Keyword: Radiation

Briefs: Electronics & Computers

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,...

Briefs: Electronics & Computers
Data-Acquisition System Takes 8-Bit Samples at 1 GHz

A unique data-acquisition system converts analog input voltages to 8-bit digital data at a rate as high as 109 samples per second (1 GHz), stores the data, and makes the data available for further processing. The system is compact, is highly resistant to ionizing radiation,...

Briefs: Electronics & Computers
Improved Lightning-Current Measurements on a Protective Wire

A test procedure has been devised to increase the accuracy with which lightning currents on a protective wire can be determined from raw current measurements. The procedure was conceived specifically for determining lightning currents on a steel cable used to protect the space shuttle...

Briefs: Electronics & Computers

Focal-plane arrays of active-pixel sensors (photodetectors integrated with in-pixel readout transistors) would be designed and fabricated within the emerging technological discipline of...

Briefs: Electronics & Computers

A recently developed gallium nitride-based linear array of ultraviolet detectors is blind to most of the visible spectrum, with a cutoff wavelength of 370 nm. This device is a prototype of GaN...

Briefs: Electronics & Computers
Circuit for Automatic Tunneling-Controlled Golay Cell

An automatic tunneling-controlled, micromachined Golay cell has been implemented in a multichip integrated-circuit module. The module is designed specifically for sensing infrared radiation indicative of the concentration of glucose in blood, but its low noise, high gain, and low power...

Briefs: Electronics & Computers
High-Performance HgCdTe Detectors for Remote Sensing: Part 1

Focal-plane arrays of HgCdTe photoconductors have been designed and fabricated to satisfy special requirements for high-performance long-wavelength infrared (LWIR) photodetectors. The special requirements are the following:

Briefs: Electronics & Computers

Several microwave-cavity devices at various stages of development are designed for heating material samples or process streams with uniform temperature-versus-time histories. These devices...

Briefs: Electronics & Computers

This filter closely approximates the desired wave shape, regardless of the bit rate.

Briefs: Electronics & Computers

A Magnetic Random-Access Memory (MagRAM) is an array of bistable magnetic memory elements with semiconductor amplifier and addressing circuitry. MagRAMs are in the early stages of development, which has been...

Briefs: Medical
Neutrophil-Screening Assay Using Two-Color Flow Cytometry

An in vitro test that includes the use of two-color flow cytometry has been developed for use in screening of neutrophils for their ability to fight infections. Neutrophils constitute the first line of defense of the human body against infections. Neutrophils engulf invading bacteria in a...

Briefs: Electronics & Computers
Eight-Channel WDM Fiber-Optic Data-Communication System

A proposed wavelength-division-multiplexing (WDM) optical communication system would feature a single optical fiber carrying eight channels of digital data signals. In the original application, the signal in each channel would be a serial digital video-camera output, but the system could...

Briefs: Photonics/Optics
Computer Code for Analysis of Stress in Silicon Wafers

The MacWafer™ code computes gravitational and thermal stresses in silicon wafers and uses these results to determine the maximum allowable temperature variation across a wafer, maximum processing temperatures, and maximum allowable heating and cooling rates. This information is of...

Briefs: Materials

A microwave-heating technique has been developed for making a braze joint (1) between a tungsten carbide support and a surface layer of polycrystalline diamond or, alternatively,...

Briefs: Electronics & Computers

"Free-Space Optical Communications Analysis Software" (FOCAS) is the name of a spreadsheet computer program for analysis of direct-detection (as distinguished from...

Briefs: Test & Measurement

A multiwavelength pyrometric technique estimates the surface and bulk (subsurface) temperatures of a hot glass. The multiwavelength pyrometer for which the technique was developed...

Briefs: Electronics & Computers
Micromachined Photodiode/Bolometer Arrays

Micromachined planar arrays of detectors that could operate either as photodiodes or as bolometers have been proposed for use in detecting photons in applications in which broad spectral responses are required. The availability of either of the two modes would enable operation throughout the spectrum,...

Briefs: Electronics & Computers

A concept for optimizing the designs of two-wavelength GaAs-based quantum-well infrared photodetectors (QWIPs) could make it practical to use focal-plane arrays of QWIPs as image sensors...

Briefs: Physical Sciences
Transparent Furnaces for High-Temperature Research

Transparent furnaces are being developed for use in research on properties and processing of materials at high temperatures. Full optical access to the interiors of furnaces is intended to provide the capability for nonintrusive diagnosis and feedback control of the subtleties of...

Briefs: Electronics & Computers
Self-Checking Circuitry for Detecting Single-Event Latchups

High-performance electronic circuits would incorporate self-checking features for detection of radiation-induced single-event latchups (SELs), according to a proposal. The basic SEL-detection scheme calls for redundant circuitry and a current-voting scheme similar to voting schemes...

Briefs: Electronics & Computers

A focal-plane array (FPA) of GaAs-based quantum-well infrared photodetectors (QWIPs) that would detect images in two wavelength bands simultaneously is undergoing development. From ratios...

Briefs: Electronics & Computers

A hardware-command-decoding application-specific integrated circuit (HCD ASIC) is designed to decode digital command signals transmitted from a ground station to a spacecraft (uplink commands). Implemented in...

Briefs: Physical Sciences
Solar/Infrared Aerobots for Exploring Several Planets

A report discusses a class of balloon-borne robotic instrumentation systems that have been proposed for use in exploring Venus, Jupiter, Saturn, Uranus, and Neptune. The balloons would be of the Montgolfier type; that is, buoyancy would be achieved through heating of atmospheric gases...

Briefs: Electronics & Computers
Micromachined Tunneling Accelerometer for Use in Outer Space

Two short reports describe a micromachined quantum-mechanical-tunneling accelerometer and radiation-hardened support electronics designed for use in outer space. Like the micromachined tunneling accelerometers described previously in NASA Tech Briefs, this device is based on the use...

Briefs: Electronics & Computers
Plasma Window Technology for Propagating Particle Beams and Radiation from Vacuum to Atmosphere

Plasma windows can separate vacuum and atmosphere, or regions of high and low vacuums, in a way which facilitates transmission of various particle beams and/or radiation from low- to high-pressure regions. In a prototype device, a stabilized plasma...

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: Physical Sciences

The figure illustrates a solar thermal energy system for boiling water or another liquid. The system can be used for a variety of purposes that can include drying aqueous hazardous...

Briefs: Manufacturing & Prototyping

A friction stir weld (FSW) system for welding and weld repair can be used on the manufacturing floor, as well as in the laboratory environment. This FSW system can be used in a wide...