Electrical/​Electronics

A laser illuminator system has been developed for use in automated tracking of objects. In its original application, the system illuminates a 5° conical region expected to contain a small satellite at a distance up to 750 m from the space shuttle. If the satellite comes within this region, then a receiving...

An integrated optical voltage-measuring apparatus based on a Mach-Zehnder interferometer has been designed and constructed. The main feature of this apparatus is that optical fibers link part of it to an optical sensor head placed at the source of the voltage to be measured, whether the source be a...

An apparatus records triaxial acceleration and temperature as a function of time, operating unattended for as long as 3 weeks on power supplied by two D cells. The apparatus, which has dimensions of only 3.5 by 4.5 by 2.2 in. (8.9 by 11.4 by 5.6 cm) and weighs only 28.5 oz (0.81 kg) is designed...

A dynamic random-access memory (DRAM) circuit that tolerates single-event upsets (SEUs) has been developed. A single-event upset is a bit flip caused by ionizing radiation. In a DRAM, the state of each bit (0 or 1) is stored as charge on a buried capacitor. The impingement of an energetic charged particle...

Lightweight reflector dishes for radio antennas would be mass-produced cheaply by spin casting of polymers, according to a proposal. These reflector dishes were conceived for compact stowage followed by deployment and operation aboard spacecraft, but might also be useful on Earth in...

A retroreflective communication system (RCS), is a state-of-the-art system that provides (1) two-way optical communication using only one transmitter and (2) multipath communication among remote locations. RCSs were conceived for use in communication among stations on the ground and aboard spacecraft in...

An algorithm for filtering synthetic-aperture-radar (SAR) interferograms has been developed which substantially improves the performance of subsequent phase-unwrapping. It accomplishes this task by filtering the interferogram strongly in areas where the scene contains little detail, and weakly where the...

The forward-link/simulator card (FLS) performs the fundamental satellite-telemetry data-transmission function for the forward (Earth-to-spacecraft) link in real time at rates up to 400 Mb/s. The FLS also simulates a Consultative Committee for Space Data Systems (CCSDS) telemetry data source that outputs data at rates...

Two reports present further developments in the subject of "Computation of Characteristics of a Helical TWT Slow-Wave Circuit" (LEW-16571), NASA Tech Briefs, Vol. 22, No. 4 (April 1998), page 54. The subject is computation, by use of the MAFIA (Solution of MAxwell's Equations by the...

Piezoelectric devices that would serve as spark plugs, power generators for spark plugs, and/or pressure sensors have been proposed for use in internal-combustion engines. Unlike conventional spark plugs, these devices would function without need for wire connections to external high-voltage sources....

A method of preprocessing lightning-measurement waveforms has been devised to reduce the bandwidth needed to transmit data for computing the locations of lightning strikes. The method is used in a system in which electric fields and electric-field derivatives induced by lightning are...

The Materials Science Division (MSD) at Kennedy Space Center is developing a computer system to maintain a material-science data base coupled with a user-friendly interface on the World Wide Web. The system is designed to eliminate the need for time-consuming and expensive distribution of,...

Never before have secondary schools been able to post-process raw satellite data, and now they can do it in real time. This is credited to advances in technology that have recently made the necessary equipment simple, inexpensive, powerful, and available enough for any school to fit into...

The return-link processor card (RLP) performs all of the fundamental data-processing functions involved in the return of satellite telemetry, in real time at rates up to 400 Mb/s, using industry-standard interface circuitry and connectors with standard sizes and shapes. Previously, four cards, each containing a...

A report presents additional information on the Mechanical System Design/Analysis Tool (MSAT) computer program, which was reported in "Program for Designing a Mechanical System" (LEW-16710, NASA Tech Briefs, Vol. 23, No. 9 (September 1999), page 32. To recapitulate: MSAT is a user-friendly, multidisciplinary software system that...