• Convolutional Versus LDPC and Turbo Codes on the Rayleigh Fading Channel

      Ryan, William E.; Marcellin, Michael W.; Jagiello, Kristin; Cooper, Charlie; University of Arizona (International Foundation for Telemetering, 2009-10)
      We consider the performance of low-density parity-check (LDPC) codes, turbo codes and convolutional codes over the binary-input AWGN channel with flat Rayleigh fading. LDPC and turbo codes are capacity-approaching codes for long codewords. For short and medium codewords we seek to determine if they still outperform the industry-standard memory-6, rate-1/2 convolutional code. For a fixed SNR, the probability of error for the codes of interest are plotted as a function of codelength. We find that for very short codewords, the convolutional code performs best.
    • Coded SOQPSK-TG Using the Soft Output Viterbi Algorithm

      Perrins, Erik; Alam, Daniel; University of Kansas (International Foundation for Telemetering, 2009-10)
      In this paper we present a system-level description of a serially concatenated convolutional coding scheme for shaped offset quadrature phase shift keying, telemetry group (SOQPSK-TG). Our paper describes the operation of various system modules. In addition, implementation details and references for each module in the system are provided. The modified Soft Output Viterbi Algorithm (SOVA) is employed for decoding inner and outer convolutional codes. The modified SOVA possess strong performance and low-complexity cost. The comparison of the modified (SOVA) and Max-Log-maximum a posteriori (MAP) decoding algorithm is presented. The SOVA after a simple modification displays the same performance as Max-Log-MAP algorithm, which is demonstrated by the simulation results. The advantage of the simple implementation of the modified SOVA makes it superior to Max-Log-MAP for our purposes.
    • A Wireless Telemetry System to Monitor Gait in Patients with Lower-Limb Amputation

      Fan, Richard E.; Wottawa, Christopher R.; Wyatt, Marilynn P.; Sander, Todd C.; Culjat, Martin O.; Culjat, Martin O.; Center for Advanced Surgical and Interventional Technology (CASIT); UCLA; Naval Medical Center San Diego; Naval Health Research Center (International Foundation for Telemetering, 2009-10)
      Even after rehabilitation, patients with lower-limb amputation may continue to exhibit suboptimal gait. A wireless telemetry system, featuring force sensors, accelerometers, control electronics and a Bluetooth transmission module was developed to measure plantar pressure information and remotely monitor patient mobility. Plantar pressure characterization studies were performed to determine the optimal sensor placement. Finally, the wireless telemetry system was integrated with a previously developed haptic feedback system in order to allow remote monitoring of patient mobility during haptic system validation trials.
    • The Development and the Evaluation of a Quasi-Real Time Decision Aid Tool

      Leite, Nelson Paiva Oliveira; Lopes, Leonardo Mauricio de Faria; Walter, Fernando; Grupo Especial de Ensaios em Vôo; Instituto Tecnológico de Aeronáutica (International Foundation for Telemetering, 2009-10)
      In an experimental flight test campaign, the usage of a real time Ground Telemetry System (GTS) provides mandatory support for three basic essential services: a) Safety storage of Flight Tests Instrumentation (FTI) data, in the occurrence of a critical aircraft failure; b) Monitoring of critical flight safety parameters to avoid the occurrence of accidents; and c) Monitoring of selected parameters that validates all tests points. At the operational side the test ranges typically works in two phases: a) In real time where the GTS crew performs test validation and test point selection with Telemetry data; and b) In post mission where the engineering crew performs data analysis and reduction with airborne recorded data. This process is time consuming because recorded data has to be downloaded, converted to Engineering Units (EU), sliced, filtered and processed. The main reason for the usage of this less efficient process relies in the fact that the real time Telemetry data is less reliable as compared to recorded data (i.e. it contains more noise and some dropouts). With the introduction of new technologies (i.e. i-NET) the telemetry link could be very reliable, so the GTS could perform data reduction analysis immediately after the receipt of all valid tests points, while the aircraft is still flying in a quasi-real time environment. To achieve this goal the Brazilian Flight Test Group (GEEV) along with EMBRAER and with the support of Financiadora de Estudos e Projetos (FINEP) started the development of a series of Decision Aid Tools that performs data reduction analysis into the GTS in quasi-real time. This paper presents the development and the evaluation of a tool used in Air Data System Calibration Flight Tests Campaign. The application receives the Telemetry data over either a TCP/IP or a SCRAMnet Network, performs data analysis and test point validation in real time and when all points are gathered it performs the data reduction analysis and automatically creates HTML formatted tests reports. The tool evaluation was carried out with the instruction flights for the 2009 Brazilian Flight Test School (CEV). The results present a great efficiency gain for the overall Flight Test Campaign.
    • Post Processing Data Analysis

      Irick, Nancy; Raytheon Missile Systems (International Foundation for Telemetering, 2009-10)
      Once the test is complete, the job of the Data Analyst has begun. Files from the various acquisition systems are collected. It is the job of the analyst to put together these files in a readable format so the success or failure of the test can be attained. This paper will discuss the process of breaking down these files, comparing data from different systems, and methods of presenting the data.
    • Advantages of Using a Modular Architecture to Extenuate the Effects of Disruptive Technologies

