Electrical/​Electronics

Nickel-hydrogen electrochemical cells with capacities of 350 ampere-hours have been developed. These cells are intended primarily for use in government and commercial satellites; they have been fully qualified to satisfy performance requirements for operation in geosynchronous satellites for as long as 15 years....

A report presents some results of continuing efforts to develop advanced thermoelectric devices and, more particularly, thermoelectric unicouples for generating electric power from diverse thermal sources, including automotive exhausts and other waste-heat sources. The basic principles of...

A report proposes a method of cooperative modulation between (1) low-power radio transceivers associated with sensors geographically dispersed on a remote planet for relaying information between the sensors and an Earth station. The method, denoted node selection on orthogonal...

A report describes an application-specific integrated circuit (ASIC) for controlling a power-switching metal oxide semiconductor field-effect transistor (MOSFET) in a spacecraft power-supply system. Denoted an SCA (for switch-control ASIC), this ASIC is designed to be radiation-hard and to...

The Meteorological Range Safety Support System/Eastern Range Dispersion Assessment System (MARSS/ERDAS) is a system of interconnected computer workstations designed to acquire, process, and disseminate nearly real-time meteorological data and outputs of mathematical models of the atmospheric...

An improved charge-termination technique has been developed to obtain a more accurate balance between charge and discharge of rechargeable lithium-ion-based electrochemical cells and batteries. The technique has been demonstrated experimentally and is now in use in a laboratory battery...

An algorithm that can discover potentially interesting objects in image data has been formulated and implemented in software. The algorithm is intended for applications in which the target objects are mathematically ill-defined and/or not known or specified in advance. Potential applications include...

An Automated Test Case Generator computer program generates parameter-based test cases for testing software and hardware systems. Given N parameters — each of which represents a kind of variation for testing — and a finite set of possible values for each parameter, the program generates individual...

An article discusses anticipated advances in the design of increasingly capable integrated circuits containing ever smaller electronic devices. The article emphasizes the emergence of technology computer-aided design (TCAD) — a discipline in which computer-aided design is combined with computational...

Some improvements have been made in an instrument designed expressly for recording lightning-induced transient voltages on power and signal cables. The instrument as it existed prior to the improvements was described in "Fast Transient-Voltage Recorder" (KSC-11991), NASA Tech Briefs, Vol. 23, No....

A report describes the NASA Spacecraft Transponding Modem (STM) — a spacecraft transponder now under development for planned use on deep-space missions scheduled for launch in the year 2003. In comparison with a traditional deep-space transponder, the STM will be smaller and less power hungry; the reductions...

The design of a highly reliable controller for a digital data bus incorporates improvements, in both hardware and software, over the basic design of a low-speed, low-power, serial bus known in the industry as "I2C." ("I2C" signifies "inter integrated circuit bus" — a bus developed by Philips...