• End-to-End ARQ: Transport-Layer Reliability for Airborne Telemetry Networks

      Sterbenz, James P. G.; Pathapati, Kamakshi Sirisha; Rohrer, Justin P.; University of Kansas (International Foundation for Telemetering, 2010-10)
      Due to the mission-critical nature of command-and-control traffic in the telemetry environment, it is imperative that reliable transfer be supported. The AeroTP disruption-tolerant transport protocol is intended for this environment. The mechanism for reliable transfer is ARQ with end-to-end acknowledgments. This has significant performance limitations resulting from the highly-dynamic nature of airborne telemetry networks, since end-to-end paths may not persist long enough for retransmissions to be received. We use ns-3 to analyze the AeroTP ARQ mechanism, along with tunable parameters that may improve performance in reliable transfer mode.
    • An Enhancement of Existing RF Data Links Using Advanced Diversity Techniques

      Melicher, Milos; ACRA Control (International Foundation for Telemetering, 2010-10)
      The theoretical capacity of communication channel in the presence of additive white Gaussian noise (AWGN) as defined by Shannon's channel capacity theorem has been well understood since 1940s. This theorem bounds the bit error rate (BER) of RF data links achievable for a particular noise level. The development in digital technology over the last decade has made it possible not just to design devices that operate close to the Shannon's limit, but also to explore techniques, such as best source and best data selectors, for further improvements in performance of RF data links where frequency, spatial or polar diverse reception is possible. This paper discusses an approach to improving quality of data links using an advanced diversity technique that does not select one source at a time but aligns and combines soft values from each. It shows how the overall bit error rate of RF data link can be improved by combining signals from multiple receivers and/or transmitters. Test results showing practical performance improvements are presented and discussed.
    • FTI Network Discover, Health, and Status Monitoring

      Cranley, Nikki; ACRA Control (International Foundation for Telemetering, 2010-10)
    • Hardware-Efficient Implementation of the SOVA for SOQPSK-TG

      Perrins, Erik; Hosseini, Ehsan; Rea, Gino; University of Kansas (International Foundation for Telemetering, 2010-10)
      In this paper, we present a hardware-efficient architecture of a demodulator for shaped offset quadrature phase shift keying, telemetry group version (SOQPSK-TG). The demodulation is done using the soft-output Viterbi algorithm (SOVA), which is implemented by the two-step traceback method. In this method, two traceback operations are employed to find the maximum-likelihood (ML) path and the competing path. Using the proposed architecture, the tracebacks are done at the same time as the demodulator is generating output bits and their reliabilities. This method has been shown to require less storage than the well-known register-exchange method. Finally, we present the performance results from the FPGA implementation.
    • Helicopter Slip Ring Replacement System

      Adamson, Alan; Berdugo, Albert; Flight Test Instrumentation; Teletronics Technology Corporation (International Foundation for Telemetering, 2010-10)
      Most helicopter programs require the acquisition of parameters from the rotating systems. Historically, these systems made use of electromechanical slip rings for the transfer of power, control, and data from within the helicopter's cabin to the rotating hardware. Slip rings are primarily used in dedicated instrumentation vehicles and are not commonly used in production platforms that may require instrumentation of the rotating systems for in-service load and fatigue monitoring. Additionally, the use of slip rings requires time and money to integrate the hardware and equipment into the aircraft in order to perform rotor data acquisition. The time needed to perform modifications to transmissions and drive trains plays a big factor in the increased costs of aircraft development. Less intrusive installations would minimize the need for mechanical changes and would improve the time needed to install the instrumentation. This paper describes a wireless system approach to perform the test without the slip ring, and provides performance data that validates this new method of instrumenting unobtrusively to save time and money without sacrificing data integrity.
    • High Data Rate ARTM Tier II Telemetry Waveforms Receiver Analysis and Design

      Dourbal, Paul; Bouglo, Yuriy; Fleyshman, Val; Mayer, Robert; Okoro, Jerry; Shikhalev, Boris; L-3 Telemetry East (International Foundation for Telemetering, 2010-10)
      In this article we show how phase noise and demodulator complexity define the potential performance of high data rate telemetry receivers for ARTM continuous phase modulation (ARTM CPM) signals. Given a level of phase noise and demodulator complexity, we can predict the potential performance of a receiver. We also provide the results of actual receiver performance measurements (obtained using RCB-4000 Telemetry Receiver). We develop a simplified analytical model for an ARTM CPM signal transmission and present the resulting equation for phase increment difference between close signal sequences. The analysis of demodulator performance deterioration due to inter-symbol interference and due to receiver phase noise is then provided. Actual receiver phase noise data is included and is used to analyze demodulator performance.
    • How to Use Analog Telemetry to Produce Equipment with 100% Reliability

