciences

A technique that involves the use of crossed magnetic antennas in a natural waveguide has been proposed for tracking Martian dust storms from a single observing station; that is,...

Briefs: Electronics & Computers

A seven-element microstrip patch antenna is designed to operate with circular polarization and high gain at a frequency of 2.2875 GHz. The antenna was developed in the early 1990s as a...

Briefs: Electronics & Computers

Researchers at Johnson Space Center (JSC) recently demonstrated that the resonant microstrip patch antenna (RMPA), which has been proven in commercial applications, can be applied with...

Briefs: Electronics & Computers

The upper part of Figure 1 illustrates an antenna derived by widening the middle strip conductor of a finite-width coplanar waveguide (FCPW) to form a rectangular patch. An FCPW offers all the...

Briefs: Information Technology

An algorithm that processes bursts of data generated by scan-mode synthetic-aperture radar (scanSAR) offers some advantages over older scanSAR algorithms. With relatively high computational...

Briefs: Electronics & Computers

Most current radar scanning antennas utilize mechanical scanning, relying on a gimbal, motor, and gear arrangements to physically rotate/elevate the antenna. This technique is slow, gravity-sensitive,...

Briefs: Electronics & Computers

Modules of electronic circuitry that perform the amplitude- and phase-control and the status-monitoring functions for eight-element (2 ×4) subarrays of K-band phased-array antennas...

Briefs: Electronics & Computers

The term "inverse rectenna" may seem like an oxymoron at first glance. However, preliminary experiments have demonstrated that a rectenna of suitable design can be made to operate in...

Briefs: Materials

A portable, self-contained, compact instrument measures and records transient electric fields generated by nearby lightning strikes. This instrument complements, and in many respects...

Briefs: Electronics & Computers
Estimating Attitude From GPS Measurements on One Antenna

A technique for estimating the boresight direction of a Global Positioning System (GPS) receiver antenna involves utilization of the relationship between the strengths of received signals and the direction-dependent antenna gain pattern. The technique is fundamentally different from, and...

Briefs: Physical Sciences
Carbon/Carbon Shield/Antenna Structure

A proposed lightweight, off-axis reflector structure for a microwave communication antenna would be made of a carbon/carbon composite material. The structure was conceived for use aboard the Solar Probe spacecraft, where it would also serve as a shield to protect the spacecraft against solar radiation at...

Briefs: Electronics & Computers
Overview of Tapered-Slot Antennas

A document presents a comprehensive overview of the technology of tapered-slot antennas and arrays of such antennas. The fundamental operation of tapered-slot antennas is not yet fully understood, and, for lack of established design rules, the designs of these antennas have been based primarily on empirical...

Briefs: Electronics & Computers
Control System for Steerable, Rooftop-Mounted Antenna

An excerpt from JPL Document D-12104 presents additional information on the control system of a steerable microwave antenna that is mounted on the roof of a land vehicle and used to communicate with a geostationary satellite. The antenna and control system were described previously in...

Briefs: Electronics & Computers

A computational study has been performed to show that one can accurately compute the cold-test electromagnetic characteristics of the helical slow-wave circuit of a...

Briefs: Electronics & Computers

During the development and testing of signal processing systems, it is useful to generate test signals in the laboratory in order to quantify system parameters such as dynamic range,...

Briefs: Electronics & Computers

The figure illustrates a lightweight composite-material dual-beam reflector antenna for the SeaWinds spaceborne scatterometer instrument, which operates in the Ku band and is designed to...

Briefs: Electronics & Computers

Three coplanar-stripline circuits have been designed to perform coupling and filtering functions in microwave systems. These circuits could be incorporated into feed networks for microwave...

Briefs: Electronics & Computers
Signaling-and-Detection Scheme for Beacon Monitoring

A signaling-and-detection scheme has been proposed for use in conjunction with the remote-monitoring concept described in "Beacon Monitoring Would Reduce Interactions With Remote Systems" (NPO-19706), NASA Tech Briefs, Vol. 21, No. 5 (May 1997), page 54. To recapitulate: A remote system (a...

Briefs: Electronics & Computers

Microbridges that constitute the superconducting-transition sensory elements of electron-diffusion-cooled hot-electron bolometers can now be fabricated in increased yield and...