• Spectrally Efficient Concatenated Convolutional Codes with Continuous Phase Modulations

      Perrins, Erik; Damodaran, Kanagaraj; University of Kansas (International Foundation for Telemetering, 2008-10)
      We develop bandwidth-efficient serially concatenated coded (SCC) continuous phasemodulation (CPM) techniques for aeronautical telemetry. The concatenated code consists of an inner and an outer code, separated by an interleaver, and is decoded using relatively simple near-optimum iterative decoding algorithms. CPM waveforms such as shaped-offset quadrature phase shift keying (SOQPSK) and pulse code modulation/ frequency modulation (PCM/FM), which are currently used in military satellite and aeronautical telemetry standards, can be viewed as inner codes due to their recursive nature. For the outer codes, we apply serially concatenated convolutional codes (SCCC) because of their large coding gains, high coding rates, and because their decoding algorithms are readily implemented. High-rate codes are of special interest in aeronautical telemetry applications due to recent reductions in available spectrum and ever-increasing demands on data rates. We evaluate the proposed coding schemes with a large set of numerical simulation results and make a number of recommendations based on these results.
    • Turbo Product Code with Continuous Phase Modulation

      Perrins, Erik; Damodaran, Kanagaraj; University of Kansas (International Foundation for Telemetering, 2008-10)
      A basic problem statement in aeronautical telemetry has been to develop communication systems with good detection efficiency coupled with good spectral efficiency. Shaped-offset quadrature phase shift keying (SOQPSK) is a spectrally more efficient form of continuous phase modulation (CPM) as opposed to pulse code modulation/frequency modulation (PCM/FM). With these modulation techniques, we propose concatenated turbo product code (TPC) with CPM as a solution to our above problem statement. The performance of this turbo product coded CPM (TPC-CPM) system is simulated under coherent and non-coherent demodulation. Finally we present simulation results showing impressive coding gain performance of TPC-CPM over the AWGN channel.
    • A Constraint-Based Approach to Predictive Maintenance Model Development

      Gorman, Joe; Takata, Glenn; Patel, Subhash; Grecu, Dan; Charles River Analytics (International Foundation for Telemetering, 2008-10)
      Predictive maintenance is the combination of inspection and data analysis to perform maintenance when the need is indicated by unit performance. Significant cost savings are possible while preserving a high level of system performance and readiness. Identifying predictors of maintenance conditions requires expert knowledge and the ability to process large data sets. This paper describes a novel use of constraint-based data-mining to model exceedence conditions. The approach extends the extract, transformation, and load process with domain aggregate approximation to encode expert knowledge. A data-mining workbench enables an expert to pose hypotheses that constrain a multivariate data-mining process.
    • A Cross-Layered Protocol Architecture for Highly-Dynamic Multihop Airborne Telemetry Networks

      Perrins, Erik; Sterbenz, James P. G.; Jabbar, Abdul; University of Kansas (International Foundation for Telemetering, 2008-10)
      Highly-dynamic mobile wireless communication presents unique challenges to the network at all layers, and requires the design of new protocols and mechanisms. We discuss a cross-layer aware internetwork architecture and the various mechanisms to enable reliable communication in high-velocity multihop scenarios. We introduce AeroNP, an IP-compatible network protocol that is designed for telemetry applications in an aeronautical environment. A new routing algorithm is presented that leverages location information combined with snooping to forward packets in the absence of stable end-to-end routes along, with an implicit congestion control mechanism.
    • Non-Traditional Uses of the CCSDS Space Link Extension (SLE) Protocol

      Safigan, Brian; Lokshin, Kirill; Puri, Amit; CVG/Avtec Systems, Inc. (International Foundation for Telemetering, 2008-10)
      Space Link Extension (SLE) is a set of Consultative Committee for Space Data Systems (CCSDS) recommended standards for extending the space link from ground stations to other spaceflight mission ground facilities over a ground network, allowing distributed access to space link telecommand and telemetry services. The currently defined and implemented SLE recommendations are oriented around a traditional CCSDS telecommand and telemetry protocol set, which uses discrete telecommand frames that are encapsulated in Communication Link Transmission Units (CLTUs) for transport over the ground segment, and telemetry data encapsulated in Transfer Frames at the spacecraft. This paper discusses several non-traditional uses of the SLE services. The applications addressed within lie outside the discrete packet telecommand/telemetry subset of the SLE recommendations that are fully defined by CCSDS. This paper will focus on the use of the currently implemented SLE model to enable the transport of other forms of data, which may be subject to various transmission constraints, across the ground segment.
    • WSMR Telemetry Capabilities: Today's Technology in Telemetry