      Losik, Len; Failure Analysis (International Foundation for Telemetering, 2010-10)
      Equipment reliability is driven by infant mortality failures, which can be eliminated using a prognostic analysis prior, during and/or after the exhaustive and comprehensive dynamic environmental factory acceptance testing which conducted to increase equipment reliability by identifying equipment that fails during test for repair/replacement. To move to the 100% reliability domain, equipment dynamic environmental factory testing should be followed by a prognostic analysis to identify the equipment that will fail within the first year of use. During all equipment testing, only equipment functional performance is measured and equipment performance is unrelated to short-term or long-term equipment reliability making testing alone inadequate to produce equipment with 100% reliability. A prognostic analysis converts performance measurements to reliability measurements invasively by sharing test data used to measure equipment performance. Performance data that is converted to reliability data provides a time-to-failure (TTF) in minutes/hours/days/months for equipment that will fail within the first year of use, allowing the production of equipment with 100% reliability, decreasing risk and making getting to space safe and reliable.
    • A Hybrid Data Acquisition Architecture on the CH-53K Program

      Dehmelt, Chris; L3 Communications Telemetry East (International Foundation for Telemetering, 2010-10)
      As today's flight test programs need for sensor and bus data continue to increase, there has been associated requirements to provide modern system output products and support higher encoder data rates. The CH-53K Heavy Lift Replacement (HLR) Program is an example in which the instrumentation data requirements have increased significantly over previous helicopter programs and necessitated the introduction of new technologies and capabilities. The CH-53K Program utilizes a hybrid system architecture that combines the benefits of legacy PCM and modern networked system architectures. The system provides for maintaining the required system-wide synchronized sampling capabilities, while providing real-time data access and system control over a vehicle network. Serial Streaming Telemetry (SST)-to-vNET Adapters are employed to enable many of these capabilities. This paper describes the instrumentation requirements for the CH-53K program and the features, tools and performance of its data acquisition system - which addressed all requirements while minimizing the overall impact to the existing instrumentation infrastructure.
    • IHAL and Web Service Interfaces to Vendor Configuration Engines

      Hamilton, John; Darr, Timothy; Fernandes, Ronald; Sulewski, Joe; Jones, Charles; Knowledge Based Systems, Inc.; L-3 Telemetry East; Edwards Air Force Base (International Foundation for Telemetering, 2010-10)
      In this paper, we present an approach towards achieving standards-based multi-vendor hardware configuration. This approach uses the Instrumentation Hardware Abstraction Language (IHAL) and a standardized web service Application Programming Interface (API) specification to allow any Instrumentation Support System (ISS) to control instrumentation hardware in a vendor neutral way without requiring non-disclosure agreements or knowledge of proprietary information. Additionally, we will describe a real-world implementation of this approach using KBSI‟s InstrumentMap application and an implementation of the web service API by L-3 Communications Telemetry East.
    • iNET Standards Validation: End-to-End Performance Assessment

      Moodie, Myron L.; Araujo, Maria S.; Grace, Thomas B.; Malatesta, William A.; Abbott, Ben A.; Southwest Research Institute; Naval Air Systems Command (NAVAIR) (International Foundation for Telemetering, 2010-10)
      The integrated Network-Enhanced Telemetry (iNET) project has developed standards for network-based telemetry systems. While these standards are based largely on the existing body of commercial networking protocols, the Telemetry Network System (TmNS) has more stringent performance requirements in the areas of latency, throughput, operation over constrained links, and quality of service (QoS) than typical networked applications. A variety of initial evaluations were undertaken to exercise the interfaces of the current standards and determine real-world performance. The core end-to-end performance initial evaluations focus collectively on the movement of telemetry data through the TmNS. These initial evaluations addressed two areas: end-to-end data delivery and parametric data extraction. This paper presents the approach taken by these ongoing efforts and provides initial results. The latest results will be presented at ITC 2010.
    • iNET System Management Scaling

