• PCM to Ethernet: A Hybrid System Used to Certify the Next Generation of Data Transfer Technology

      de Souza, Luiz Fernando; Rios, Domingos Henrique Beolchi; Willis, Stephen; Embraer S. A.; Curtiss-Wright Controls Avionics & Electronics (International Foundation for Telemetering, 2012-10)
      The last few years has witnessed the adoption of Ethernet technology in an increasing number of FTI applications. This is a result of both the growing acceptance within the community of the application of the technology, the availability of suitable hardware and the desire for increased parameters/higher data rates that PCM is unable to accommodate. However, migrating from an existing PCM based networked system to Ethernet is not typically just a case of exchanging the necessary hardware. There can be a range of other issues that require addressing such as ensuring determinism and realizing previous investment in hardware - this paper highlights and discusses several of these. This paper presents a case study of an FTI application on the Embraer Legacy 500 where a hybrid PCM and Ethernet configuration was implemented. One reason for this configuration was that it was necessary to prove to the Brazilian Aeronautical Agency that the data acquired using an Ethernet system was as reliable as that acquired using PCM. An additional reason was that such a system was seen as a safe stepping stone to a full Ethernet system for programs in the near future which are planning to fully migrate to an Ethernet architecture.
    • PCM vs. Networking: Spectral Efficiency Wars - A Pragmatic View

      Araujo, Maria S.; Abbott, Ben A.; Southwest Research Institute (International Foundation for Telemetering, 2012-10)
      The expected efficiency of network-based telemetry systems vs. the tried and true PCM-based approaches is a debated topic. This paper chooses to use a lighthearted voice to pull the two sides of the "war" to a table of negotiation based on metrics. Ultimately, focusing on metrics that truly define efficiency is the key to understanding the varying points of view. A table of these metrics along with the "why and when" criteria for their use is presented based on historic mathematical information theory, true flight test data requirements, and lab analysis. With these metrics, the negotiation and reasonable compromises in the war may become clear. In other words, this paper attempts to provide a methodology that can be used by the community to aid in choosing the appropriate (or good enough) technologies for current and future telemetry testing demands.
    • Performance Evaluation of the AeroTP Protocol in Comparison to TCP NewReno, TCP Westwood, and SCPS-TP

      Nguyen, Truc Anh N.; Gangadhar, Siddharth; Umapathi, Greeshma; University of Kansas (International Foundation for Telemetering, 2012-10)
      Due to the unique characteristics of highly dynamic airborne telemetry environments, TCP when deployed in such networks suffers significant performance degradation. Given the limitations of TCP, the AeroTP opportunistic transport protocol with multiple reliability modes has been developed to specifically address the issues posed by telemetry networks. In our previous work, the different modes of AeroTP have been simulated and tested using the open source ns-3 network simulator. In this paper, we use ns-3 to evaluate the overall performance of AeroTP by comparing it with well-studied TCP variants: the widely-deployed TCP NewReno and TCP Westwood designed for wireless environments. Since space networks share many similar characteristics with telemetry environments, we also compare AeroTP with SCPS-TP.
    • Performance of Turbo Coded OFDM Modulation over an Aeronautical Channel

      Cole-Rhodes, Arlene; Dean, Richard; Moazzami, Farzad; Assegu, Wannaw; Fofanah, Ibrahim; Morgan State University (International Foundation for Telemetering, 2012-10)
      The main objectives of Integrated Network Enhanced Telemetry (iNET) are increased data rate and improved spectral efficiency. In this paper we propose the transmission scheme for the physical layer to be coded Quadrature Amplitude Modulation-Orthogonal Frequency Division Multiplexing (QAM OFDM) which enables high data rates and spectrum efficiency. However in high mobility scenarios, the channel is time-varying the receiver design is more challenging. In this paper pilot-assisted channel estimation is used at the receiver, with turbo coding to enhance the performance; while the effect of inter symbol interference (ISI) is mitigated by cyclic prefix. The focus of this paper is to evaluate the performance of OFDM with QAM over an aeronautical channel. The M-QAM with OFDM provides a higher data rate than QPSK hence it is chosen in this paper. The implementation is done using Inverse Fast Fourier Transform (IFFT) and the Fast Fourier Transform (FFT). This paper considers how the performance of Coded QAM OFDM can be enhanced using equalization to compensate for inter symbol interference, and using turbo coding for error correction.
    • Positional Awareness Map 3D (PAM3D)

