New technologies in power supplies and management, board-level electronics, electronics and computers, and battery systems provide wide-ranging applications essential to military, aviation, medical, and automotive.

Briefs : Electronics & Computers
Improved Two-Wavelength Focal-Plane Array of QWIPs

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 between image intensities at the two wavelengths, one can calculate the temperatures of imaged objects by...

Briefs : Electronics & Computers
Delta-Doped CCDs for Measuring Energies of Positive Ions

Research closely related to that reported in the preceding article has shown that δ-doped charge-coupled devices (CCDs) could be used to detect incident protons and perhaps other positive ions, and to measure the kinetic energies of the ions, down to about 1.25 keV. Prior to the...

Briefs : Electronics & Computers
Delta-Doped CCDs as Low-Energy-Particle Detectors

Charge-coupled devices (CCDs) of a type developed previously for imaging in ultraviolet light have been found to be useful as detectors of electrons and other charged particles with kinetic energies as low as about 100 eV. Heretofore, solid-state electronic devices have generally not been useful...

Briefs : Electronics & Computers
Hardware-Command-Decoding ASIC

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 the ASIC is a portion of the spacecraft uplinkprotocol specified in the widely used Consultative Committee...

Briefs : Electronics & Computers
Instrument Records Electric Fields Generated by Lightning

A portable, self-contained, compact instrument measures and records transient electric fields generated by nearby lightning strikes. This instrument complements, and in many respects is similar to, the one described in "Instrument Records Magnetic Fields Generated by Lightning"...

Briefs : Electronics & Computers
Column-Loading Input Chip for Neural-Network Module

The column-loading input chip (CLIC) is a conceptual integrated-circuit chip that would serve as an interface between (1) any of various sources of image data and (2) a three-dimensional analog neural network (3DANN) of the type described in "Neural-Network Modules for High-Speed Image...

Briefs : Electronics & Computers
DC-Excited Thermostrain-Gauge Signal-Conditioning Circuit

The figure illustrates a dc-excited Anderson-loop circuit that includes (1) thermocouples for measuring the temperature of the strain gauge and (2) a signal-conditioning circuit that separates the temperature and strain-gauge signals in the sense that one output voltage is proportional...

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 : Electronics & Computers
Lightweight, Radiation-Resistant EMI Shields

Due to their low density and exceptionally high strength and modulus, graphite fiber composites are being used increasingly for the fabrication of aircraft and spacecraft. Because of their superior mechanical properties, these composites have been replacing metals, such as aluminum alloys, in many...

Briefs : Electronics & Computers
Performance of a Soft Digital-Data-Transition Tracking Loop

A report discusses the performance of a soft digital-data-transition tracking loop (DTTL) in a radio receiver that recovers digital data conveyed by binary phase-shift keying. The DTTL is used as a symbol synchronizer; it provides symbol timing to essential parts of the receiver. The...

Briefs : Electronics & Computers
Computer System for Managing Construction Projects

An automated system of computer hardware and software has been developed for managing construction projects at Stennis Space Center. This system replaces an older collection of paper-based subsystems, wherein documents were copied, filed, and distributed in labor-intensive processes. Data...

Briefs : Electronics & Computers
ASIC Physical Layout for the HCD ASIC

An integrated circuit (IC) physical layout has been developed for the HCD ASIC - an application-specific integrated circuit that decodes digital command signals transmitted from a ground station to a spacecraft (uplink commands). The HCD ASIC is described in "Hardware-Command-Decoding ASIC" (NPO-19615),...

Briefs : Electronics & Computers
ASIC for Reed-Solomon Coding and Related Functions

The Reed-Solomon downlink application-specific integrated circuit (RSDL ASIC) performs Reed-Solomon encoding of telemetry data, internally generates all timing and control signals necessary for the RS encoder, transfers frames of encoded data to a radio transmitter, and performs ancillary...

