Two documents discuss a breadboard version of advanced transponders that, when fully developed, would be installed on future spacecraft to fly in deep space. These transponders will be required to be capable of operation on any deepspace-communications uplink frequency channel between 7,145...

A document presents additional information on the means of implementing a capability for wide tuning of microwave receiver and transmitter frequencies in the development reported in the immediately preceding article, "VCO PLL Frequency Synthesizers for Spacecraft Transponders" (NPO-42909). The...

A paper discusses general problems in estimation and control of the states (positions, attitudes, and velocities) of spacecraft flying in formation, then addresses the particular formation-flying-control problem of synchronization of deadbands. The paper presents a...

A team of JPL researchers has analyzed stereoscopic vision software and produced a document describing its performance. This software is of the type used in maneuvering exploratory robotic vehicles on Martian terrain. The software in question utilizes correlations between portions of the...

A paper presents a method of utilizing some flight data, aboard a spacecraft that includes reaction wheels for attitude control, to estimate the inertia matrix of the spacecraft. The required data are digitized samples of (1) the spacecraft attitude in an inertial reference frame as measured, for...

A short document summarizes the redesign of a xenon-ion spacecraft thruster to increase its operational lifetime beyond a limit heretofore imposed by nonuniform ion-impact erosion of an accelerator electrode grid. A peak in the ion current density on the centerline of the thruster causes...

A report discusses an algorithm for an onboard planning and execution technology to support the exploration and characterization of geological features by autonomous rovers. A rover that is capable of deciding which observations are more important relieves the engineering team from much of the burden...

Curtiss-Wright Controls Embedded Computing (Leesburg, VA) offers the SVME/DMV-1901 6U VME single-board computer with the Intel® Core™ Duo processor running at speeds of 1.67 and 2.0 GHz.

For the last 20 years we have connected our monitors to our computer systems having the confidence that upon turn-on, we could surf or create with never a consideration of whether the display would operate satisfactorily. VGA (Video Graphics Adaptor) technology enabled us to do that with CRTs as well...

An optical filter consisting of a multilayer spectral coating on a flexible membrane has been designed to be placed in front of the 200-in. (5.08-m) Hale telescope on Mt. Palomar. The filter is intended to protect the telescope against solar radiant flux and limit solar heating of the interior of the telescope dome...