• Isually Lossless Coding for Color Aerial Images Using PEG

      Marcellin, Michael W.; Bilgin, Ali; Oh, Han; Kim, Yookyung; University of Arizona (International Foundation for Telemetering, 2009-10)
      This paper describes a psychophysical experiment to measure visibility thresholds (VT) for quantization distortion in JPEG2000 and an associated quantization algorithm for visually lossless coding of color aerial images. The visibility thresholds are obtained from a quantization distortion model based on the statistical characteristics of wavelet coefficients and the deadzone quantizer of JPEG2000, and the resulting visibility thresholds are presented for the luminance component (Y) and two chrominance components (Cb and Cr). Using the thresholds, we have achieved visually lossless coding for 24-bit color aerial images at an average bitrate of 4.17 bits/pixels, which is approximately 30% of the bitrate required for numerically lossless coding.
    • Key Components of the iNET Test Article Standard

      Grace, Thomas B.; Kenney, Joshua D.; Moodie, Myron L.; Abbott, Ben A.; Naval Air Systems Command (NAVAIR) (International Foundation for Telemetering, 2009-10)
      The integrated Network-Enhanced Telemetry (iNET) Test Article Standards Working Group (TASWG) has developed a standard for Telemetry Network System (TmNS). The introduction of Internet Protocol (IP) networks on test ranges has created the potential for greater flexibility in the telemetry environment. This paper discusses the rationale for particular decisions concerning key components mandated by the standard. Performance implications concerning the mandates of the standard are also described. As an educational aid, examples of TAS-based processing philosophies and data structures have been constructed. These examples, including sending and receiving messages, are shown to reinforce understanding core concepts of the standard.
    • Look Ma, No Hardware!

      Guadiana, Juan M.; White Sands Missile Range (International Foundation for Telemetering, 2009-10)
      Google Soft Decom and the number of hits will be tenfold over the same search last year. The migration of hardware functionality toward software is relentless. On the telemetry front, Data Bridges that take Pulse Code Modulated (PCM) signals and transform them to ubiquitous network packets make it all too easy. The need for expensive hardware such as the Decommutator (Decom), Frame Synchronizer, Digital Recorder, and Oscillograph Recorder (StripChart) will diminish sharply. Software Decom packages will feel the squeeze too, from homegrown Soft Decom software that is easier to maintain and has no licensing issues. This paper airs the dirty laundry associated with this hardware and software. Latencies and ugly temporal aberration that really plague an analyst. Also discussed is how a few packet/file formats eliminate the need for most of the hardware in a traditional telemetry data processing facility.
    • Low Noise Amplifiers with High Dynamic Range

      Ridgeway, Robert; Digi International (International Foundation for Telemetering, 2009-10)
      This new transistor will make it possible to achieve signal to noise ratio improvements of up to 15 dB (six times more link distance) for systems where the antenna looks sky ward. Using this type of low noise pHEMT device for on the horizon links insures that the telemetry link will be limited only by the natural thermal radio back ground noise and not by the receivers noise.
    • Low-Density Parity-Check Codes Which Can Correct Three Errors Under Iterative Decoding

      Vasic, Bane; Marcellin, Michael W.; Krishnan, Anantha Raman; Chilappagari, Shashi Kiran; University of Arizona (International Foundation for Telemetering, 2009-10)
      In this paper, we give necessary and sufficient conditions for low-density parity-check (LDPC) codes with column-weight four to correct three errors when decoded using hard-decision message-passing decoding. We then give a construction technique which results in codes satisfying these conditions. We also provide numerical assessment of code performance via simulation results.
    • Measuring and Evaluating Best Source Selection