      Hoffman, Monica; Allen, Earl; Yount, John; Norcross, April; NASA Dryden Flight Research Center; Arcata Associates, Incorporated (International Foundation for Telemetering, 2012-10)
      The Western Aeronautical Test Range of the National Aeronautics and Space Administration's Dryden Flight Research Center needed to address the aging software and hardware of its current situational awareness display application, the Global Real-Time Interactive Map (GRIM). GRIM was initially developed in the late 1980s and executes on older PC architectures using a Linux operating system that is no longer supported. Additionally, the software is difficult to maintain due to its complexity and loss of developer knowledge. It was decided that a replacement application must be developed or acquired in the near future. The replacement must provide the functionality of the original system, the ability to monitor test flight vehicles in real-time, and add improvements such as high resolution imagery and true 3-dimensional capability. This paper will discuss the process of determining the best approach to replace GRIM, and the functionality and capabilities of the first release of the Positional Awareness Map 3D.
    • The Process of Implementing a RF Front-End Transceiver for NASA's Space Network

      Thompson, Willie L., II; Wilder, Ali; Pannu, Randeep; Haj-Omar, Amr; Morgan State University (International Foundation for Telemetering, 2012-10)
      Software defined radio (SDR) introduces endless possibilities for future communication technologies. Instead of being limited to a static segment of the radio spectrum, SDR allows RF front-ends to be more flexible by using digital signal processing (DSP) and cognitive techniques to integrate adaptive hardware with dynamic software. We present the design and implementation of an innovative RF front-end transceiver architecture for application into a SDR test-bed platform. System-level requirements were extracted from the Space Network User Guide (SNUG). Initial system characterization demonstrated image leakage due to poor filtering and mixer isolation issues. Hence, the RF front-end design was re-implemented using the Weaver architecture for improved image rejection performance.
    • Quasi-Orthogonal Frequency Division Multiple-Access for Serial Streaming Telemetry

      Ponnaluri, Satya Prakash; Azimi-Sadjadi, Babak; Intelligent Automation Inc. (International Foundation for Telemetering, 2012-10)
      We propose a spectrally-efficient multiple-access technique that is particularly suitable for aeronautical telemetry applications involving serial streaming of data from multiple test articles to a ground station. Unlike conventional frequency-division multiple access, we assign overlapping frequency bands to different users with a minimum carrier separation corresponding to the symbol rate. We utilize multiuser detection strategies at the ground station to separate the transmissions from different test articles. As shown by the simulation results, the proposed scheme is robust to large frequency offsets due to oscillator offsets and Doppler shifts commonly encounters in aeronautical telemetry applications.
    • Relying on Telemetry for Mission Critical Decisions: Lessons Learned from NASA's Reusable Launch Vehicle for Use on the Air Force's Next Generation Reusable Launch Vehicle

      Losik, Len; Failure Analysis (International Foundation for Telemetering, 2012-10)
      The U.S. Air Force's next generation reusable booster (NGRSB) offers the opportunity for the Space Command to use intelligent equipment for decision making replacing personnel, increasing safety and mission assurance by removing decisions from program management personnel who may not have had any flight-test experience. Adding intelligence to launch vehicle and spacecraft equipment may include requiring the builder to use a prognostic and health management (PHM) program. The PHM was added to NASA's aircraft programs in 2009 and we have requested NASA HQ and NASA Marshal Space Flight Center adopt the NASA PHM in the procurement contracts used on the new Space Launch Systems, NASA's congressionally mandated replacement for the Space Shuttle. Space Vehicle Program managers often make decisions for on-orbit spacecraft without ever having on-orbit space flight experience. Intelligent equipment would have eliminated the catastrophic failures on the NASA Space Shuttle Challenger and Columbia. These accidents occurred due to the lack of space vehicle subsystem engineering personnel analyzing real-time equipment telemetry presented on strip chart and video data prior to lift off during pre-launch checkout for the Space Shuttle Challenger and the lack of space vehicle real-time equipment telemetry for Columbia. The PHM requires all equipment to include analog telemetry for measuring the equipment performance and usable life determination in real-time and a prognostic analysis completed manually will identify the equipment that will fail prematurely for replacement before launch preventing catastrophic equipment failures that may cause loss of life.
    • Remote-Sensed LIDAR Using Random Impulsive Scans

