• Performance Analysis of iNET Using Forward Error Correction and OFDM

      Dean, Richard A.; Cole-Rhodes, Arlene; Boru, Sileshi; Maitra, Diptasree; Morgan State University (International Foundation for Telemetering, 2010-10)
      This paper shows the improvement in performance for OFDM modulation on aeronautical channels with the addition of convolution coding. OFDM is envisioned for use on the Integrated Network Enhanced Telemetry (INET) on aeronautical channels that experience multipath fading which causes inter-symbol interference (ISI). Forward error correction coding, such as convolution coding (cc), significantly improves the bit error rate (BER) of OFDM with multipath fading. Theoretical and simulated results show a performance increase of up to 10dB with the introduction of coding gain and the cyclic prefix (cp). Such improvements can be applied to reduce errors or increase data rates for INET.
    • Performance Comparison of Aeronautical Telemetry in S-Band and C-Band

      Temple, Kip; Selbrede, Robert; Edwards Air Force Base (International Foundation for Telemetering, 2010-10)
      This paper compares telemetry link performance of the PCM/FM waveform when simultaneously transmitting in two different frequency bands, S-Band and C-Band. A description of the aircraft and ground station is presented followed by flight test results. These results are presented in the form of received signal strength and accumulated bit errors, versus time and link availability, over the flight paths. Conclusions are drawn based upon the presented flight test results.
    • Performance Evaluation of a TDMA MAC Protocol in Airborne Telemetry Networks

      Perrins, Erik; Sterbenz, James P. G.; Tunç, Muharrem Ali; University of Kansas (International Foundation for Telemetering, 2010-10)
      Emerging airborne telemetry networks are going beyond traditional point-to-point communication. The iNET telemetry architecture uses a TDMA MAC with relay nodes that enable multi-hop communication. We analyze the performance of the iNET TDMA MAC protocol with respect to various parameters such as number of nodes, flight range, number of relays, and number of hops via mathematical modeling. We also discuss the role of cross-layer optimizations with the AeroNP, AeroRP, and AeroTP aeronautical protocols.
    • The Performance Evaluation of an OFDM-Based IP Transceiver at Eglin AFB

      Berard, Alfredo; Cook, Paul; Roach, John; Eglin Air Force Base; Teletronics Technology Corporation (International Foundation for Telemetering, 2010-10)
      The 46th Test Wing, 846th Test Support Squadron (846 TSS/TSI) at Eglin AFB is currently evaluating their airspace for the use of SOQPSK transmitters and receivers for telemetry. The Squadron will incorporate an IP-compatible OFDM transceiver from Teletronics Technology Corporation (TTC) that will provide a two-way communication channel for controlling configuration settings of the airborne SOQPSK transmitter and receiver. This provides an opportunity to evaluate the effectiveness of an airborne network instrumentation system and measure some critical parameters, with an opportunity to assess the performance and reliability of streaming telemetry and OFDM-based IP communication systems. This paper describes the experimental test setup created for this evaluation and summarizes the measurement and evaluation process.
    • QoS Performance Management in Mixed Wireless Networks

      Dean, Richard; Astatke, Yacob; Morgan State University (International Foundation for Telemetering, 2010-10)
      This paper presents a model for Quality of Service (QoS) management in a mix of fixed Ground Station (GS) and ad-hoc telemetry networks, and introduces an enhanced clustering scheme that jointly optimizes the performance of the network using multiple distance measures based on the location of the wireless nodes and the traffic level. It also demonstrates that a "power" performance measure is an effective tool for modeling and managing QoS in Mixed Networks. Simulation results show that significant QoS performance improvements can be obtained and maintained even under severe traffic conditions.
    • The Range Area Network: A New Approach for Aeronautical Telemetry

      Rice, Michael; Tinubi, Oluwasegun; Brigham Young University (International Foundation for Telemetering, 2010-10)
      The concept of a range area network dedicated to the reception of telemetry from airborne test articles is explored. The range area network consists of ground-based radios that receive telemetry packets from an airborne test article and relay those packets through the network to a data sink (e.g., the main telemetry display and processing center). The network may use either "dumb" nodes or "smart" nodes and this choice presents a trade-off involving node complexity, network bandwidth, and required RF power. Using a somewhat idealized, but nonetheless realistic example at the Edwards AFB complex and link budgets based on the emerging iNET standard, we show that a network consisting of just 6 nodes reduces the L-band airborne transmitter power to 6W and the ground-based transmitters to 3W. If the airborne transmitter is restricted to 1W at L-band, then coverage can be provided by a grid of 50 nodes.
    • Range-Video Network (RNET)