      Corry, Diarmuid; ACRA Control Inc. (International Foundation for Telemetering, 2009-10)
      To properly evaluate and characterize the performance of a bit synchronizer we need to apply a known data stream and then adjust several interference parameters to measure the effect on synchronization performance: white noise, offset and gain variations and frequency and phase shifts. The task becomes more complex when we consider the performance of a best source selector (BSS) which combines the performance of two or more bit synchronizers to achieve better bit error rates and more consistent synchronization than can be achieved with one alone. Each of the parameters (noise, offset, gain, phase) are often different for each bit synchronizer, and may vary over time. In addition the incoming bit streams can drift in time (possibly 100s of bits) with respect to each other. This paper discusses how these parameters are measured, and looks in particular at the problem of evaluating a BSS. Results showing the performance that can be achieved when aligning and combining multiple streams are presented and discussed.
    • Metadata Description Language: The iNET Metadata Standard Language

      Moore, Michael S.; Price, Jeremy C.; Cormier, Andrew R.; Malatesta, William A.; Southwest Research Institute; Naval Air Systems Command (NAVAIR) (International Foundation for Telemetering, 2009-10)
      In order to help manage the complexity in designing and configuring network-based telemetry systems, and to promote interoperability between equipment from multiple vendors, the integrated Network-Enhanced Telemetry (iNET) Metadata Standards Working Group (MDSWG) has developed a standard language for describing and configuring these systems. This paper will provide the community with an overview of Metadata Description Language (MDL), and describe how MDL can support the description of the requirements, design choices, and the configuration of devices that make up the Telemetry Network System (TmNS). MDL, an eXtensible Markup Language (XML) based language that describes a TmNS from various aspects, is embodied by an XML schema along with additional rules and constraints. Example MDL instance documents will be presented to illustrate how MDL can be used to capture requirements, describe the design, and configure the equipment that makes up a TmNS. Various scenarios for how MDL can be used will be discussed.
    • A Method for Tracking the Accuracy of Channel Estimates in MIMO Receivers

      Kosbar, Kurt; Gupte, Abhishek; Missouri University of Science and Technology (International Foundation for Telemetering, 2009-10)
      Multiple input multiple output communication systems offer significant advantages, but only if the receiver has an accurate estimate of the channel state information (CSI). To obtain a CSI estimate, the transmitter must stop sending data, and instead send a training sequence. To maximize throughput, the time spent sending training data should be minimized. This paper describes a method which allows the receiver to track the accuracy of its CSI estimate, so that it can request new training data only when necessary.
    • A Model-Based Methodology for Managing T&E Metadata

      Hamilton, John; Fernandes, Ronald; Darr, Timothy; Graul, Michael; Jones, Charles; Weisenseel, Annette; Knowledge Based Systems, Inc.; Edwards Air Force Base (International Foundation for Telemetering, 2009-10)
      In this paper, we present a methodology for managing diverse sources of T&E metadata. Central to this methodology is the development of a T&E Metadata Reference Model, which serves as the standard model for T&E metadata types, their proper names, and their relationships to each other. We describe how this reference model can be mapped to a range's own T&E data and process models to provide a standardized view into each organization's custom metadata sources and procedures. Finally, we present an architecture that uses these models and mappings to support cross-system metadata management tasks and makes these capabilities accessible across the network through a single portal interface.
    • Multipath Mitigation for Aeronautical Telemetry with Multiple Antennas

      Saquib, M.; Williams, Ian E.; University of Texas at Dallas (International Foundation for Telemetering, 2009-10)
      Frequency selective multipath is a key performance limiter for aeronautical telemetry applications. Our research explores multipath mitigation techniques with ARTM Tier-1 waveforms using linear adaptive filters, multiple receive antennas and error-based best source selection. Single antenna adaptive equalization alone is unable to substantially improve performance under certain channel conditions. Analytical investigations demonstrate that nonlinear channel phase response is the principal cause of performance loss. In this adverse environment, spatial diversity with multiple receive antennas along with error-based best source selection are capable of improving bit error rate performance by 5dB for each additional antenna.
    • Network Telemetry Link Throughput Maximization Approaches