      Creusere, Charles D.; Castorena, Juan; New Mexico State University (International Foundation for Telemetering, 2012-10)
      Third generation full-waveform (FW) LIDAR systems image an entire scene by emitting laser pulses in particular directions and measuring the echoes. Each of these echoes provides range measurements about the objects intercepted by the laser pulse along a specified direction. By scanning through a specified region using a series of emitted pulses and observing their echoes, connected 1D profiles of 3D scenes can be readily obtained. This extra information has proven helpful in providing additional insight into the scene structure which can be used to construct effective characterizations and classifications. Unfortunately, massive amounts of data are typically collected which impose storage, processing and transmission limitations. To address these problems, a number of compression approaches have been developed in the literature. These, however, generally require the initial acquisition of large amounts of data only to later discard most of it by exploiting redundancies, thus sampling inefficiently. Based on this, our main goal is to apply efficient and effective LIDAR sampling schemes that achieve acceptable reconstruction quality of the 3D scenes. To achieve this goal, we propose on using compressive sampling by emitting pulses only into random locations within the scene and collecting only the corresponding returned FW signals. Under this framework, the number of emissions would typically be much smaller than what traditional LIDAR systems require. Application of this requires, however, that scenes contain many degrees of freedom. Fortunately, such a requirement is satisfied in most natural and man-made scenes. Here, we propose to use a measure of rank as the measure of degrees of freedom. To recover the connected 1D profiles of the 3D scene, matrix completion is applied to the tensor slices. In this paper, we test our approach by showing that recovery of compressively sampled 1D profiles of actual 3D scenes is possible using only a subset of measurements.
    • Resolution Analysis and System Integration of a Dynamically Reconfigurable FMCW Medical Ultrasound Imaging System

      Liebling, Michael; Lee, Hua; Lee, Michael; Doonan, Daniel; University of California, Santa Barbara (International Foundation for Telemetering, 2012-10)
      This paper describes the system performance analysis of the dynamically reconfigurable FMCW medical ultrasound imaging systems. Full-scale resolution analysis, for mono-static, bi-static, and multi-static data-acquisition formats, and laboratory experiment are included in the analysis.
    • A Runlength Coded LDPC Scheme for Insertion/Deletion Correction in Multimedia Watermarking

      Vasic, Bata; Vasic, Bane; University of Nis; University of Arizona (International Foundation for Telemetering, 2012-10)
      We describe a simple and effective coding scheme for insertion/deletion channels. It is based on runlength coding which converts a class of insertion/deletion channels that have infinite memory into memoryless channels, which are much easier to handle. Runlength coding is then combined with powerful error correction low-density parity-check (LDPC) codes designed for memoryless channels. We consider a novel applications of this technique in multimedia watermarking using quantization index modulation operating on the three dimensional mesh vertices. The runlength LDPC coding recovers the data hidden in the vertices removed by the process of mesh simplification.
    • Servo Controls for Low S/N Satellite Auto-Tracking

      Busch, Chuck E.; ViaSat Inc. (International Foundation for Telemetering, 2012-10)
      At very low Signal to Noise receive ratios, a typical Autotrack servo loop exhibits significant servo noise tracking jitter that can degrade the received signal characteristics. The angular jitter can be minimized by a lowering of the autotracking servo loop bandwidth, but at the sacrifice of the servos ability to reject external torque disturbances, such as wind deflections. As satellite downlinks continue to move to higher frequencies, the angular errors caused by either the tracking noise or the wind deflections of a receive antenna will have increasingly negative effect on the quality of the received data. This paper examines the performance of a servo algorithm that maintains the needed wide bandwidth characteristics of wind deflection rejection while achieving the noise smoothing characteristics of a very low bandwidth Autotrack servo response. The control algorithms have been tested on a 13 meter Remote Sensing Satellite tracking system to determine the overall tracking performance of the new implementation. Current results indicate that the new servo configuration achieves the desired results typical of a wide bandwidth system of high wind rejection and low target dynamics tracking errors. At the same time, it provides elimination of slowly changing errors from axis miss-alignments, thermal effects, and gravitational effects and the low RF noise jitter performance typical of a low bandwidth system.
    • Small Wearable Antenna for Animal Tracking

