Electromagnetic Waves Transformed from a Coherent to a Quasi-Coherent Nature

NASA’s Jet Propulsion Laboratory, Pasadena, California The transformation of naturally occurring electromagnetic waves called “chorus” from a coherent nature to a quasi-coherent nature when propagating a distance from its source was demonstrated. The aim of the mission was to study the energizing of electrons by the waves and also the loss of these particles by interaction with the waves. Both of these processes will be affected by the quasi-coherent nature of chorus. This work indicates that if coherent waves are not propagated in enhanced ionization ducting, the waves will become only quasi-coherent, and their effect of scattering trapped particles will be substantially diminished.

Posted in: Articles, Briefs, Electronics & Computers


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.

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


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


Web-Enabled and Automatic Ground Processing Infrastructure Servicing the UAVSAR Airborne Missions

NASA’s Jet Propulsion Laboratory, Pasadena, California The UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar) ground data processing infrastructure facilitates a wide range of mission operational processes through a centralized database, Web-enabled interfaces, and background automation. By tracking flight request submissions and flight planning activities, the database provides the most up-to-date historical records on how and when flight missions took place, as well as what radar data were collected. As data-collection missions wrap up, post-mission reports are uploaded to the database via a Web interface, while raw data are scanned into the database enabling the operator to perform polarimetric/interferometric processing on the radar data.

Posted in: Articles, Briefs, Aeronautics, Aviation, Electronics & Computers, Data Acquisition


Wireless Devices Used by Pilots are Vulnerable to Hacking

A new class of apps and wireless devices used by private pilots are vulnerable to a wide range of security attacks, which in some scenarios could lead to catastrophic outcomes, according to computer scientists at the University of California, San Diego and Johns Hopkins University. They examined three combinations of devices and apps most commonly used by private pilots to access the same information available to the pilot of a private jet at a fraction of the cost. All have to be paired with tablet computers to display information.

Posted in: News, Aerospace, Aviation, Communications, Defense, Electronics & Computers, PCs/Portable Computers


NASA Advances Next-Generation 3D-Imaging Lidar

Building, fixing, and refueling space-based assets or rendezvousing with a comet or asteroid will require a robotic vehicle and a super-precise, high-resolution 3D imaging lidar that will generate real-time images needed to guide the vehicle to a target traveling at thousands of miles per hour. A team at NASA’s Goddard Space Flight Center is developing a next-generation 3D scanning lidar — dubbed the Goddard Reconfiguable Solid-state Scanning Lidar (GRSSLi) — that could provide the imagery needed to execute these orbital dances. GRSSLi is a small, low-cost, low-weight platform capable of centimeter-level resolution over a range of distances, from meters to kilometers. Equipped with a low-power, eye-safe laser; a MEMS scanner; and a single photodetector, GRSSLi will "paint" a scene with the scanning laser, and its detector will sense the reflected light to create a high-resolution 3D image at kilometer distances. A non-scanning version of GRSSLi would be ideal for close approaches to asteroids. It would employ a flash lidar, which doesn’t paint a scene with a mechanical scanner, but rather illuminates the target with a single pulse of laser light — much like a camera flash. Source:

Posted in: News, Aerospace, Electronics & Computers, Imaging, MEMs, Lasers & Laser Systems, Photonics, Machinery & Automation, Robotics


Researchers Develop a Way to Control Material with Voltage

A new way of switching the magnetic properties of a material using just a small applied voltage, developed by researchers at MIT and collaborators elsewhere, could signal the beginning of a new family of materials with a variety of switchable properties. The technique could ultimately be used to control properties other than magnetism, including reflectivity or thermal conductivity. The first application of the new finding is likely to be a new kind of memory chip that requires no power to maintain data once it’s written, drastically lowering its overall power needs. This could be especially useful for mobile devices, where battery life is often a major limitation.

Posted in: News, Batteries, Board-Level Electronics, Electronic Components, Electronics & Computers, Power Management, Materials, Metals, Semiconductors & ICs


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