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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Advanced Range Telemetry (ARTM) Systems Integration at Edwards AFB

Briggs, James R. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / This paper describes the integration effort of ARTM systems into the existing telemetry infrastructure at the Air Force Flight Test Center (AFFTC) at Edwards AFB, California. This paper will also discuss the framework of the ARTM integration effort, which includes defining user requirements, integration approach, management approach, procurement, test and evaluation, and coordination with the ARTM Joint Program Office (JPO). Interoperability with existing equipment and with other ranges will also be discussed. ARTM is a Central Test and Evaluation Investment Program (CTEIP) under the Office of the Secretary of Defense, Undersecretary for Acquisition and Technology whose purpose is to improve the efficiency of spectrum usage. As the ARTM program approaches completion, integration efforts are underway to take advantage of the capabilities developed by the ARTM program. This integration effort brings the Test and Evaluation (T&E) community at Edwards AFB a step closer to realizing solutions to a variety of telemetering challenges including the shrinking frequency spectrum, demand for higher data rates, and the need to maintain the current level of commonality and interoperability between Major Range and Test Facility Bases (MRTFB).
2

Advanced Range Telemetry (ARTM) Systems Integration at the Air Force Flight Test Center

Briggs, James R. 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The aeronautical telemetry frequency spectrum is continually shrinking. More and more government frequencies are being sold to telecommunications companies. To make matters worse, more complicated weapons systems are spurring the demand for higher data rates. The telemetry infrastructure is struggling to meet these demands as the equipment continues to age and is, in some cases, no longer supported by the manufacturer. The loss of portions of the aeronautical frequency spectrum has had significant effects at Edwards. Increasing scheduling conflicts and mission cancellations are rapidly becoming a fact of life. This paper describes the scope of the Advanced Range Telemetry Integration and Support (ARTM I&S) program as it begins to integrate ARTM-developed products into the existing telemetry infrastructure at the Air Force Flight Test Center (AFFTC). This paper will discuss the infrastructure upgrades required in order to continue supporting test and evaluation missions. Numerous challenges will be addressed including the shrinking aeronautical frequency spectrum, aging telemetry infrastructure, and the demand for higher data rates. Possible solutions will be discussed to address the growing spectrum encroachment issue.
3

ARTM CHANNEL SOUNDING RESULTS – AN INVESTIGATION OF FREQUENCY SELECTIVE FADING ON AERONAUTICAL TELEMETRY CHANNELS

Rice, Michael, de Gaston, David, Davis, Adam, German, Gus, Bettwieser, Christian 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Initial results of wideband channel sounding experiments sponsored by the Advanced Range Telemetry (ARTM) program are presented. Data collected at Edwards EAFB during the Winter 1998-1999, are analyzed in the frequency domain to estimate the number, strength, and delays of the significant multipath reflections observed during the experiments. We observe that the channel is adequately modeled using two or three multipath reflections. The multipath fade events are correlated with recorded bit error rates and transmitter location to provide a comprehensive overview of the channel characteristics. Summaries from two test flights are included where it is seen that the 2- and 3-ray channel models provide excellent models for the data. In general, the 3-ray model captures the essential features of the multipath interference. In this model the first multipath is a strong specular reflection with relative amplitude greater than 0.5 and relative delay in the 30 to 70 ns range. The second multipath is a much weaker reflection with relative amplitude less than 0.5 and relative delay in the 175 to 325 ns range.
4

THE EFFECTS OF CARRIER FREQUENCY AND ANTENNA DIAMETER ON FREQUENCY SELECTIVE MULTIPATH FADING

Paje, Vladimir I. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / This paper uses ARTM channel sounding data collected at Edwards Air Force Base to investigate the dependency between the characteristics of frequency selective multipath fading and carrier frequency and ground based received antenna diameter. Channel model parameters are obtained from data sets measured at different frequencies and various ground based antenna diameters. The analysis shows that the multipath characteristics do not statistically change between the L-band and S-band carrier frequencies, but do change with antenna diameter. Furthermore, Flight 18 data shows that antenna diversity may be a useful technique to reduce data loss from multipath fading.
5

