• Using the CCSDS File Delivery Protocol (CFDP) on the Global Precipitation Measurement mission

      Ray, Tim; NASA (International Foundation for Telemetering, 2004-10)
      The Consultative Committee for Space Data Systems (CCSDS) developed the CCSDS File Delivery Protocol (CFDP) to provide reliable delivery of files across space links. Space links are typically intermittent, requiring flexibility on the part of CFDP. Some aspects of that flexibility will be highlighted in this paper, which discusses the planned use of CFDP on the Global Precipitation Measurement (GPM) mission. The operational scenario for GPM involves reliable downlink of science data files at a high datarate (approximately 4 megabits per second) over a space link that is not only intermittent, but also one-way most of the time. This paper will describe how that scenario is easily handled by CFDP, despite the fact that reliable delivery requires a feedback loop.
    • THROUGHPUT AND LATENCY PERFORMANCE OF IEEE 802.11E WITH 802.11A, 802.11B, AND 802.11G PHYSICAL LAYERS

      Shah, Vishal; Cooklev, Todor; IEEE (International Foundation for Telemetering, 2004-10)
      IEEE 802.11e is an amendment of the medium-access control (MAC) layer of the standard for wireless local area networking IEEE 802.11. The goal of 802.11e is to provide 802.11 networks with Quality of Service (QoS). 802.11 has three physical layers (PHY) of practical importance: 802.11b, 802.11a, and 802.11g. 802.11a and 802.11g provide data rates between 6 and 54 Mbps, and 802.11b provides data rates of 5.5 Mbps and 11 Mbps. However these data rates are not the actual throughput. The actual throughput that a user will experience will be lower. The throughput depends on both the PHY and MAC layers. It is important to estimate what exactly is the throughput when the physical layer is 802.11a, 802.11b, or 802.11g, and the MAC layer is 802.11e. In other words, how does providing QoS change the throughput for each of the three physical layers? In this paper we provide answers to this problem. Analytic formulae are derived. The maximum achievable throughput and minimum delay involved in data transfers are determined. The obtained results have further significance for the design of high-throughput wireless protocols.
    • SOFT SEAMLESS SWITCHING IN DUAL-LOOP DSP-FLL FOR RAPID ACQUISITION AND TRACKING

      Weigang, Zhao; Tingyan, Yao; Jinpei, Wu; Qishan, Zhang; BeiHang University; Wuyi University (International Foundation for Telemetering, 2004-10)
      FLL’s are extensively used for fast carrier synchronization. A common approach to meet the wide acquisition range and sufficiently small tracking error requirements is to adopt the wide or narrow band FLL loop in the acquisition and tracking modes and direct switching the loop. The paper analyze the influence of direct switching on performance, including the narrow band loop convergence, transition time etc. and propose applying the Kalman filtering theory to realize the seamless switching (SS) with time-varying loop gains between the two different loop tracking state. The SS control gains for the high dynamic digital spread spectrum receiver is derived. Simulation results for the SS compared to the direct switching demonstrate the improved performance.
    • DYNAMIC TRACKING PHASED ARRAY DATA LINKS

      Brown, K. D.; Allen, Chris; NNSA-KCP; University of Kansas (International Foundation for Telemetering, 2004-10)
      This paper describes a flexible telemetry data link developed by National Nuclear Safety Administration’s Kansas City Plant (NNSA-KCP) and the University of Kansas (KU) in support of NNSA’s Remote Sensing Laboratory (NNSA-RSL) located at the Nevada Test Site. This data link is based on a beam steerable phased array antenna (PAA). The paper describes the PAA and the Airborne Measurement System (AMS) application requiring signal source tracking. It highlights flight test data collected during recent flight testing on the Nevada Test Site for the AMS.
    • Challenges of Optimizing Multiple Modulation Schemes in Transponder Design

