Ka-Band Solid-State Power Amplifier Module

A compact K_a-band power amplifier has been built with GaAs field-effect transistors (FETs) and microstrip conductors on a quartz substrate. Prior to the development of this amplifier,...

Improved Model of Spectral Response of an HEB Mixer

An improved mathematical model enables the somewhat more accurate prediction of the spectral response of a mixer circuit (see figure) that comprises a twin-slot antenna coupled via coplanar...

Full-Spectrum Arraying of Receiving Radio Antennas

A method of arraying of receiving radio antennas involves utilization of all of the signal information available across a broad spectral band that includes any signal(s) of interest. As used...

Simplified Construction of Conical Log-Spiral Antenna

An improved design for a conical log-spiral antenna (see Figure 1) simplifies construction and improves alignment. The radiating-element substructure of such an antenna must be...

Improved Encryption-Mode GPS Receiver

An improved Global Positioning System (GPS) receiver, which processes an encrypted P-code signal without knowledge of the encryption code (denoted here as A-codeless mode), includes an auxiliary antenna...

Submillimeter-Wave Image Sensor

A proposed monolithic planar array of miniature dipole antennas, diodes, and associated input/output circuitry would serve as a prototype of image sensors for submillimeter-wavelength video cameras (see Figure...

Second-Generation Spaceborne Rainfall-Profiling Radar System

"PR-2" denotes a proposed spaceborne radar system for measuring three-dimensional rainfall profiles and rainfall velocities. The PR-2 system would incorporate a number of...

Improved System for Locating Lightning Strikes Within Meters

A system for determining the locations of nearby lightning strikes from electric-field and acoustic measurements has been developed. This system evolved from the system described...

System Locates Lightning Strikes to Within Meters

A system for determining the locations of nearby lightning strikes from electric-field and acoustic measurements has been developed and built. The system includes at least three receivers,...

Resonant Crackwires for In Situ Monitoring of Jet Engines

Fatigue cracks and plastic deformation of parts in jet aircraft engines could be detected, even during engine operation, by use of proposed in situ monitoring devices called "wireless...

Imaging With a Focal-Plane Array of Ultrasonic Transducers

A prototype system for acoustic imaging of gas leaks that emit ultrasound was developed at Kennedy Space Center. Potential government and commercial users concerned with leak imaging...

Optically Transparent Patch Antennas

Optically transparent patch antennas have been invented for use in communication systems at frequencies of the order of a few gigahertz. These antennas can be mounted on windows of buildings and vehicles,...

Inflatable Reflectarray Antennas

A type of reflectarray antenna now undergoing development is based on the concept of a reflector membrane that is stretched flat by attaching it to an inflatable frame (see figure). Antennas of this type are...

Exploiting Crossed Magnetic Antennas in a Natural Waveguide

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,...

Seven-Element Circularly Polarized Patch Antenna

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...

Processing ScanSAR Data Using a Chirp z-Transform

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...

Inverse Rectennas for Two-Way Wireless Power Transmission

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...

Computation of Characteristics of a Helical TWT Slow-Wave Circuit

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...

Dual-Channel Precision Signal-to-Noise Ratio Generator

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,...

Coplanar-Stripline Transition and Band-Stop Filters

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...

Fabricating Diffusion-Cooled Hot-Electron-Bolometer Elements

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