      Khaburzaniya, Yason; L-3 Communications (International Foundation for Telemetering, 2009-10)
      Disruptive technologies affect every industry and often indicate the rate of technological advancement. Observing previous technological leaps can help ensure that the next disruptive technology innovation has less of an impact. Many methodologies that were developed to combat the high adoption costs of disruptive technologies in the field of computer engineering can be applied to the satellite and telemetry world. One such methodology is modular architecture in software.
    • 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.
    • Data Acquisition Blasts Off - Space Flight Testing

      Curry, Diarmuid; ACRA Control Inc. (International Foundation for Telemetering, 2009-10)
      In principle, the requirements for a flight test data acquisition system for space testing (launch vehicles, orbiters, satellites and International Space Station (ISS) installations) are very similar to those for more earth-bound applications. In practice, there are important environmental and operational differences that present challenges for both users and vendors of flight test equipment. Environmental issues include the severe vibration and shock experienced on take-off, followed by a very sharp thermal shock, culminating (for orbital vehicles) in a low temperature, low pressure, high radiation operating environment. Operational issues can include the need to dynamically adapt to changing configurations (for example when an instrumented stage is released) and the difficulty in Telemetering data during the initial launch stage from a vehicle that may not be recoverable, and therefore does not offer the option of an on-board recorder. Addressing these challenges requires simple, rugged and flexible solutions. Traditionally these solutions have been bespoke, specifically designed equipment. In an increasingly cost-conscious environment engineers are now looking to commercial off-the-shelf solutions. This paper discusses these solutions and highlights the issues that instrumentation engineers need to consider when designing or selecting flight test equipment.
    • Using Oracol® for Predicting Long-Term Telemetry Behavior for Earth and Lunar Orbiting and Interplanetary Spacecraft

      Losik, Len; Failure Analysis (International Foundation for Telemetering, 2009-10)
      Providing normal telemetry behavior predictions prior to and post launch will help to stop surprise catastrophic satellite and spacecraft equipment failures. In-orbit spacecraft fail from surprise equipment failures that can result from not having normal telemetry behavior available for comparison with actual behavior catching satellite engineers by surprise. Some surprise equipment failures lead to the total loss of the satellite or spacecraft. Some recovery actions as a consequence of a surprise equipment failure are high risk and involve decisions requiring a level of experience far beyond the responsible engineers.
    • Applying the iNET System Management Standard

      Grace, Thomas B.; Bertrand, Allison R.; Newton, Todd A.; Naval Air Systems Command (NAVAIR); Southwest Research Institute (International Foundation for Telemetering, 2009-10)
      The System Management Standard Working Group (SMSWG) of the integrated Network- Enhanced Telemetry (iNET) project has developed a standard for the management of the Telemetry Network System (TmNS). The introduction of Internet Protocol (IP) networks on test ranges has created the potential for greater flexibility and improved usability in the telemetry environment. This paper will discuss how to apply the TmNS System Management Standard to best take advantage of the new networking paradigm. Some of the benefits include the ability to monitor or change resource allocations (such as data subscriptions and network routes), detect fault conditions, or change configuration during any phase of a test. An example of a common test scenario will illustrate one example of how the Simple Network Management Protocol (SNMP) commands, queries, and events included in the System Management Standard may be used to extend the capabilities of the TmNS. The discussion topics will include discovering devices, monitoring status variables, receiving device events, performing configuration, and performing control from the TmNS Management Information Base (MIB). This scenario gives guidance to ranges and test conductors in selecting and using System Management capabilities.
    • Integrated Network Enhanced Telemetry (iNET) - Information Security in a Multi-Service Program

      O'Neal, Steve; Lukins, Jeff; Hodack, David; TYBRIN Corporation; Dynetics, Inc.; Patuxent River Naval Air Station (International Foundation for Telemetering, 2009-10)
      With increasing competition for communications capability on Department of Defense, DOD, test ranges, and mounting associated costs for sequential scheduling of test activities, DOD is investing in 21st century digital telemetry for test ranges. This upgrade, the first major overhaul in more than 30 years, promises utilization of common RF spectrum for multiple, simultaneous tests on a given test range. Implementing this capability while 1) assuring program test directors of test execution capability and 2) complying with information assurance (IA) requirements for all DOD Services is a significant, but not impossible, challenge. In this paper we present a path forward for implementation of Certification and Accreditation (C&A) requirements for multi- Service implementation of integrated Network Enhanced Telemetry (iNET) Initial Operational Capability (IOC).
    • Common Display System (CDS) at the NAVAIRWD Ranges

      Karr, Bill; Maxel, Matt; Watson, Errol; NAVAIRWD (International Foundation for Telemetering, 2009-10)
      The Common Display System (CDS) will provide all NAVAIRWD sites with a flexible Range real-time situational awareness and telemetry display/processing capability. CDS will have an extensible framework enabling all sites to quickly and conveniently develop Range unique plugins to accommodate new requirements or functionality not presently found in the applications common core plug-ins. Range unique plug-ins are separate and distinct from the application's common core engine.
    • 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.
    • Potential Solutions to Communications During Plasmasonic Flight