      Aguirre, Zoe; Beltran, Gabe; White Sands Missile Range (International Foundation for Telemetering, 2008-10)
      White Sands Missile Range is the largest overland test range in North America occupying over 3,200 square miles in Southern New Mexico and nearby territory. One of the most critical test elements at White Sand Missile Range is it's capabilities in the telemetry field. Much significant advancement in technology has given WSMR and the entire electronics world the ability to achieve new levels of data acquisition that were not achievable a decade ago. And as attention to our nation's defense is of high priority, White Sands Missile Range provides to highest levels of telemetry competence in the Western Hemisphere.
    • International Telemetering Conference Proceedings, Volume 44 (2008)

      International Foundation for Telemetering, 2008-10
    • Real-Time Transport Protocols for Telemetry Data and Signaling

      Cranley, Nikki; Corry, Diarmuid; ACRA Control Inc. (International Foundation for Telemetering, 2008-10)
      There are many network transport and application layer protocols that have been developed and designed for the delivery of time-sensitive and critical data over best-effort Ethernet networks. Choosing the appropriate protocols is crucial to ensuring the performance of the network for data transmission. Network layer protocols, such as TCP/IP or UDP/IP, determine the reliability of the data transmission while application layer protocols are designed to enhance the services of the underlying transport protocol. This paper will compare the Quality of Service (QoS) tradeoffs for both UDP and TCP. In this paper it is shown that UDP or TCP alone is insufficient to meet the transmission requirements of telemetry data and to overcome these limitations, an application layer protocol is required to enhance the delivery of real-time sensitive data. This paper presents the Real-time Transport Protocol (RTP) and proposes a RTP telemetry profile payload definition that provides complete payload self-description and up to 98% packetization efficiency.
    • Key Components in a Networked Data Acquisition System

      Corry, Diarmuid; ACRA Control Inc. (International Foundation for Telemetering, 2008-10)
      With the growing interest in networked data acquisition there has been a lot of focus on networked data acquisition systems. However, the requirements of a flight test instrumentation system go beyond networked DAU's. For example, a FTI network fabric has particular requirements for switches, time grandmasters, recorders, data servers and network terminals to the ground. This paper discusses these components and how they inter-operate in a single, fully networked system and discusses some FTI oriented requirements for same. Where relevant, we discuss the results of some experiments with network latencies; packet losses etc. and discuss some enhancements that can contribute to improved efficiency for flight test programs.
    • Approaches to Mitigate Disruption of Telemetry During Directed Energy Testing

      Keidar, Michael; Kundrapu, Madhusudhan; Kim, Minkwan; Boyd, Iain D.; Jones, Charles H.; Mork, Brian; The George Washington University; University of Michigan; Edwards Air Force Base (International Foundation for Telemetering, 2008-10)
      Testing of directed-energy weapon systems requires continuous radio-wave telemetry in order to characterize in situ the effect of irradiation on a target. The telemetry in these cases might be disrupted due to plasma formation causing communication blackout. In this paper several mitigation approaches, namely electrostatic and electromagnetic, are considered. The electrostatic mitigation approach takes into account that an electron depleted sheath is formed around the negatively biased electrode. This creates a 'hole' in the electron density distribution allowing radio communication through the plasma. The electromagnetic approach is based on formation of the ExB layer in the plasma, consequent plasma acceleration, and resulting decrease in the plasma density. In order to assess these mitigation approaches, one needs to characterize the plasma which is created as a result of laser irradiation on different target materials and under various laser beam power levels. We developed a model of the plasma formation which is based on a kinetic description of the Knudsen layer and a hydrodynamic description of the collision-dominated plasma region which is coupled with analyses of the heat transfer in the target material. The overall model describes the absorption of the laser energy by the target and the resulting temperature rise in the surface. This temperature rise then induces ablation of the target material. Laser energy absorption by the plasma plume created above the surface is also considered. Analysis of the ablation rate of various targets subject to directed energy impact was performed. We considered a typical multilayer structure consisting of black paint, titanium, and aluminum layers. For instance, it was found that the aluminum layer has the highest ablation rate, while the black pain layer has the smallest rate for a given surface temperature.
    • In-Bore Acceleration Measurements of an Electromagnetic Gun Launcher

