|Next-Generation NASA Earth-Orbiting Relay Satellites: Fusing Optical and Microwave Communications|
David J. Israel, Harry Shaw
NASA is currently considering architectures and concepts for the generation of relay satellites that will replace the Tracking and Data Relay Satellite (TDRS) constellation, which has been flying since 1983. TDRS-M, the last of the second TDRS generation, launched in August 2017, extending the life of the TDRS constellation beyond 2030.
|Sextant X-Ray Pulsar Navigation Demonstration: Initial On-Orbit Results|
Jason W. Mitchell, Luke B. Winternitz, Munther A. Hassouneh, Samuel R. Price, Sean R. Semper, Wayne H. Yu, Paul S. Ray, Michael T. Wolf, Matthew Kerr, Kent S. Wood
Millisecond pulsars (MSPs) are rapidly rotating neutron stars that appear to pulsate across the electromagnetic spectrum. Some MSPs have long-term timing stability that rivals that of atomic clocks. Pulse arrival phase can be predicted with great accuracy at any reference point in the Solar System through use of a pulsar timing model on a spacecraft.
|Exploring the Limits of High-Altitude GPS for Future Lunar Missions|
Benjamin W. Ashman, Joel J. K. Parker, Frank H. Bauer, Michael Esswein
An increasing number of spacecraft are relying on the Global Positioning System (GPS) for navigation at altitudes near or above the GPS constellation itself - the region known as the Space Service Volume (SSV).
|Options and Uncertainties in Planetary Defense: Mission Planning and Vehicle Design for Flexible Response|
Brent W. Barbee, Megan Bruck Syal, David Dearborn, Kevin Greenaugh, Kirsten M. Howley, Ron Leung, Josh Lyzhoft, Paul L. Miller, Joseph A. Nuth, Catherine Plesko, Bernard D. Seery, Joseph Wasem, Robert P. Weaver, Melak Zebenay
This paper is part of an integrated study by NASA and the NNSA to quantitatively understand the response timeframe should a threatening Earth-impacting near-Earth object (NEO) be identified. The two realistic responses considered are the use of a spacecraft functioning as either a kinetic impactor or a nuclear explosive carrier to deflect the approaching NEO.
|Latest Changes to NASA's Laser Communication Relay Demonstration Project|
Bernard L. Edwards, David J. Israel, Seema K. Vithlani
Over the last couple of years, NASA has been making changes to the Laser Communications Relay Demonstration Project (LCRD), a joint project between NASA's Goddard Space Flight Center (GSFC), the Jet Propulsion Laboratory, California Institute of Technology (JPL), and the Massachusetts Institute of Technology Lincoln Laboratory (MIT/LL).
|An Evaluation of Terrestrial Wireless Network Modeling Approaches for the Space Mobile Network|
Todd A. Newton, Christopher J. Roberts, Gregory G. Fletcher, Daniel S. Rossiter
The Space Mobile Network (SMN) is NASA’s next generation architecture concept for communications services between ground and space-based assets. The SMN calls for a paradigm shift in space communications.
|Low-latency teleoperations, planetary protection, and astrobiology|
Mark L. Lupisella, Margaret S. Race
The remote operation of an asset with time-delays short enough to allow for ‘real-time’ or near real-time control – often referred to as low-latency teleoperations (LLT) – has important potential to address planetary protection concerns and to enhance astrobiology exploration.
|Payload Performance of TDRS KL and Future Services|
Marco A. Toral, Gregory W. Heckler, Patricia M. Pogorelc, Nicholas E. George, Katherine S. Han
NASA has accepted two of the 3nd generation Tracking and Data Relay Satellites, TDRS K, L, and M, designed and built by Boeing Defense, Space Security (DSS). TDRS K, L, and M provide S-band Multiple Access (MA) service and S-band, Ku-band and Ka-band Single Access (SA) services to near Earth orbiting satellites.
|Preliminary Results from a Model-Driven Architecture Methodology for Development of an Event-Driven Space Communications Service Concept|
Christopher J. Roberts, Robert M. Morgenstern, David J. Israel, John M. Borky, Thomas H. Bradley
NASA's next generation space communications network will involve dynamic and autonomous services analogous to services provided by current terrestrial wireless networks. This architecture concept, known as the Space Mobile Network (SMN), is enabled by several technologies now in development.
|The Laser Communications Relay Demonstration Experiment Program|
David J. Israel, Bernard L. Edwards, John D. Moores, Sabino Piazzolla, Scott Merritt
This paper elaborates on the Laser Communications Relay Demonstration (LCRD) Experiment Program, which will engage in a number of pre-determined experiments and also call upon a wide variety of experimenters to test new laser communications technology and techniques, and to gather valuable data.