      Melde, Kathleen; Marcellin, Michael; Fowler, Jared R.; Austin, Jon M.; Estrada, Kathy T.; Velazquez, Martin; Mohr, Robyn; Sanchez, Ruben; University of Arizona (International Foundation for Telemetering, 2012-10)
      Many tracking devices exist in today's world. There are car tracking devices, hunting dog tracking devices, and even cell phone tracking devices. The use of Global Positioning Systems (GPS) has increased the ability to track various subjects throughout all parts of the world. However, there is no reliable tracking device for small mammals that allows researchers to maintain an unobtrusive distance from the animals. The goal of this project was to begin the process for designing a tracking system for small mammals. The overall system design utilizes a Garmin Astro 320 GPS tracking unit in order to focus on effectively reducing the size of the external antenna. Through the use of current technology and the knowledge of several engineering disciplines, an antenna was designed and embedded into a collar which connects with the Astro unit. This new antenna is compact and more suitable for tracking the Golden Lion Tamarin, a small monkey living in the Brazilian rain forest.
    • The Space Ground Link Subsystem (SGLS) Downlink Detection Improvement

      Washburn, Greg; Corman, David; ITT Exelis (International Foundation for Telemetering, 2012-10)
      The Space Ground Link Subsystem (SGLS) downlink signals are a PM/PSK modulation and have been detected at VAFB by detuning the receivers to the subcarrier frequency or by using cascaded demodulators. A recent demodulator enhancement by SEMCO allows a single box solution by internally routing the signals between FPGAs. This paper discusses the test methods and compares the results of the legacy methods of demodulation with the new demodulators.
    • Spectrum Efficient Technology Today, Tomorrow and Beyond

      Young, Tom; Santiago, Mark; Radke, Mark; Edwards Air Force Base (International Foundation for Telemetering, 2012-10)
      In preparation for the onslaught of the commercial wireless appetite, we, the test community, must continually invest in methods to better utilize the Department of Defense (DoD) Radio Frequency (RF) spectrum allocations and or leverage the shared commercial space. There is an ever increasing demand for the limited physical allocations within the RF spectrum for wireless communications. This has never been more prevalent within the test community as it is today with the continuing encroachment of the commercial wireless communication systems. These commercial entities are investing billions of dollars to insure that the bandwidth demands of the public are met which in turn will affect the DoD allocations and usage. Based on the need for increasing data rates, number of simultaneous tests, number of test participants and competition from the commercial sector, the test community must continually improve our efficiency of use within the wireless communications space. To accomplish this, the Test Resource Management Center (TRMC) has identified a Test Technology Area (TTA) Spectrum Efficient Technology (SET) that targets methodologies to more efficiently and effectively utilize this wireless test asset. The SET team has broken down the problem space into three distinct domains; wireless technologies, telemetry networking, and spectrum management. The idea therein is to maximize efficiency within the legacy use of the RF spectrum, while improving the utilization of this constrained resource with technology investment. Much of this work requires leveraging commercial technologies/trends and applying these technologies to the dynamic test environment problem space.
    • Spectrum Management in Telemetry Networks

      Fofanah, Jemilatu; Morgan State University (International Foundation for Telemetering, 2012-10)
      Spectrum efficiency is the key challenge in modern telemetry systems. Network telemetry requires moving from a dedicated link structure to a network structure which is a very complex problem and requires spectrum management tools. A mixed network structure has been previously proposed for networked telemetry which employs a combination of cellular and Adhoc networks. Significant improvements in QoS and clustering of the complex aeronautical networks have been observed and published in several venues. However in the earlier work routing within the Ad-hoc clusters has not been addressed and the clustering has been done using an enhanced K-means clustering. In this paper, a well known clustering algorithm is adopted in the mixed network concept and clustering of the Ad-hoc nodes are optimized based on shortest route to the gateway and minimum hop count criteria. The proposed clustering technique in this paper leads to a jointly optimized cluster-topology and gateway-selection solution a complex aeronautical network. Simulation results towards the end of this paper illustrate that with the proposed method, cluster configuration is locally optimized and the best gateway for each cluster is successfully selected. With addition of traffic measures to the consideration in the routing, the proposed solution will leads to efficient spectrum allocation and improved QoS.
    • Spectrum Management Metrics Development

