Communications

Personal Annunciation Device (PAD)

The PAD can be used where chemical, biological, or other hazards are present, and traditional notification means are not adequate.

Many industrial and commercial plants, government and private research facilities, and industrial facilities perform potentially dangerous processes. Automated warning and alarm systems alert personnel to dangerous or abnormal conditions inside or near a plant so the personnel may take prompt protective action such as evacuation, co-location, or shelter in place. Such automated systems include simple fire and smoke detectors that detect the presence of fire or smoke and immediately activate a connected, audible alarm confined to a specific area of a plant. Many systems include a central hub for receiving detection signals from detectors located throughout a plant. In some systems, the central hub also is connected to a network of alarms including audible alarms — both siren-like and information-based — and visual alarms, including flashing emergency lights and textual-based information screens.

Posted in: Briefs, Communications
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Mobile Underwater Acoustic Communications

This invention does not require any complicated signal processing.

Reliable, long-range acoustic communications (LRAC) is an enabling technology for numerous applications of manned and unmanned underwater systems. For example, with the capability of communicating at long ranges of several hundreds or even thousands of kilometers, it will become possible to remotely command and control unmanned underwater vehicles that are otherwise unreachable. As another example, underwater systems will be able to rely on such capability to establish a wide-area undersea network to complete missions in a collaborative fashion.

Posted in: Briefs, Communications
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A Smooth-Walled Feedhorn with Sub-30-dB Cross-Polarization Over a 30-Percent Bandwidth

The focus of this research was the design, optimization, and measurement of a monotonically profiled, smooth-walled scalar feedhorn with a diffraction-limited ~14° FWHM (full width at half maximum). It is an easier-to-manufacture, smooth-walled feed that approximates the properties of excellent beam symmetry, main beam efficiency, and cross-polar response over wide band-widths, but over a finite bandwidth.

Posted in: Briefs, Communications
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Wireless Virtual Reality Headset

This system allows VR headsets to communicate without a cord.

One of the limits of today's virtual reality (VR) headsets is that they must be tethered to computers in order to process data well enough to deliver high-resolution visuals. Wearing an HDMI cable reduces mobility, and can even lead to users tripping over cords. Researchers have developed a prototype system called MoVR that allows use of any VR headset wirelessly.

Posted in: Briefs, Communications
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Wideband Retroreflector

There are many known methods of retransmitting radio wave signals intra-building and inter-building, as well as ground-to-aircraft or ground-to-satellite. Some techniques modulate the reflection coefficient of an antenna. Prior art has used frequency multiplication or field effect transistor (FET) mixing to modulate the reflection coefficient of an antenna, and therefore the reflected amount of incident power to perform this function. This method is limited by its instantaneous bandwidth to about 50 MHz and its overall efficiency, in addition to the tendency to produce large amounts of harmonics. Other techniques include optical retroreflectors and RFID transponders. Optical retroreflectors reflect the illuminating energy; RFID transponders use a fixed RF frequency with resonant circuits.

Posted in: Briefs, Communications
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Technical Webinar Series from the Editors of SAE: Connected Vehicles & Jobsites

In Conjunction with SAE

Fleet owners have been deploying telematic solutions for some time, but connectivity is still just beginning to move from early adopters to mass market. Connectivity is providing more owners and operators a broad range of benefits, prompting a surge of developments by OEMs and suppliers. Chief among those benefits are safer, more efficient, and productive vehicles and worksites, both on- and off-highway. Yet technical challenges remain with development and testing of V2X communication, cybersecurity, and how to best utilize Big Data.

Posted in: Upcoming Webinars, Communications, Wireless
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Printed Electronics Primer: an Introduction to the Basics of Printed Electronics

This white paper provides an overview of how printed electronics (PE) can help you fit more functionality into smaller spaces, while maximizing cost efficiency. You will learn the basic terminology and gain an understanding of today’s PE industry, including prevalent technologies, materials and manufacturing processes.

Posted in: White Papers, Communications, Electronics & Computers, Medical
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Polarization-Dependent Whispering Gallery Modes (WGMs) in Microspheres

WGMs can benefit sensors used in aerospace vehicle control, health and performance monitoring, optical communications, and biological applications.

Dielectric microspheres are optical structures that exhibit resonant properties, meaning they can be used to select very narrow wavelengths of an incoming light beam's spectrum for further manipulation and processing. The optical resonances of a microsphere are frequently called morphology dependent resonances (MDRs) or whispering gallery modes (WGMs). Innovators at NASA's Glenn Research Center have developed a method of separating low-level modes propagating in an optical fiber through the use of WGMs in spherical resonators. The unusually high quality factors (Q-factors) that can be achieved by side coupling of light into the dielectric spheres allow for measurement sensitivities that may far exceed those of more conventional sensors. Whispering gallery modes’ high sensitivity to environmental conditions and their small size make them good candidates for a wide range of sensors.

Posted in: Briefs, Communications, Antennas, Fiber optics, Sensors and actuators
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Cellular Reflectarray Antenna and Method of Making Same

A simple-to-install design for satellite and communications applications solves the problems associated with traditional parabolic reflectors.

NASA's Glenn Research Center invites companies to license a new concept design for terrestrial satellite dishes and communications systems. The Cellular Reflectarray Antenna (CRA) has been developed and tested for use with next-generation Ka-band satellites, although it can be used with all bands of satellite communication. The design's flat, planar configuration all but eliminates the wind-loading problems associated with larger parabolic reflectors for dish systems. The technology also offers unique features that provide ease of installation and improved signal reception, while deterring piracy and theft of subscription satellite services.

Posted in: Briefs, Communications, Antennas, Cyber security, Wireless communication systems, Satellites
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9-Meter Slaving System

The objective of the 9-Meter Slaving System is to transmit Launch Trajectory Acquisition System (LTAS) data from one of multiple incoming data streams to the 9-Meter antenna control unit using a synchronous serial modem. The data stream is determined by a 9-Meter telemetry operator's selection via a graphical user interface (GUI).

Posted in: Briefs, Communications, Trajectory control, Antennas, Telemetry, Entry, descent, and landing
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