      Bukowski, Edward F.; Brown, T. Gordon; Brosseau, Tim; Brandon, Fred J.; Aberdeen Proving Ground; Dynamic Science Inc. (International Foundation for Telemetering, 2008-10)
      The US Army Research Laboratory has been involved in the design and implementation of electromagnetic gun technology for the past several years. One of the primary factors of this research is an accurate assessment of in-bore structural loads on the launch projectiles. This assessment is essential for the design of mass-efficient launch packages for electromagnetic guns. If not properly accounted for, projectile failure can result. In order to better understand the magnitude of the in-bore loads, a data-recorder was integrated with an armature and on-board payload that included tri-directional accelerometers and magnetic field sensors. Several packages were launched from an electromagnetic railgun located at Aberdeen Proving Ground, MD. Substantial effort was placed on soft-catching the rounds in order to facilitate data recovery. Analysis of the recovered data provided acceleration and magnetic field data acquired during the launch event.
    • Game Theory and Adaptive Modulation for Cognitive Radios

      Sharma, Guarav (International Foundation for Telemetering, 2008-10)
      In a multi-user cognitive radio network, there arises a need for coordination among the network users for efficient utilization of the available electromagnetic spectrum. While adaptive modulation alone helps cognitive radios actively determine the channel quality metric for the next transmission, Game theory combined with an adaptive modulation system helps them achieve mutual coordination among channel users and avoids any possible confusion about transmitting/receiving through a channel in the future. This paper highlights how the concepts of game theory and adaptive modulation can be incorporated in a cognitive radio framework to achieve better communication for telemetry applications.
    • PAM-Based Timing Synchronization for ARTM Modulations

      Perrins, Erik; Bose, Sayak; Wylie-Green, Marilynn P.; University of Kansas; Nokie Siemens Networks (International Foundation for Telemetering, 2008-10)
      A reduced-complexity decision-directed timing recovery method for continuous phase modulation (CPM) is presented. The timing recovery method is based on the pulse amplitude modulation (PAM) representation - or Laurent representation - of CPM, and is applied to the family of three telemetry modulations: PCM/FM, SOQPSKTG, and ARTM CPM. This work is the next step in an ongoing effort to develop reduced-complexity PAM-based receiver methods for aeronautical telemetry. We quantify the steady-state tracking accuracy of the proposed timing recovery method and show that it performs very close to the theoretical limit given by the modified Cramer-Rao bound (MCRB).We also demonstrate that the proposed method is free of false-lock points for all three modulations.
    • Iterative Equalization for SOQPSK in Multipath Fading

      Lei, Qiang; Rice, Michael; Brigham Young University (International Foundation for Telemetering, 2008-10)
      This paper investigates the application of iterative equalization techniques to overcome multipath fading for shaped offset QPSK (SOQPSK) in aeronautical telemetry. Two iterative equalization techniques for turbo encoded SOQPSK are presented. The first is the optimal-MAP turbo equalizer for OQPSK. The second equalizer is the adaptive decision feedback equalizer. Simulation shows that in the presence of frequency selective multipath typically encountered in aeronautical telemetry, both of these equalizers exhibit impressive performance.
    • Utilization of an IEEE 1588 Timing Reference Source in the iNET RF Transceiver