ARTM CPM Receiver/Demodulator Performance: An Update

Temple, Kip 10 1900 (has links)
ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / Since the waveform was first developed by the Advanced Range Telemetry Program (ARTM) and adopted by the Range Commanders Council Telemetry Group (RCC/TG), receiver/demodulators for the ARTM Continuous Phase Modulation (CPM) waveform have undergone continued development by several hardware vendors to boost performance in terms of phase noise, detection performance, and resynchronization time. These same results were initially presented at the International Telemetry Conference (ITC) 2003 when hardware first became available supporting this waveform, at the time called ARTM Tier II. This paper reexamines the current state of the art performance of ARTM CPM receiver/demodulators available in the marketplace today.
6

NETWORK CONNECTIONS BEYOND IEEE 802.11

Zettwoch, Robert N. 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / More and more aircraft system designs are incorporating a local-area-network (LAN) using either Fibre Channel (FC) or Ethernet. To date there hasn’t been a means for creating a FC node connection between an airborne network and a ground based FC network or for creating a reliable high-speed Ethernet connection between air and ground. Ethernet connections have had some success by using the IEEE 802.11 wireless LAN for these types of connections; however, these connections suffer from many inherent problems using this standard. Problems include the lack of telemetry spectrum control, security validation, high-speed data transfer efficiency, and channel acquisition time. This paper will describe a methodology that utilizes the IRIG-106 PCM standard for communicating between aircraft and ground-based networks. PCM can solve the aforementioned problems and it enables the user to take advantage of the many ARTM advances in PCM telemetry technology [1]. One such advance in technology has been the use of SOQPSK (Tier 1) or Multi-h CPM (Tier 2) to enable the user to effectively double or more their bandwidth efficiency compared to PCM/FM (or CPFSK) (Tier 0).
7

Towards a Low Complexity Implementation of a Multi-H CPM Demodulator

Guéguen, Arnaud, Auvray, David 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Multi-h Continuous Phase Modulation (CPM) is a promising waveform for aeronautical telemetry because it is a compact spectrally efficient constant amplitude modulation. It has been selected as the Advanced Range Telemetry (ARTM) tier II waveform owing to these qualities. However, it is also a complicated waveform that has the reputation of suffering from complex demodulation processing and high sensitivity to transmission impairments and in particular synchronization aspects. In this paper we review a set of complexity reduction techniques that intend to bring this waveform into the domain of operational telemetry waveform, by allowing low complexity hardware implementation without sacrificing performance or robustness. Most techniques are adjustments of recent literature results, concerning both demodulation and synchronization. Computer simulation of a receiver implementing theses techniques shows negligible performance loss compared to optimal coherent demodulation with perfect synchronization. Hardware implementation confirms that nearly optimal performance can be achieved with hardware resource currently available in middle range FPGAs.
8

DOPPLER BANDWIDTH CHARACTERIZATION OF ARTM CHANNEL SOUNDING DATA

Landon, David 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Data from ARTM channel sounding test flights is examined to characterize the dynamic channel behavior of aeronautical telemetry channels. The dynamic behavior is characterized using the Doppler power spectrum. The width of the Doppler power spectrum is the Doppler bandwidth of the channel which indicates the required bandwidth of adaptive detection techniques such as adaptive equalization, adaptive modulation, adaptive channel selection and adaptive error control coding. Data collected from ARTM Flight 11 suggest a Doppler bandwidth exceeding 6.7 Hz for the channel, but greater accuracy and resolution will only be possible with more data.
9

BIT ERROR PERFORMANCE ANALYSIS OF BPSK IN THE PRESENCE OF MULTIPATH FADING

de Gaston, David E. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The presence of multipath fading has been shown to degrade the performance of a wireless channel. This paper quantifies the effects of multipath interference on signal performance based on the estimated parameters of the multipath signal. Theoretical results are compared with actual results obtained through the Advanced Range Telemetry (ARTM) program.
10

DYNAMIC BEHAVIOR OF MULTIPATH INTERFERENCE IN ARTM CHANNEL SOUNDING DATA

Davis, Adam Todd 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Data collected during July 1999 at Edwards EAFB by the Advanced Range Telemetry (ARTM) program is examined to characterize the dynamic behavior of multipath interference in an aeronautical telemetry channel. Multipath fade events are analyzed in the frequency domain to show how these fades appear, evolve, and disappear from the channel. A channel model and examples from the channel sounding data are used to show the dynamic nature of these fade events. The Doppler power spectrum is used to quantify the exact time-varying nature of the multipath fade events. The coherence time, or the amount of time the channel can be viewed as unchanging, is obtained from the Doppler power spectrum and is calculated to be 100 ms in the data sets examined in this paper. This implies that adaptive multipath mitigation techniques must have an adaptation bandwidth of 10 Hz.

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