ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / This paper discusses the effect of vehicle exhaust plasma/plume on the ability to receive telemetered data via an S-band RF link. The data presented herein were captured during the launch of the STARS FT-04-1 on February 23, 2006 from Kodiak Launch Center, Kodiak, Alaska using Alaska Aerospace Development Corporation’s (AADC) Range Safety and Telemetry System (RSTS), designed and integrated by Honeywell.

ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper discusses the effect of vehicle exhaust plasma/plume on the ability to receive telemetered data via an S-band RF link. The data discussed herein was captured during the launch of the STARS IFT-14 on February 13, 2005 from Kodiak Launch Center, Kodiak, Alaska using Alaska Aerospace Development Corporation’s (AADC) Range Safety and Telemetry System (RSTS), designed and integrated by Honeywell.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / This paper presents the interim results of an effort to corroborate analytic model predictions of the effects of rocket motor plume on telemetry signal RF propagation. When space is available, telemetry receiving stations are purposely positioned to be outside the region of a rocket motor's plume interaction with the RF path; therefore, little historical data has been available to corroborate model predictions for specific rocket motor types and altitudes. RF signal strength data was collected during the flight of HERA target missile by White Sands Missile Range (WSMR) using a transportable telemetry receiving site specifically positioned to be within the rocket plume region of influence at intermediate altitudes. The collected data was analyzed and compared to an RF plume attenuation model developed for pre-mission predictions. This work was directed by the US Army Kwajalein Atoll (USAKA)/ Kwajalein Missile Range (KMR) Safety Division.

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / This paper discusses the effect of vehicle exhaust plasma/plume on the ability to receive telemetered data via an S-band RF link. The data discussed herein was captured during the launch of the QRLV-2 (Quick Reaction Launch Vehicle) on April 24, 2002 from Kodiak Launch Center, Kodiak, Alaska using Honeywell’s BMRST (Ballistic Missile Range Safety Technology) system.

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / A Wireless Local Area Network (WLAN) based system called 2-Way Robust Acquisition of Data (2-RAD) is being developed to telemeter data from a number of fast moving airborne platforms to ground collection points distributed over a large test range. The Johns Hopkins University Applied Physics Laboratory (JHU/APL) is analyzing a 2-RAD prototype currently in operation at the U.S. Army Yuma Proving Ground (YPG) that uses an IEEE 802.11b WLAN infrastructure. Preliminary analysis efforts at JHU/APL indicate that the Doppler shift from fast movers, and the system radio link margin, do not preclude IEEE 802.11b from being used for 2 -RAD.

10 Gigabit Ethernet (GbE) demands faster optical sources to support high modulation rates. At the same time, the allowable margin in the 10 GbE link power budget is decreasing. This means that a 10 GbE system is unable to support as many tight bends, and it is more difficult to avoid the costly downtime that results when the allowable margin is exceeded. The recent introduction of bend-optimized (BO) multimode fiber (MMF) provides a clear solution. 850 nm vertical cavity surface emitting lasers (VCSELs) and MMFs have long been the most cost effective choice for short reach premise applications. As will be shown, the combination of BO-MMF with VCSELs is even more attractive.Historically, MMF systems operating at low bit rates of 10-100 Mbps used light-emitting diodes (LED) sources, which launch nearly equal power into every fibermode. This launch is approximated by the overfilled launch (OFL), which is still used to characterize the core diameter and numerical aperture of MMF. Unlike LEDs, VCSELs typically underfill the fiber core and are better represented by an encircled flux launch (EFL). Using OFL to evaluate a VCSEL-based MMF system could therefore produce inaccurate and misleading results. A recent study [1] characterized the macrobend loss of MMF with overfilled and restricted mode offset launch conditions. In this study, the MMFs performance with an EFL is evaluated, which is a more relevant launch condition for laser transmission. The impact of both launch conditions, OFL and EFL, on MMF performance is studied and compared.We characterize macrobend losses at small bend radii and their impact on thebandwidth for both standard 50/125 um MMF and a newly introduced BO-MMF.In addition, the 10 GbE link performance is also evaluated using the IEEE link model P802.3ae3.The simulation results illustrate that both macrobend loss and bandwidth are vital to the overall optical link performance. The 10 GbE link performance of the standard fiber deteriorates with macrobends, while the bend-optimized fiber is insensitive to the deployment conditions.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper is a follow up to a paper presented at ITC 2002 entitled “Wireless Local Area Network for Data Telemetry from Fast Moving Nodes” by R. J. Bamberger, G. R. Barrett, R. A. Nichols, and J. L. Burbank of the Johns Hopkins University Applied Physics Laboratory, and M. H. Lauss of the Yuma Test Center at the U.S. Army Yuma Proving Ground (YPG). In that paper, network-centric data telemetry systems, specifically those based on commercial off- the-shelf (COTS) technologies such as the IEEE 802.11b Wireless Local Area Network (WLAN), were offered as an improvement over traditional frequency modulated (FM) data telemetry systems. The feasibility study of using WLANs for data telemetry considered both the radio frequency (RF) link over extended ranges and the effect due to Doppler shift. This paper describes an experiment designed to test those previous analyses.

International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / In support of the X-33 single-stage-to-orbit program, NASA Dryden Flight Research Center was selected to provide continuous range communications of the X-33 vehicle from launch at Edwards Air Force Base, California, through landing at Malmstrom Air Force Base, Montana, or at Michael Army Air Field, Utah. An extensive real-time range simulation capability is being developed to ensure successful communications with the autonomous X-33 vehicle. This paper provides an overview of the various levels of simulation, integration, and test being developed to support the X-33 extended range subsystems. These subsystems include the flight termination system, L-band command uplink subsystem, and S-band telemetry downlink subsystem.

By placing millions of space sunshades, of the order of 104 m2 at the sub-Lagrangian point L1',between the sun and Earth, solar radiation can be reduced enough to achieve the necessary temper-ature reduction to enable a slow down of the global warming. The vast amount of space sunshadesposes significant challenges on the communication system, as the probability of interference, whichcan distort information, increases with the number of simultaneously communicating units.This thesis aims to design a potential structure for the communication system that minimizesinterference as much as possible. To reduce the number of simultaneously communicating units, thesunshades are arranged in cell formation, where a mother is placed in the center with daughtersaround that only communicate with their specific cell mother. Direct communication betweenthe Earth and space sunshades is not possible as the interference from solar radiation can causesignificant distortion on the signals. Therefore, relay satellites are placed in orbit around thesub-Lagrangian point L1' at a sufficient distance to avoid the effects of solar radiation. Thus, thecommunication between the mothers and Earth is instead routed via the relay satellites. Sincecommunication between such a large number of entities in space has not been investigated before,this approach could provide a possible basic design framework for designing such infrastructure inthe future.