      Lu, Cheng; Roach, John; Sasvari, George; Teletronics Technology Corporation (International Foundation for Telemetering, 2008-10)
      Synchronization of the iNET communication link is essential for implementing the TDMA channel access control functions within the transceiver MAC transport layer, and providing coherent signal demodulation timing at the transceiver PHY layer. In the following implementation, the 1588 timing reference source is the GPS receiver. Because it is being used in the Ground Station Segment and Test Article Segment, it becomes feasible to utilize the 1588 timing reference for cross-layer (MAC+PHY) iNET transceiver synchronization. In this paper, we propose an unified iNET transceiver synchronization architecture to improve iNET transceiver performance. The results of the synchronization performance analysis are given.
    • Re-Engineering PCM/FM as a Phase Modulation Scheme

      Punnoose, Ratish J.; Sandia National Laboratories (International Foundation for Telemetering, 2008-10)
      Historically, (PCM/FM) receivers have used simple detection schemes yielding low performance. Using multi-symbol detection methods, PCM/FM can be received with better error performance than either SOQPSK or multi-h CPM. We present an approximation by which PCM/FM can be reinterpreted as a phase modulation scheme, allowing the use of coherent detection techniques. This is backward compatible with existing receivers. We also present an extension by which the error performance of the approximated PCM/FM can be improved even further with no change to the spectral properties. This improved waveform can be used in systems where compatibility with existing frequency allocation schemes is required.
    • Hardware Discussion of a MIMO Wireless Communication System Using Orthogonal Space Time Block Codes

      Potter, Chris; Kosbar, Kurt; Panagos, Adam; Missouri University of Science and Technology; Dynetics, Inc. (International Foundation for Telemetering, 2008-10)
      Although multiple-input multiple-output (MIMO) systems have become increasingly popular, the existence of real time results to compare with those predicted by theory is still surprisingly limited. In this work the hardware description of a MIMO wireless communication system using orthogonal space time block codes (OSTBC) is discussed for two antennas at both the transmitter and receiver. A numerical example for a frequency flat time correlated channel is given to show the impact of channel estimation.
    • Soft Recovery Recording System for Interior and Exterior Ballistics Characterization

      Guevara, Mauricio; Flyash, Boris; US Army ARDEC (International Foundation for Telemetering, 2008-10)
    • Current Status of Adding GPS Tracking Capability to a Missile Telemetry Section

      Kujiroaoka, Scott R.; Fielder, Russell G.; Sandberg, Alvia D.; NAVAIR (International Foundation for Telemetering, 2008-10)
      Past presented papers have discussed the integration efforts of incorporating Central Test & Evaluation Investment Program (CTEIP) sponsored Joint Advanced Missile Instrumentation (JAMI) components (namely the JAMI TSPI Unit-JTU), Commercial off the Shelf (COTS) parts (e.g. ARTM Tier I SO-QPSK Transmitter, Encryptor and Thermal Battery), and in-house developed devices (such as PCM Encoder and Dual Band Antenna) into a five-inch diameter Missile Telemetry (TM) Section. A prototype of this TM Section has been built up and integrated into an All Up Round (AUR) Missile and twice flown as a Captive Carried Test Missile (CTM) on an F/A-18 jet with great success. This TM Section is in the process of undergoing flight qualification testing (including environmental and electro-magnetic interference-EMI tests). After which it will be ready for mass production. This paper will detail these current efforts. In addition, the effort to upgrade some Navy and Air Force Test Ranges (with JAMI Ground Stations and Decommutators/Demodulators) to track and gather data from this Missile containing the new TM section will be discussed. Future plans to incorporate Flight Termination System (FTS) capabilities into the TM section will be covered as well.
    • Antenna Array Beamforming Technology: Enabling Superior Aeronautical Communication Link Performance

      Lu, Cheng Y.; Zhang, Yimin; Wu, Jinsong; Cook, Paul; Li, Xin; Amin, Moeness; Teletronics Technology Inc.; Villanova University (International Foundation for Telemetering, 2008-10)
      In this paper, we propose the exploitation of array beamforming technology in high-speed aeronautical communication applications, e.g., the integrated Network Enhanced Telemetry (iNET) system. By flexible steering of beams and nulls, an array can enhance desired signals whereas the undesired signals such as interference and jammers are suppressed. The proposed adaptive beamforming technology is DSP-based and network-aware, and is designed for the use at aerial vehicle platforms to increase transmission power efficiency, improve receiving signal sensitivity, mitigate interference/multipath effects, and extend the communication range.