      Berard, Alfredo; Buckley, Mark; Roach, John; Eglin Air Force Base; Teletronics Technology Corporation (International Foundation for Telemetering, 2010-10)
      The deployment of network-based airborne instrumentation systems is leading to cost-efficient replacement of legacy instrumentation systems. One application of airborne data acquisition that has been developed and maintained separately from traditional avionics and orange-wire data acquisition systems is high-speed camera packages. The development of network-based instrumentation systems has led to an opportunity to unify these two previously distinct airborne data acquisition activities. This paper describes the range-video network-based instrumentation system (rNET) being implemented by the 46th Test Wing, 846th Test Support Squadron at Eglin Air Force Base, FL to replace the existing Airborne Separation Video System (ASVS).
    • Recording in the iNET Architecture: Moving to the Future of Recording

      Cranley, Nikki; Corry, Diarmuid; ACRA Control (International Foundation for Telemetering, 2010-10)
      At the heart of many networked Flight Test Instrumentation (FTI) systems is the Network- Recorder. The high data rates typical in networked FTI systems put increased demands on the Network-Recorder to support ever faster read and write rates. However, thanks to the developments in CompactFlash and SATA technologies, such recording rates are achievable in the Network-Recorder. This paper discusses several ways in which the recorder can be optimized to improve the memory capacity usage, writing speed and relevance of the recorded data.
    • Reduced Complexity Viterbi Decoders for SOQPSK Signals over Multipath Channels

      Saquib, Mohammad; Kannappa, Sandeep Mavuduru; University of Texas at Dallas (International Foundation for Telemetering, 2010-10)
      High data rate communication between airborne vehicles and ground stations over the bandwidth constrained Aeronautical Telemetry channel is attributed to the development of bandwidth efficient Advanced Range Telemetry (ARTM) waveforms. This communication takes place over a multipath channel consisting of two components - a line of sight and one or more ground reflected paths which result in frequency selective fading. We concentrate on the ARTM SOQPSKTG transmit waveform suite and decode information bits using the reduced complexity Viterbi algorithm. Two different methodologies are proposed to implement reduced complexity Viterbi decoders in multipath channels. The first method jointly equalizes the channel and decodes the information bits using the reduced complexity Viterbi algorithm while the second method utilizes the minimum mean square error equalizer prior to applying the Viterbi decoder. An extensive numerical study is performed in comparing the performance of the above methodologies. We also demonstrate the performance gain offered by our reduced complexity Viterbi decoders over the existing linear receiver. In the numerical study, both perfect and estimated channel state information are considered.
    • A Reflection Type Phase Shifter for iNET Phase Array Antenna Applications

      Shrestha, Bikram; Morgan State University (International Foundation for Telemetering, 2010-10)
      In this article we present results from modeling and simulation of a L-band reflection type phase shifter (RTPS) that provides continuous phase shift of 0° to 360°. The RTPS circuit uses a 90º hybrid coupler and two reflective load networks consisting of varactor diodes and inductors. Proper design of 90° hybrid coupler is critical in realizing maximum phase shift. The RTPS circuit implemented on a Rogers Duroid substrate is large in size. We discuss methods to reduce the size of L-band RTPS.
    • Refraction Effects for Tracking Error at C- & S-Band Frequencies

      Oh, Chang Yul; Lee, Hyo Keun; Oh, Seung Hyeub; Korea Aerospace Research Institute; Chungnam National University (International Foundation for Telemetering, 2010-10)
      This document is focused on the examination of the tracking angular error due to the radio refraction for the target in low altitude of less than 5km and in low elevation angle. The real measured data using the GPS and the tracking systems of C- and S-band frequency in NARO Space centre, Korea are used for the analysis. The analysis shows couple of conclusions on the radio refraction effects; there are angular errors due to the radio refraction which is not to be neglected comparing the accuracy of the tracking system but to be considered for the precise measurement of the target position. Also, the refraction errors are dependent on the target altitude, but not on the frequency.
    • Remote Imaging System Acquisition (RISA) Space Environment Multispectral Imager

      Grubbs, Elmer; Marcellin, Michael; Lizarrage, Adrian; Lynn, Brittany; Lange, Jeremiah; University of Arizona (International Foundation for Telemetering, 2010-10)
      The purpose of the NASA Remote Imaging System Acquisition space camera prototype is to integrate multiple optical instruments into a small wireless system using radiation tolerant components. This stage of prototyping was the development of a broadband variable-focus camera that can transmit data wirelessly. A liquid lens in conjunction with a cerium doped double gauss eliminates traditional focusing mechanisms.
    • A Robotic Platform for Student System Design

      Kosbar, Kurt; Rodhouse, Kathryn; Ziegler, Steven; Huttsell, Ryan; Missouri University of Science and Technology (International Foundation for Telemetering, 2010-10)
      The goal of the project described in this paper, is to develop a platform for undergraduate engineering students to use in system analysis and design courses. We chose to develop an inexpensive robotic platform. The robot is intended to be autonomous, under the control of an on-board microcontroller. In the first revision of the hardware, a three wheeled design will be used, with the intention of being used indoors, on smooth surfaces. Students in their first year of college education will purchase the components, and assemble the robot. After analyzing the baseline design, they will be encouraged to incorporate new sensors and actuators in the subsequent laboratory courses.
    • Role of a Small Switch in a Network-Based Data Acquisition System