      Jones, Charles H.; Edwards Air Force Base (International Foundation for Telemetering, 2012-10)
      There is a lot of talk about there not being enough spectrum available for use by either government or industry. One would thus suppose that there are clear answers to the questions, "How much spectrum is being used?" and "How much spectrum would be used if it was available?" Unfortunately, clear answers do not exist. In fact, even if you collected data, analyzed it, and generated charts, there is likely to be (and, in fact, have been) long debates about the meaning of those charts. A fundamental problem is that there are no standard metrics for reporting spectrum usage. A well-defined and documented set of metrics would aid in any analysis and discussion of spectrum usage. The Range Commander's Council (RCC) Frequency Management Group (FMG) has initiated a formal Task, FM-37, to develop and standardize a set of spectrum management metrics. These metrics will go beyond simple usage and provide metrics for analysis of spectrum management in general, such as spectrum usage requirements, scheduling efficiencies, and prediction of impacts to spectrum availability. This paper overviews an initial draft of the document being developed under Task FM-37.
    • A Spectrum Management Tool to Aid Efficient Frequency Assignments at Test Ranges

      Madon, Phiroz H.; Gadgil, Shrirang; Harasty, Daniel J.; Kim, Heechang; Triolo, Anthony A.; Ziegler, Robert A.; Applied Communication Sciences (International Foundation for Telemetering, 2012-10)
      Increasing demands for telemetry bandwidth in conjunction with commercial encroachments on telemetry spectrum have created a need for test range operations personnel to make frequency assignments in the most efficient manner possible. The Spectrum Management System (SMS) project researches a potential tool to bring advanced capabilities to the assistance of test range operations. Features that appear to have significant utility are: frequency assignment optimizations to simultaneously satisfy device and spectrum constraints, prediction of RF channel quality across airspace, and support for frequency reuse. A prototype system is currently being trialed at selected test ranges.
    • Spectrum Savings from High Performance Network Recording and Playback Onboard the Test Article

      Wigent, Mark A.; Mazzario, Andrea M.; SAIC; Kauai Software Solutions (International Foundation for Telemetering, 2012-10)
      The Test Resource Management Center's (TRMC) Spectrum Efficient Technologies (SET) S&T program is sponsoring development of the Enhanced Query Data Recorder (EQDR), a network flight recorder that is intended to meet the future needs of the networked telemetry environment. EQDR is designed to support the "fetch" of recorded test data during a test without interrupting the ongoing recording of data from the test article vehicle network. The key benefits of the network data recorder as implemented in EQDR are increased flexibility and efficiency of test in an environment with increasing demands on spectrum available for telemetered data. EQDR enables retrieval of individual recorded parameters on an as-needed basis. Having the flexibility to send data only when it is required rather than throughout the duration of the test significantly increases the efficiency with which limited spectrum resources are used. EQDR enables parametric-level data retrieval, based not only on time interval and data source, but also on the content of the recorded data messages. EQDR enables selective, efficient retrieval of individual parameters using indexes derived from the actual values of recorded data. This paper describes the design of EQDR and the benefits of selective data storage and retrieval in the application of networked telemetry. In addition it describes the performance of the EQDR in terms of data recording and data retrieval rates when implemented on single board computers designed for use in the aeronautical test environment with size, weight, and power constraints.
    • Standardization of the Instrumentation Hardware Abstraction Language in IRIG 106

      Hamilton, John; Fernandes, Ronald; Darr, Timothy; Jones, Charles H.; Faulstich, Ray; Knowledge Based Systems, Inc.; Edwards Air Force Base; CSC Range and Engineering Services (International Foundation for Telemetering, 2012-10)
      Previously, we have presented an approach to achieving standards-based multi-vendor hardware configuration using the Instrumentation Hardware Abstraction Language (IHAL) and an associated Application Programming Interface (API) specification. In this paper we describe the current status of the IHAL standard. Since the first introduction of IHAL at ITC 2006, the language has undergone a number of additions and improvements. Currently, IHAL is nearing the end of a 2-year standardization task with the Range Commanders Council Telemetry Group (RCC TG). This paper describes the standardization process in addition to providing an overview of the current state of IHAL. The standard consists of two key components: (1) the IHAL language, and (2), the IHAL API specification.