NASA Scientific and Technical Aerospace Reports

20040068297 National Telecommunications and Information Administration, Washington, DC, USA
Proceedings of the International Symposium on Advanced Radio Technologies, March 2-4, 2004
Allen, J. W.; Brown, T. X.; Sicker, D. C.; Ratzloff, J.; Mar. 2004; In English
Report No.(s): PB2004-105434; NTIA-SP-04-409; No Copyright; Avail: National Technical Information Service (NTIS)
Contents: Accuracy Enhancements for TDOA Estimation on Highly Resource Constrained Mobile Platforms; Enhanced
Location Estimation via Pattern Matching and Motion Modeling; Mobile Transmitters Tracking Using Geodetic Models with
Multiple Receivers; IP Wireless Networks for Digital Video and Data Along Highway Right of Way; Local Spectrum
Sovereignty: An Inflection Point in Allocation; Channel Usage Classification Using Histogram-Based Algorithms for Fast
Wideband Scanners; Measurement and Analysis of Urban Spectrum Usage; Analog Front-End Cost Reduction for
Multi-Antenna Transmitter; Satellite Communications using Ultra Wideband (UWB) Signals; Spectrum Agile Radio:
Detecting Spectrum Opportunities; Alternative Communication Networking in Polar Regions; Signal Capacity Modeling for
Shared Radio System Planning; Rapidly Deployable Broadband Communications for Disaster Response; Trends in Telecom
Development Globally: A Perspective from Washington; Mesh Networks: The Next Generation of Wireless Communications;
Performance Analysis of Dynamic Source Routing Using Expanding Ring Search for Ad-Hoc Networks; Label-based
Multipath Routing (LMR) in Wireless Sensor Networks; Low Cost Broadband Wireless Access - Key Research Problems and
Business Scenarios.
NTIS
Spectra; Satellite Communication; Augmentation; Wireless Communication
20040070836 Integrated Systems Consultants, USA
TAXI Direct-to-Disk Interface Demultiplexes Proprietarily Formatted Data
Newnan, Bruce G.; Ahlport, Steven F.; [2001]; 1 pp.; In English; Original contains color illustrations
Report No.(s): NASA/NP-2001-10-00018-SSC; SSC-00141; No Copyright; Avail: CASI; A01, Hardcopy
The TAXI Direct-to-Disk interface is a special-purpose interface circuit for demultiplexing of data from a Racal Storeplex
(or equivalent) multichannel recorder onto one or more hard disks that reside in, and/or are controlled by, a personal computer
(PC). (The name TAXI as used here is derived from the acronym TAXI, which signifies transparent asynchronous transceiver
interface.) The TAXI Direct-to-Disk interface was developed for original use in capturing data from instrumentation on a test
stand in a NASA rocket-testing facility. The control, data-recording, and data-postprocessing equipment of the facility are
located in a control room at a safe distance from the test stand. Heretofore, the transfer of data from the instrumentation to
the postprocessing equipment has entailed post-test downloading via software, requiring many hours to days of post-test
reduction before the data could be viewed in a channelized format. The installation of the TAXI Direct-to-Disk interface, in
conjunction with other modifications, causes the transfer of data to take place in real time, so that the data are immediately
available for review during or after the test. The instrumentation is connected to the input terminals of the signal-processing
unit of multichannel recorder by standard coaxial cables. The coaxial output of the signal processing unit is converted to
fiber-optic output by means of a commercial coaxial-cable/fiber-optic converter (that is, a fiber-optic transceiver) designed
specifically for this application. The fiber-optic link carries the data signals to an identical fiber-optic transceiver in the control
room. On the way to the TAXI Direct-to-Disk interface that is the focus of this article, the data signals are processed through
a companion special purpose circuit denoted by the similar name parallel TAXI interface.
Author (revised)
Demultiplexing; Circuits; Data Transfer (Computers); Interfaces; Transmitter Receivers
20040073484 NASA Glenn Research Center, Cleveland, OH, USA
Evolutionary Space Communications Architectures for Human/Robotic Exploration and Science Missions
Bhasin, Kul; Hayden, Jeffrey L.; April 2004; 20 pp.; In English; Space Technology and Applications International Forum
(STAIF-2004), 8-12 Feb. 2004, Albuquerque, NM, USA
Report No.(s): NASA/TM-2004-213074; E-14550; No Copyright; Avail: CASI; A03, Hardcopy
NASA enterprises have growing needs for an advanced, integrated, communications infrastructure that will satisfy the
capabilities needed for multiple human, robotic and scientific missions beyond 2015. Furthermore, the reliable, multipoint
infrastructure is required to provide continuous, maximum coverage of areas of concentrated activities, such as around Earth
and in the vicinity of the Moon or Mars, with access made available on demand of the human or robotic user. As a first step,
the definitions of NASA’s future space communications and networking architectures are underway. Architectures that
describe the communications and networking needed between the nodal regions consisting of Earth, Moon, Lagrange points,
Mars, and the places of interest within the inner and outer solar system have been laid out. These architectures will need the
modular flexibility that must be included in the communication and networking technologies to enable the infrastructure to
71