Communications

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...

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...

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...

NASA's Jet Propulsion Laboratory (JPL) has developed a compact, low-power, self-contained instrument that provides the equivalent of GPS throughout the solar system without the aid of an artificially provided infrastructure. The state-of-the-art X-ray navigation instrument is also able to determine the position of a...

NASA seeks interested parties to license the Ad Hoc Selection for Voice Over Internet (VoIP) Streams technology developed by engineers at Johnson Space Center. This technology features the ability to select specific audio streams from one or more sources and then convert them into a multicast to the...

The purpose of the GPS Satellite Geometry Analysis Tool (GPSGEM) is to evaluate GPS satellite geometry for a given Earth-fixed location or for a provided trajectory. The tool will generate a listing of all satellites in view, the best satellite combination defined by the most optimum Geometric Dilution...

Heterogeneous Spacecraft Networks (HSNs) are network environments in which spacecraft from different missions and institutions can communicate with each other at a low cost and with low impact on overall system resources. The technology of heterogeneous wireless networks has yet to be extended to space networks,...

The purpose of this invention is to provide a novel, low-loss, dual-band reflectarray element design that is transparent and low-loss across one frequency band (Ka-band in the initial application), and provides the phasing and beam collimation capability...

Geomagnetic storms drive geomagnetically induced currents (GICs) in high-voltage power transmission systems. GICs thus carry information about the near-space environment conditions. The U.S. high-voltage power transmission system was used as an extremely large antenna to...

The Magnetospheric Multiscale (MMS) mission is the fourth mission of the Solar Terrestrial Probes (STP) program. The MMS mission, consisting of four identically instrumented spacecraft, will use Earth’s magnetosphere as a laboratory to study magnetic reconnection, a fundamental...

Operators of the Deep Space Network (DSN) attend to numerous tasks with the overall goal of providing continuous support for the world’s deep space missions. This high-stakes operations environment requires operators to understand the state of the DSN and predict...

The bit error rate (BER) is a wellunderstood metric for measuring communications system performance. When a system is not amenable to analytical performance analysis, a Monte Carlo simulation is often used to determine the performance. In such simulations, it is necessary...

Secure communication over long distances requires robust encryption. While current encryption algorithms exist using classical methods, there are no unconditionally secure methods of distributing encryption keys classically. However, by exploiting...

This software provides a portable, flexible memory testing application meeting the NASA Space Telecommunications Radio System (STRS) specification. As an STRS-compliant application, the tester application is portable to any STRS-compliant hardware/software platform. Thanks to...

Dynamic frame sizing was added to the existing AOS Packet Service FPGA implementation. This capability provides in-flight system calibration functionality, allowing the spacecraft and ground station the means to optimize a communication link by...

In high-latency, low-bandwidth networks such as those employed when communicating with an extraterrestrial object via wireless communication over hundreds or thousands of miles, it may be difficult or expensive to communicate large quantities of information in a reliable...

Secure, efficient, and effective communication is critical for the multinational Cassini mission to Saturn. Cassini teams share information through the use of internal Web pages. The challenge was to develop dynamic Web pages that did not require special understanding of HTML complexities and the...

In response to the requirements of the Space-Based Relay Study (SBRS) undertaken by NASA in 2013, as well as the Integrated Radio and Optical Communications (iROC) project being conducted by NASA Glenn Research Center (GRC) beginning in 2012, a calculation procedure was required to rapidly assess the operation of...

GPS signals are sparse and weak at high altitudes above the GPS constellation; this includes GEO and HEO orbit regimes. Spacecraft operating here need a high-sensitivity receiver capable of acquiring and tracking these weak signals throughout their orbits. Most space GPS receivers are...

Low-Density Parity-Check (LDPC) codes are a class of forward error correction (FEC) linear block codes that provide near-capacity performance for power-efficient communications. Optimum decoding requires accurate combining ratio estimation to scale the...