Electrical/​Electronics

Neural networks of a proposed type would be formed with computational units called "neuromorphs" attached in a locally connected array. These neural networks would achieve pattern recognition invariant under rotation and translation by exploiting a combination of network symmetry and...

Cross-correlated trellis-coded quadrature modulation (XTCQM) has been proposed as a generic scheme with specific embodiments that potentially offer superior alternatives to other highly power- and bandwidth-efficient phase-shift-keying (PSK) modulation schemes. Examples of such schemes include...

A low-power, miniature Doppler lidar instrument is being developed for use in measuring opacity (from dust) and wind profiles in the Martian atmosphere. The instrument could also be used on Earth to measure turbulence in the atmospheric boundary layer, for assessments of urban and regional air...

Improved passive temperature-compensating attenuators have been developed for use in processing radio signals at frequencies up to about 18 GHz. In general, temperature-compensating circuits and devices are needed to minimize (preferably, to eliminate) undesired temperature dependences of the...

Miners today use externally powered machines designed to be used by a single operator, the autonomous miner. Many companies offer computer-operated mining equipment that can be used for both high wall and underground applications. Programmable logic controls with ring laser gyroscopes and inclinometers...

A prototype dual-polarization microstrip patch rectenna dimensioned for an operating frequency of 8.51 GHz has been built to demonstrate a design concept for obtaining maximum output voltage from a rectenna of a given size. This rectenna contains nine square microstrip patch antenna elements in a...

An algorithm has been developed for a computer-based electronic system that would aid human ground controllers in monitoring data from sensors in the electric-power system of the International Space Station. Among other things, the algorithm encodes knowledge of human experts; thereby harnessing...

A portable electronic unit with no moving parts except button switches digitizes and stores a 48-hour record of the myoelectric activity of the stomach and heart as sensed via electrodes on the surface of the abdomen. Just as the more familiar electrocardiogram (ECG) is useful in diagnosing the condition of the heart,...

Carbon nanotubes (also known as "bucky tubes") have shown promise for use as anode materials in rechargeable lithium-ion power cells. In comparison with graphite and other forms of carbon used under identical conditions, bucky tubes exhibit greater specific discharge capacity and greater...

High-speed complex-amplitude spatial light modulators (SLMs) containing liquid crystals with pixel electronic circuitry on single-crystal-silicon backplanes are undergoing development. The basic approach taken in this project is to use fast-switching liquid-crystal materials and modulation-enhancing...