      Hildin, John; Teletronics Technology Corporation (International Foundation for Telemetering, 2010-10)
      Network switches are an integral part of most network-based data acquisition systems. Switches fall into the category of network infrastructure. They support the interconnection of nodes and the movement of data in the overall network. Unlike endpoints such as data acquisition units, recorders, and display modules, switches do not collect, store or process data. They are a necessary expense required to build the network. The goal of this paper is to show how a small integrated network switch can be used to maximize the value proposition of a given switch port in the network. This can be accomplished by maximizing the bandwidth utilization of individual network segments and minimizing the necessary wiring needed to connect all the network components.
    • Situational Wireless Awareness Network

      Marcellin, Michael W.; Xin, Hao; Scheidemantel, Austin; Alnasser, Ibrahim; Carpenter, Benjamin; Frost, Paul; Nettles, Shivhan; Morales, Chelsie; University of Arizona (International Foundation for Telemetering, 2010-10)
      The purpose of this paper is to explain the process to implementing a wireless sensor network in order to improve situational awareness in a dense urban environment. Utilizing a system of wireless nodes with Global Positioning System (GPS) and heart rate sensors, a system was created that was able to give both position and general health conditions. By linking the nodes in a mesh network line of sight barriers were overcome to allow for operation even in an environment full of obstruction.
    • SOQPSK Signals in Multiple Input Multiple Output (MIMO) Systems

      Kosbar, Kurt; Gupte, Abhishek; Missouri University of Science and Technology (International Foundation for Telemetering, 2010-10)
      This paper investigates the use of shaped offset quadrature phase shift keying (SOQPSK) signals in multiple-input multiple-output (MIMO) communication systems. The goal is to integrate commonly used receiver architectures for conventional single-input single-output (SISO) systems into a corresponding MIMO system. The benefits of improved spectral efficiency are juxtaposed against the increased receiver complexity. Bit error rate performances for the SISO and MIMO architectures in a multipath environment are compared and conclusions regarding trade-offs between signal to noise ratio (SNR) and spectral efficiency stated.
    • Switched for Networked FTI

      Cranley, Nikki; ACRA Control (International Foundation for Telemetering, 2010-10)
      Ethernet technology offers numerous benefits for networked Flight Test Instrumentation (FTI) systems such as increased data rates, flexibility, scalability and most importantly interoperability owing to the inherent interface, protocol and technological standardization. In a networked FTI system, the switch is a key component that allows data to be routed between Data Acquisition Units (DAU's), networked recorders, data processing and analysis stations. This paper provides an introduction to network switching concepts with a focus on its operation in a networked FTI system. The features of Commercial Off-The-Shelf (COTS) and FTI switches are compared demonstrating the benefits of FTI switches in terms of reliability, routing, throughput, latency, and start-up delays.
    • A TDMA-MAC Protocol for a Seismic Telemetry-Network with Energy Constraints

      Mayer, Gerhard; Höller, Peter; Höller, Yvonne; University of Salzburg (International Foundation for Telemetering, 2010-10)
      The requirements for a seismic telemetry-network are even more stringent than the well known problems of sensor networks. Existing medium access control (MAC) protocols suggest reducing energy consuming network activity by reducing costly transmissions and idle listening. Furthermore, it is required to set up communication patterns in different priority levels as well as ensuring fast handling of critical events. A protocol is proposed that operates with two parallel sets of time schedules in a time-division-multiple-access (TDMA) sense of periodic activity for listening and for transmitting. Synchronization packets sent from a central base station ensure optimal response times.
    • Telemetry Architectures for Future Earth Observation Missions: Over 1 Gbit/s in X-Band

      Guérin, A.; Lesthievent, G.; Issler, J.-L.; Centre National d’Etudes Spatiales (CNES) (International Foundation for Telemetering, 2010-10)
      High data rate payload telemetry of Earth Observation missions is classically done in the Earth Exploration Satellite (EES) X-band (8025-8400 MHz) with current max data rates about 600 Mbit/s. While higher frequency bands are often considered to offer higher data rates, this paper deals with on-board architectures that would allow data transmission at more than 1 Gbit/s in X-Band. It presents these new architectures based on spectrally efficient transmission systems and on simultaneous bipolarization transmission, their designs and their performances. Variable Coding and Modulation techniques are described. Interference between channels in cross-polarization is also evaluated.
    • Telemetry System for the Solar Miner VII

      Kosbar, Kurt; Guenther, Clinton; Mertens, Robert; Lewis, Adam; Missouri University of Science and Technology (International Foundation for Telemetering, 2010-10)
      This paper describes a telemetry system used in the Missouri S&T solar car, which competed in the American Solar Challenge. The system monitors parameters of a number of the on-board electronic and mechanical systems, and also the activities of the vehicle driver. This data is transmitted to a lead vehicle, where the support team analyzes the performance in real-time to optimize the vehicle's performance. In previous vehicles the data was displayed using a LabVIEW based user interface. In this work we will describe a custom software solution, which provides the team with additional flexibility to display and analyze the data.