      Moodie, Myron L.; Newton, Todd A.; Abbott, Ben A.; Southwest Research Institute (International Foundation for Telemetering, 2009-10)
      The use of Ethernet and Internet Protocol (IP) networking technologies in flight test instrumentation and telemetry systems is rapidly increasing, driven by the ubiquity, scalability, and flexibility of networking technologies. Networks first made a positive impact in ground station infrastructure and have recently been emerging in test article data acquisition infrastructure in programs such as the A380, 787, P-8A, and Future Combat Systems. The next logical step is to provide a two-way network telemetry link to fully extend the flexibility of the network between the test articles and ground station. The United States Department of Defense (DoD) integrated Network-Enhanced Telemetry (iNET) program is currently working to build a standardized network telemetry link for exactly this purpose. When developing a network telemetry link, the limited availability of telemetry spectrum must be considered and thus it is critical to choose system-level approaches to maximize the throughput achieved from the link. This paper first presents the statistics of the network data that would typically use this link based on empirical data from current network-based flight test instrumentation systems. Several approaches to using a network telemetry link are then presented. Predicted achievable throughputs of each approach are presented that are derived from the statistics of the empirical test data. Based on this, the paper presents recommendations for building systems using network telemetry links.
    • Networked Flight Test Instrumentation Data Recording Solutions

      Cranley, Nikki; Corry, Diarmuid; ACRA Control, Inc. (International Foundation for Telemetering, 2009-10)
      An integral component of networked Flight Test Instrumentation (FTI) and Health and Usage Monitoring Systems (HUMS) is the networked Data Recorder. The high data rates achievable in networked data acquisition systems put increased demands on the recorder to support ever faster read and write rates. Key to the success of the networked recorder is the format in which the data is recorded. The data recording file format should be network-centric with a low processing overhead to support the recording demands. In this paper the popular file formats, Chapter 10 and the Packet CAPture (PCAP), that are used for recording networked FTI are analyzed and compared.
    • Obtaining an ATO for an iNET Operational Demonstration

      Hodack, David; Naval Air Systems Command (International Foundation for Telemetering, 2009-10)
      The integrated Network Enhanced Telemetry (iNET) project was launched to foster network enhanced instrumentation and telemetry. The program is currently implementing an operational demonstration. That will involve installing and using a network enhanced instrumentation system on a helicopter. This demonstration will be used as a learning exercise for the implementation of network technologies. This paper will give a brief description of the operational demonstration. Then it will explore the need for an Authority to Operate (ATO) and describe how one was obtained.
    • OFDM Performance on Aeronautical Channnels

      Dean, Richard; Kamirah, Daniel K.; Morgan State University (International Foundation for Telemetering, 2009-10)
      This paper provides an introduction to the Orthogonal Frequency Division Multiplexing (OFDM) scheme which has been proposed for future aeronautical telemetry applications. OFDM offers the potential for high data rates on radio channels with multipath such as aeronautical telemetry channels. This paper provides in introduction to OFDM and demonstrates how orthogonality is maintained over multipath channels by the introduction of a guard band and by the inclusion of a cyclic prefix. The simulation of OFDM in multipath is simulated and performance results are presented that show the degradation of this scheme on a multipath channel with and without the guard band and the cyclic prefix.
    • Pacific Ranges Interoperable Test & Evaluation Capabilities (PRITEC)

      Hermann, Scott A.; Wigent, Mark A.; Chavez, Tomas C.; PMRF; SAIC; CSC (International Foundation for Telemetering, 2009-10)
      The office of the Defense Test Resources Management Center (DTRMC) has developed two major programs to achieve Joint/Interoperable exercises between DoD test and training ranges. Joint Mission Environment Test Capability (JMETC) defines a LVC environment in which Joint operations take place, while the Test and Training Enabling Architecture (TENA) defines the communication within that environment. Putting these programs to everyday use has been a challenge for the ranges. The Pacific Missile Range Facility (PMRF) is executing the Central Test & Evaluation Investment Program (CTEIP) sponsored Pacific Ranges Interoperable Test & Evaluation Capabilities (PRITEC) project designed to develop a set of tools that will facilitate implementation of JMETC and TENA. This paper will discuss the PRITEC project in detail.
    • Performance Analysis of Reentry TDOA Positioning System