      Bertrand, Allison R.; Newton, Todd A.; Grace, Thomas B.; Southwest Research Institute; Naval Air Systems Command (NAVAIR) (International Foundation for Telemetering, 2010-10)
      The integration of standard networking technologies into the test range allows for more capable and complex systems. As System Management provides the capability for dynamic allocation of resources, it is critical to support the level of network flexibility envisioned by the integrated Network-Enhanced Telemetry (iNET) project. This paper investigates the practical performance of managing the Telemetry Network System (TmNS) using the Simple Network Management Protocol (SNMP). It discusses the impacts and benefits of System Management as the size of the TmNS scales from small to large and as distributed and centralized management styles are applied. To support dynamic network states, it is necessary to be able to both collect the current status of the network and command (or modify the configuration of) the network. The management data needs to travel both ways over the telemetry link (in limited bandwidth) without interfering with critical data streams. It is important that the TmNS's status is collected in a timely manner so that the engineers are aware of any equipment failures or other problems; it is also imperative that System Management does not adversely affect the real-time delivery of data. This paper discusses measurements of SNMP traffic under various loading conditions. Statistics considered will include the performance of SNMP commands, queries, and events under various test article and telemetry network loads and the bandwidth consumed by SNMP commands, queries, and events under various conditions (e.g., pre-configuration, normal operation, and device error).
    • iNET System Operational Flows

      Grace, Thomas B.; Abbott, Ben A.; Moodie, Myron L.; Southwest Research Institute; Naval Air Systems Command (NAVAIR) (International Foundation for Telemetering, 2010-10)
      The integrated Network-Enhanced Telemetry (iNET) project is transitioning from standards development to deployment of systems. In fielding a Telemetry Network System (TmNS) demonstration system, one must choose and integrate technological building blocks from the suite of standards to implement new test capabilities. This paper describes the operation of a TmNS and identifies the management, configuration, control, acquisition, and distribution of information and operational flows. These items are discussed utilizing a notional system to walk through the mechanisms identified by the iNET standards. Note that at the time of this paper the efforts discussed are only at the very beginning of the design process and will likely evolve throughout the design process.
    • Information Assurance (IA) Considerations for a Telemetry Network System (TmNS)

      Hodack, David; Naval Air Systems Command (International Foundation for Telemetering, 2010-10)
      The integrated Network Enhanced Telemetry (iNET) project was launched by the Central Test and Evaluation Investment Program (CTEIP) to foster network enhanced instrumentation and telemetry. The iNET program is preparing for the TmNS system demonstration. The goal of the demonstration is to prove that the proposed TmNS will meet the Test Capability Requirements Document (TCRD) and validate the iNET standards. One aspect of the preparation is looking at the IA issues and making decisions to ensure that the system will be certified and accredited, meet user needs, and be secure. This paper will explore a few of these considerations.
    • An Integrated Data Acquisition System for Parachute Development and Qualification Testing

      Starbuck, Philip; PSG and Associates (International Foundation for Telemetering, 2010-10)
      The development and qualification of personnel and cargo aerial delivery parachute systems present unique challenges to the instrumentation and data analysis engineers. Some of the areas that must be addressed include: a) system must be low in cost, b) system often has to be operated on ranges that have limited telemetry or other range instrumentation and support (i.e. commercial skydiving centers), c) system is often rigged and operated by parachute support personnel and test jumpers rather than instrumentation engineers, and d) system must be able to be reconfigured in the field to support a variety of test card requirements during a typical test day, e) data must be available for review and the system be prepared for the next test within a few minutes of parachute recovery, and f) system must withstand ground impact velocities as high as 50 ft/sec (15.24 m/sec) without damage. This paper describes such a system as it is being used for the development and qualification testing of a number of parachute systems for sport skydiving, military personnel, as well as cargo parachute systems. This modular system has been developed as a result of previous experience in other parachute development and qualification projects to address the need for a flexible Data Acquisition System (DAS) system that meets the above requirements. This paper describes some of the tools used to meet these requirements.
    • Integrating Wireless Sensor Technologies into Instrumentation and Telemetry Systems

