Electrical/Electronics

PATTERNS: Panoptic Aspect Time Triggered Ethernet Robust Network Scheduler, Version 1.0

Lyndon B. Johnson Space Center, Houston, Texas The PATTERNS scheduling tool was created to test the multi-plane concept of a Time Triggered Ethernet (TTE) network. The TTE network interface cards used in the Orion vehicle contain three physical network ports, referred to as planes. Each plane exists to serve as a redundant communication channel for each link in the network. The scheduler used prior to PATTERNS was the vendorprovided demonstration tool, TTE-demo-scheduler, which was unable to schedule Ethernet traffic in a manner that would allow the plane-specific and plane-independent tests required to be performed.

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An Earth-Observing, Frequency-Agile Radar Receiver for RFI Mitigation

Applications include automotive collision-avoidance radar, cellular phone networks, and radar surveillance sensors for unmanned vehicles. NASA’s Jet Propulsion Laboratory, Pasadena, California The Soil Moisture Active Passive (SMAP) mission will have the first L-band radar/radiometer sensor suite dedicated to global measurements of soil moisture. For the radar sensor, the requirements for achieving high backscatter measurement accuracy from low-Earth orbit present a unique design challenge in the presence of terrestrial radio frequency interference (RFI). The SMAP radar shares the same 1,215 to 1,300 MHz spectrum used by high-power ground-based transmitters like air-route and defense surveillance radars, which can generate strong interference in a conventional fixed-frequency spaceborne radar. The noisy ground environment motivated the development of a frequency-hopping (self-tuning) feature in the radar design. As the SMAP spacecraft orbits across various regions of the Earth, the radar continually adjusts its RF operating frequency to quieter areas of the spectrum for improved fidelity in soil-moisture science data observations.

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Wireless Electrical Devices Using Floating Electrodes

Langley Research Center, Hampton, Virginia A wireless, connection-free, open circuit technology can be used for developing electrical devices like sensors that need no physical contact with the properties being measured. At the core of the technology is the SansEC (Sans Electrical Connections) circuit that is damage-resilient and environmentally friendly to manufacture and use.

Posted in: Electronics & Computers, Sensors, Articles, Briefs, TSP

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Technology-Independent RHBD Library Through Gate Array Approach

All gates in the library are based on one common cell. Goddard Space Flight Center, Greenbelt, Maryland As semiconductor technology nodes scale down, the limitation on polysilicon pitch makes it almost impossible to shrink libraries built for previous technologies. To design a library for a new technology, all of the cells have to basically start from scratch. Starting over for each technology node shrink is time-consuming and expensive. Further, obtaining space qualification for a technology node will require significant time and money. If a RHBD (radiation-hardened-by-design) library gates invention shares the same transistor structured as the SASIC (Structured Application-Specific Integrated Circuit), it will benefit from the existing qualification effort and high-performance advanced technology of the SASIC design flow.

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Advanced Pulse Compression System and Testbed

Industrial applications include 3D machine vision systems that rely on radar for target identification and obstacle avoidance. Goddard Space Flight Center, Greenbelt, Maryland Detection of low-level water clouds from space is one of the outstanding challenges in radar remote sensing. Spaceborne remote sensing is the only means of assessing the distribution and variability of cloud cover on a global basis. Uncertainties in models of the Earth’s heating budget will persist until CloudSat and follow-on missions such as ACE (Advanced Composition Explorer), with enhanced radar capabilities, complete their missions. Detecting weak scatters at lower altitudes presents significant challenges. Millimeter-wave radars offer the only chance to measure these scatters from space. Unfortunately, the peak power available at Ka and W-band — desirable wavelengths for cloud remote sensing — does not provide adequate sensitivity at the resolution required. For many spaceborne radars, pulse compression techniques are used to overcome the limitations in peak power and take advantage of the average power available. But the backscatter from clouds, even at W-band, can be 7 to 8 orders of magnitude weaker than the surface backscatter. In order to use pulse compression techniques, peak range sidelobes need to be suppressed by upwards of 80 dB.

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Fourier Transform Spectrometer on Autonomous Self-Healing Hardware Platform

This liquid crystal waveguide-based platform provides self-healing for electronics in dangerous or hard-to-reach locations. NASA’s Jet Propulsion Laboratory, Pasadena, California The autonomous self-healing (eDNA) hardware platform is a reconfigurable field-programmable gate-array (FPGA)-type platform developed by Technical University of Denmark (patent: WO/2010/060923). It is capable of autonomously reconfiguring itself in case a fault is detected and, thusly, restoring functionality at a fault-free location on the chip.

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Low-Temperature-Compatible Electronics for a Miniature Nuclear Magnetic Resonance Spectrometer

The electronics have been demonstrated to function down to 77 K. NASA’s Jet Propulsion Laboratory, Pasadena, California Missions to Titan are severely limited in available mass and power because spacecraft have to travel over a billion miles to get there, consuming large masses of propellants. Thus low-mass, low-power instruments are a high priority need for Titan missions. A miniature, liquid-phase, high-resolution, pulsed proton-NMR (1H-NMR) spectrometer was developed with low mass (1.5 kg), requiring low power, that can be operated cryogenically on the surface of Titan. This work focuses on new pulsed electronic circuits, optimized for a nuclear magnetic resonance (NMR) spectrometer for analysis of hydrocarbon liquids on Titan.

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