      Nan, Xie; Futang, Zhang; China Academy of Engineering Physics (International Foundation for Telemetering, 2009-10)
      In reentry measurement, we need to measure the track of reentry vehicle. For the speed of target is very high, it is difficult for traditional positioning system to capture and track the target. TDOA (time difference of arrival) positioning system is used in reentry measurement. The position of target is calculated by using time difference of arrival. This paper introduces the principle of reentry TDOA positioning system. The key technology is synchronization of ground stations' clocks. The implementation of clock synchronization using low-cost commercial GPS receiver is presented. The sources of errors in the existing telemetry system, corresponding precision and experimental results are presented. Some methods, which are used to improve the precision, are proposed at the end of this paper.
    • Performance and Disruption Tolerance of Transport Protocols for Airborne Telemetry Networks

      Sterbenz, James P. G.; Rohrer, Justin P.; University of Kansas (International Foundation for Telemetering, 2009-10)
      The airborne telemetry environment presents unique challenges to end-to-end communications due to the highly dynamic topology and time-varying connectivity of high-velocity wireless nodes. The AeroTP transport protocol uses multiple reliability modes to trade off end-to-end reliability and efficiency as appropriate for different categories of telemetry data. Based on the architecture previously presented, we have further developed the design of this protocol, as well as performing preliminary simulations of AeroTP using the ns-3 simulation platform. In this paper we present the operational modes of AeroTP in greater detail, as well as comparing the performance of TCP with the AeroTP domain-specific transport protocol.
    • Performance Comparison of OFDM and DSSS on Aeronautical Channels

      Cole-Rhodes, Arlene; Dean, Richard; Ehichioya, Daniel; Golriz, Arya; Morgan State University (International Foundation for Telemetering, 2009-10)
      This paper develops a performance framework for OFDM by contrasting its performance with Direct Sequence Spread Spectrum (DSSS) over aeronautical channels. Each of the OFDM and DSSS modulated simulations are put through the channel and compared on terms of signal to noise ratio (SNR) versus bit error rate. The simulation will show that DSSS will have better power efficiency on multipath channels because the rake receiver adds all multipath components to strengthen the receiver. By contrast OFDM with an equalizer will have better spectrum efficiency results where QAM modulation of multiple tones allows for high data rates in a limited bandwidth. This work develops a framework for contrasting the performance of the rake receiver and the equalizer for operation on multipath channels. By comparing these schemes on various channels the choice of OFDM for iNET can be clearly understood and evaluated.
    • The Performance Evaluation of an OFDM-Based iNET Transceiver

      Lu, Cheng; Roach, John; Teletronics Technology Corporation (International Foundation for Telemetering, 2009-10)
      The nXCVR-2000G transceiver is an 802.11a OFDM-based system undergoing performance studies that uses both simulation and laboratory tests. The multi-path channel model used in the simulation experiments is based on a telemetry multi-path channel model described in the iNET Telemetry Experimental Standard document. To date, the results using the simulation have been confirmed by outdoor laboratory tests. They show that multi-path has less impact on the OFDM performance when the channel spread is within a limit of 800ns; the same specified guard interval (GI) used by 802.11a. For example, with a channel spread of 144ns (τ1) and a reflection coefficient of -0.26dB (Γ1), the Error Vector Magnitude (EVM) is on the order of 2.5%. As the channel spread expands beyond the standard GI 800ns, the demodulated signal degrades. The performance penalty depends upon the channel spread factor and the total Signal to Interference plus Noise Ratio (SINR).
    • Performance of an OFDM-Based DVB-T System and its FPGA Implementation

      Yang, Luyu; Song, Peng; Song, Qingping; North China University of Technology (International Foundation for Telemetering, 2009-10)
      Orthogonal frequency division multiplexing (OFDM) is a new technique for data transmission. Conforming to the final draft of OFDM-based DVB-T (ETSI EN 300 744 V1.6.1), which is intended for digital terrestrial television broadcasting, a DVB-T baseband system is designed. The system performance is simulated in MATLAB using Simulink. Then it is implemented on Field Programmable Gate Array (FPGA) with the help of System Generator software. The result shows that OFDM is robust against multipath effect and convenient for implementation as well, thus owning a quite promising future.