      Araujo, Maria S.; Moodie, Myron L.; Willden, Greg C.; Thibodeaux, Ryan J.; Abbott, Ben A.; Southwest Research Institute (International Foundation for Telemetering, 2010-10)
      Recent technological advancements in low-power, low-cost, small-footprint embedded processors, sensors, and radios are resulting in the very rapid growth of wireless sensor network deployments. Wireless sensor networks merge the scalability and distributed nature of networked systems with the size and energy constraints of remote embedded systems. With the ever increasing need to develop less intrusive, more scalable solutions for instrumentation systems, wireless sensor technologies present several benefits. They largely eliminate the need for power and network wiring, thus potentially reducing cost, weight, and deployment time; their modularity provides the flexibility to rapidly change instrumentation configurations and the capability to increase the coverage of an instrumentation system. While the benefits are exciting and varied, as with any emerging technology, many challenges need to be overcome before wireless sensor networks can be effectively and successfully deployed in instrumentation applications, including throughput, latency, power management, electromagnetic interference (EMI), and band utilization considerations. This paper describes some approaches to addressing these challenges and achieving a useful system.
    • Integrity Analysis and Fault Detection of Flight Test Data

      Glenn, Gregory J.; Duong, Nhattrieu; Speyer, Jason L.; Sysense, Inc. (International Foundation for Telemetering, 2010-10)
      Undetected sensor malfunctions during flight testing can lead to cost overruns and program delays. Determining the presence of these faults in a timely manner allows the operator to mitigate their effect. One way to detect these faults is to use a priori knowledge of sensor calibration data and system dynamics to calculate measurement uncertainties. These can then be used to determine the integrity of the sensor data and report violations of expected sensor behavior. Analytical redundancy methods and residual processing can be used in conjunction with a priori sensor information to detect faults otherwise unobserved with single-instrument data as well as to isolate and identify failure modes. These simulation and analysis methods have been implemented as MATLAB® Simulink® blocks and were used to model the flight instruments, detect anomalies in the navigation instruments, and locate the origin of the errors of a flight test data set.
    • International Telemetering Conference Proceedings, Volume 46 (2010)

      International Foundation for Telemetering, 2010-10
    • Introduction to XidML 3.0 An Open XML Standard for Flight Test Instrumentation Description

      Cooke, Alan; Herbepin, Christian; ACRA Control; Eurocopter (International Foundation for Telemetering, 2010-10)
      A few years ago XidML was introduced as an open XML standard for capturing the meta-data associated with flight test instrumentation (FTI). This meta-data schema was broken down into elements for Parameter (name, range, units, offset-binary), Instrument (name, serial number, misses-to loss), Package (bits per word, words per minor-frame, rate) and Link (name, type) and so on. XidML remains one of the only published schema for FTI meta-data and with XidML 3.0 many simplifications have been introduced along with support for nested tree structures and a single instrument schema allowing anyone to define the validation for instruments from any vendor. This paper introduces the XidML schema and describers the benefits of XidML 3.0 in particular. It begins by giving a brief description of what XidML is and describes its history and motivation. The paper then outlines the main differences between XidML-3.0 and earlier versions, and how the XidML schema has been further refined to meet the challenges faced by the FTI community. As an example of usage the FTIManager software developed at Eurocopter will be briefly presented in order to illustrate the XidML ability to describe a multi-vendor FTI configuration.
    • L-3 Communications 3rd Generation Telemetry Transmitter ST-5000 L/S/C Band Architecture and Design Efforts

      Wang, Wearn-Juhn; Martz, David; Hutzel, Kevin; L-3 Communications Telemetry East; L-3 Communications Nova Engineering (International Foundation for Telemetering, 2010-10)
      This paper presents the architecture and design efforts for L-3 3rd generation telemetry transmitter ST-5000. A Modulator/Upconverter with a low phase noise PLL synthesizer, a highly efficient and rugged power amplifier module with the multistage GaN HEMT devices and a high power density buck-boost power supply are discussed.
    • L-Band Coplanar Slot Loop Antenna for iNET Applications

      Nithianandam, Jeyasingh; Morgan State University (International Foundation for Telemetering, 2010-10)
      In this article we present a design of an L-band slot loop antenna with a dielectric loaded conductor backed coplanar waveguide (CBCPW) feed. The coplanar slot loop antenna has a transmission line resonator in series. We used full wave electromagnetic simulations with Ansoft's high frequency structure simulator (HFSS) software in the design of the coplanar slot loop antenna. The series transmission line resonator helps to tune the coplanar slot loop antenna and reduce its size. We present here results on return loss and radiations patterns of coplanar slot loop antenna obtained from HFSS simulations.