Electronics & Software

A computer program coordinates the activities of multiple instrumented robotic vehicles of the "rover" type intended for use in scientific exploration. The program is a master/slave, distributed version of the ASPEN planning software, other versions of which have been reported in several...

Saxj is a computer program that facilitates the development of programs that parse textual input in the Java programming language. Saxj is a parser generator that creates static Java parsers in the same sense in which YACC, Bison, and YACC++ are static parser generators that create static C-language parsers....

Luthorj is a computer program that creates static lexical analyzers in the Java programming language, in the same sense in which Flex and Lex create lexical analyzers in the C programming language. The majority of users of Luthorj are expected to be familiar with Lex, and Luthorj parses input files that...

Design for X (DFX) is a computer program that assists, at the prelimary stage of planning, in the evaluaiton of alternative spacecraft designs and mission scenarios. The input required by DFX includes a set of operations goals (scientific and engineering goals and constraints), a mathematical...

Diamond Eye is a computer program that enables a user equipped with only a personal computer, web-browser software, and a network connection to analyze large collections of scientific image data. The system is based on a distributed applet/server architecture that provides platform-independent...

Digital Earth Workbench is a computer program that facilitates retrieval of Earth-related imagery and viewing of the imagery on either an ordinary computer video screen or a virtual-reality (head-tracked stereoscopic) display system. Examples of imagery that can be processed bythis software...

A technique of automatic bias compensation has been devised to correct errors caused by variations among electronic components in Global Positioning System (GPS) receivers that use the coarse/acquisition (C/A) GPS code. Even though there are large government and commercial markets for such GPS receivers,...

A multithreading computer program performs phase-retrieval and -unwrapping calculations to extract accurate image phase maps from noisy image magnitude fields generated by adaptive optics. [As used here, "phase retrieval" signifies the calculation of phase map modulo 2µ, while...

The Spectral Analysis Tool (SAT) computer program assists in analysis of interference between radio signals in Earth/spacecraft communications. SAT provides an easy-to-use interactive graphical interface with a menu for selecting among the following utility subprograms: an editor for...

A document in the form of lecture slides outlines a program of development of capabilities for acquisition of signals, tracking of signal sources, and pointing of transmitters and receivers in deep-space optical communications. Topics addressed on the first few slides include the...

The SAR Processing System Raw Data Processor (SPS RDS) computer program is used in the Alaska SAR Facility (ASF) to scan and decode raw data that have been downlinked from the European Remote Sensing Satellite (ERS), the Japanese Earth Resources Satellite (JERS), and the RADARSAT (a Canadian...

The Object Oriented Data Technology group at NASA's Jet Propulsion Laboratory is developing software for locating data — especially scientific data — stored in various formats on heterogeneous computer systems at different locations. The software is intended to exploit and extend...

The term "microGPS" denotes a Global Positioning System (GPS) receiver design concept that combines relatively simple, lightweight, low-power-consumption hardware with portable, efficient software. The power demand of a microGPS receiver can be made low because it is designed to sample sparsely; that is, to...

The Spacecraft Control Toolbox (SCT) helps design control systems and attitude estimators, analyze station-keeping requirements, generate fuel and pointing budgets, and analyze spacecraft dynamics. The SCT provides a comprehensive set of over five hundred functions including:

The RecDel System is a low-cost software application that helps different groups of a complex project negotiate interfaces between interdependent schedules. The RecDel system is based on a concept of distributed planning, wherein the cognizant persons retain control over, and responsibility for, their...

A software package for use in a ground receiving station detects a beacon-monitor tone transmitted by a spacecraft. To recapitulate from previous NASA Tech Briefs articles on beacon monitoring: An onboard computer processes data from onboard sensors to summarize the condition of the spacecraft in...

The Automated Real-Time Spacecraft Navigation (ARTSN) system is a prototype of a class of software systems for automated navigation and monitoring of spacecraft from stations on the Earth. The system processes radio metric tracking data (principally, range and Doppler measurements) in real time to...