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
Optoelectronic System Measures Tile Cavities

A hand-held optoelectronic shop tool measures cavities of the order of 6 in. (15 cm) in length and width, 2 to 4 in. (5 to 10 cm) in depth, with nominally flat side walls, and either curved or flat outer and inner surfaces. The system is called the Tile Cavity Measurement System (TCMS) because in the...

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
Bounceless Switch/Monostable Multivibrator

A circuit has been designed to debounce a mechanical switch, which is used to activate a digital circuit. Contacts tend to make and break connections several times until the switch contacts settle out. The repetitive activity plays havoc with digital circuits because more than one state condition could...

Briefs : Electronics & Computers
Better Electrochemical Profiling of III -V Semiconductors

An etching and electrolyte solution called "UNIEL" has been found to be useful for electrochemical characterization as a function of depth ("electrochemical profiling" for short) of semiconductor compounds of elements from periods III and V of the periodic table; that is, InP- and...

Briefs : Electronics & Computers
More Uses for Brillouin Amplification

Some additional applications have been proposed to exploit amplification by stimulated Brillouin scattering ("Brillouin Amplification" for short), building on the concepts introduced in the preceding article. Chief among the proposed applications is conversion of a phase-modulated optical signal to an...

Briefs : Electronics & Computers
Computer System for Collection of Quality-Assurance Data

The Paperless Procedure System (PPS) is a computer-based, semiautomated electronic system for collection and management of quality-assurance data in a large organization. The original version of PPS was designed for use by Kennedy Space Center personnel engaged in inspection tasks during...

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
Automated Vision System Inspects a Large Surface

The figure schematically illustrates an automated electronic vision system that operates in conjunction with a scanning robot to inspect a large surface for damage. In the original application for which the system was developed, the surface comprises the panels of the space shuttle thermal...

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
Fabrication of Arrays of Large Step-Free Regions on Si(100)

When a silicon wafer is cut from an ingot, it is essentially impossible to align the cut perfectly with the crystal structure. Therefore the surface contour of the wafer will be a flat plane on which terraces consisting of additional atomic layers will be scattered. An atomic step will...

Briefs : Electronics & Computers
Reflective Coating System for High-Temperature Vacuum Use

A substrate of nickel coated with a thin layer of silver and further coated with a thin protective layer of silicon dioxide has been found to constitute an optically reflective substrate/coating system that is suitable for use at high temperature in vacuum. This system was developed...

Briefs : Electronics & Computers
Extracting Misalignments of Layers in Microfabricated Devices

Two closely related methods of optical inspection and computation yield data on misalignments between critical features in different layers of microfabricated devices. Examples of such devices containing features in different layers that are required to be aligned with each other...

Briefs : Electronics & Computers
Optoelectronic Oscillators Based on Brillouin Scattering

An improved type of optoelectronic oscillator is based on Brillouin amplification. An oscillator of this type converts light energy into an electro-optical oscillation, typically at a frequency of several gigahertz. It offers several advantages over other electro-optical and over...

Briefs : Electronics & Computers
Exploiting Brillouin Scattering in Analog Signal Processing

Stimulated Brillouin Scattering (SBS) in optical fibers can be exploited to obtain frequency conversion with amplification and frequency-selective amplification in photonic signal-transmission and signal-processing systems. SBS has been found to be particularly useful in photonic...

Briefs : Electronics & Computers
Impedance-Based Cable Tester

The figure illustrates the major functional blocks of an impedance-based cable-testing apparatus that can locate an open or short circuit in a cable. There is no need to disconnect the cable from all other equipment in preparation for a test – an advantage in a system in which cable connections are located in...

Briefs : Electronics & Computers
Low-Frequency Signal-Pickup Cable Tester

A cable-testing apparatus has been designed for use in detecting a short or open circuit in a cable, subject to a special frequency requirement as explained in the next paragraph. This cable tester is based on the injection of a signal at one end of the cable and the use of a pickup coil placed adjacent...