      Jones, Charles H.; Air Force Flight Test Center (International Foundation for Telemetering, 2009-10)
      At about Mach number 10 and above, a high energy plasma field forms around a vehicle. This plasma sheath has a high attenuation factor that can cause communications black out. No practical solutions to communicating through a plasma sheath are known. In addition to standard real time data needs for test, a driving requirement to solve this problem is that most solutions will have to be designed into the vehicle. Modifications of vehicles designed to travel at these Mach numbers, especially any exterior modifications, will be extremely difficult due to effects on aerodynamics, thermal protection, and the materials used. A list of possible solutions to communications through hypersonically induced plasma has been collected over several years. This list was added to and verified during the Workshop on Communications through Plasma during Hypersonic Flight. Pros and cons of these potential solutions have been discussed and documented as well. The workshop also included a vote by the attending experts on what solutions are most promising. This paper reviews these solutions, their pros and cons, and a recommended way forward to solving this problem.
    • 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).
    • Telemetry Recorders and Disruptive Technologies

      Kortick, David; Astro-Med, Inc. (International Foundation for Telemetering, 2009-10)
      Telemetry data recorders are not immune to the effects that a number of disruptive technologies have had on the telemetry industry. Data recorder designs today make use of data buses, storage types and graphical user interfaces that are constantly evolving based on the advances of personal computer and consumer electronics technologies. Many of these recorders use embedded designs that integrate disruptive technologies such as PCI Express for realtime data and signal processing, SATA interfaces for data storage and touchscreen technologies to provide an intuitive operator interface. Solid state drives also play a larger role in the latest recorder designs. This paper will explore the effects of these technologies on the latest telemetry recorders in terms of the benefits to the users, cost of implementation, obsolescence management, and integration considerations. The implications of early adoption of disruptive technologies will also be reviewed.
    • Development of a Synthetic Beamforming Antenna - From Drawing Board to Reality

      Kelkar, Anand; Lamarra, Norm; Vaughan, Thomas; Creative Digital Systems (International Foundation for Telemetering, 2009-10)
      Following-up on an ITC 2006 paper, "From RF to bits with Synthetic Beamforming", we follow the development and fielding of a Digital Beamforming (DBF) Antenna. This antenna, built for an airborne Telemetry application, supports 10 individual polarization-diverse beams and immediately converts RF to IF at the antenna element through a suite of LNBs. The IF is then digitized and all subsequent processing is performed through an array of 200+ FPGAs, including DBF, optimal combining, demodulation, and IF upconversion. We present our Model-Based Design approach, which allowed us to develop and test the system incrementally and rapidly, particularly during the transition from factory testing to flight operations, where several unexpected problems were discovered. Our software tool set enabled us to dissect the System behavior via post-mission replay, and our detailed simulations were instrumental in developing mitigation quickly. The System-level impacts and root causes of some of these issues are also discussed. We believe the flexibility of DBF and the modular software architecture were key in quickly mitigating many of these unforeseen real-world issues without hardware modification.
    • The Test and Training Enabling Architecture (TENA) Enabling Technology for the Joint Mission Environment Test Capability (JMETC) in Live, Virtual, and Constructive (LVC) Environments

      Hudgins, Gene; Poch, Keith; Secondine, Juana; TENA Software Development Activity (SDA) (International Foundation for Telemetering, 2009-10)
      The Joint Mission Environment Test Capability (JMETC) is a distributed live, virtual, and constructive (LVC) testing capability developed to support the acquisition community and to demonstrate Net-Ready Key Performance Parameters (KPP) requirements in a customer-specific Joint Mission Environment (JME). JMETC, using the Test and Training Enabling Architecture (TENA), provides connectivity to the Services' distributed test capabilities and simulations, and Industry test resources. TENA is well-designed for supporting JMETC events through its architecture and software capabilities which enable interoperability among range instrumentation systems, facilities, and simulations. TENA, used in major exercises and distributed test events, is also interfacing with other emerging range systems.
    • 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.
    • The Design of Web-Oriented Distributed Post-Flight Data Processing Network System

      Dang, Huaiyi; Zhang, Junmin; Wang, Jianjun; Chinese Flight Test Establishment (International Foundation for Telemetering, 2009-10)
      It talks about a distributed net-based flight test raw data processing system, web-oriented and application oriented. The system likes a normal one, consists of database servers, web servers and NAS storage server, but with the particular distributed task scheduler servers and the calculation servers. Each type server can be a team. The user can use WEB browser with the help of OCX control to setup his own processing task according to his need, choose which plane, which flight no., and defining the parameters, flight time segments, extracting rate etc to be processed. The system can accomplish the processing using the embedded application middleware, various data processing modules in database, with the scheduler servers and processing servers. The system can meet many users' demand of huge quantity non-structural flight raw data quickly and efficient processing at the short time, ensure the flight data enhanced management, to keep from copying and distributing the great quantity raw data inefficiently and out-of-management.