      Fairbanks, John S.; L-3 Communications, Inc. (International Foundation for Telemetering, 2004-10)
      Increasing gate counts in FPGA’s create an option of offering multiple waveform demodulation and modulation within a single transponder transceiver. Differing data rates, channel schemes, and network protocols can be addressed with the flexibility of software-based demodulation and modulation. Increased satellite longevity and reliability are benefits of software-based transceiver design. Newer packaging technology offers additional capability in reducing form factor and weight of a transponder. A review of the challenges in combining each of the above to produce the next generation of transponders is the subject of this paper.
    • IntelliBus

      Rosenbauer, Tom; Cook, Paul; Rosenbauer Consulting; L-3 Communications (International Foundation for Telemetering, 2004-10)
      The IntelliBus network protocol provides an enabling technology for the next generation data acquisition system. IntelliBus provides greater data acquisition efficiency and reliability compared to other network protocols. This paper discusses the design considerations and implementation of a next generation Data Acquisition System incorporating IntelliBus with emphasis on the advantages of the new architecture over existing acquisition systems.
    • FIREWIRE: THE NEW 1553?

      Blott, Michaela; ACRA CONTROL (International Foundation for Telemetering, 2004-10)
      MIL-STD-1553 has served the flight community well. However, in recent years several new high-speed bus standards have emerged that outperform 1553 in various respects such as data throughput and increased address space. During this time, mission requirements - including video and audio - have become more data intensive. Although some of these busses were not initially designed for the avionics industry (such as Ethernet, FireWire, and FibreChannel), they are potentially of interest as high-speed commercial off-the-shelf (COTS) solutions for both set-up and data acquisition. These busses offer not only improved overall system performance, in terms of aggregate sampling rates, but also simplify existing data acquisition system architectures. They require fewer high-bandwidth links which can serve for both set-up and data. This paper examines some of these issues, focusing in particular on IEEE1394, better known as FireWire.
    • EVALUATION OF CONSTANT ENVELOPE OFFSET QUADRATURE PHASE SHIFT KEYING TRANSMITTERS WITH A SOFTWARE BASED SIGNAL ANALYZER

      Jefferis, Robert P.; TYBRIN Corporation (International Foundation for Telemetering, 2004-10)
      Off-line software based signal analysis can be a valuable tool for detailed examination of transmitter signal characteristics. This paper describes the Advanced Range Telemetry (ARTM) Constant Envelope (CE) offset quadrature phase shift keying (OQPSK) modulation analyzer. It was developed expressly for evaluation of FQPSK-B^(1), FQPSK-JR and shaped OQPSK transmitter signals. Rationale for its creation, underlying assumptions, computation methods, and examples of its data products are presented.
    • LDPC-BASED ITERATIVE JOINT SOURCE/CHANNEL DECODING SCHEME FOR JPEG2000

      Pu, Lingling; Wu, Zhenyu; Bilgin, Ali; Marcellin, Michael W.; Vasic, Bane; University of Arizona (International Foundation for Telemetering, 2004-10)
      This paper presents a joint source-channel decoding scheme based on a JPEG2000 source coder and an LDPC channel coder. At the encoder, JPEG2000 is used to perform source coding with certain error resilience (ER) modes, and LDPC codes are used to perform channel coding. At the decoder, after one iteration of LDPC decoding, the output codestream is then decoded by JPEG2000. With the error resilience mode switches on, the source decoder detects the position of the first error within each codeblock of the JPEG2000 codestream. This information is fed back to the channel decoder, and incorporated into the calculation of likelihood values of variable nodes for the next iteration of LDPC decoding. Our results indicate that the proposed method has significant gains over conventional separate channel and source decoding.
    • THE RAH-66 COMANCHE NETWORKED BASED DATA ACQUISITION SYSTEM

      Dehmelt, Chris; L3 Communications (International Foundation for Telemetering, 2004-10)
      Serial interfaces (RS232, RS422/485) have been the standard method of communications in traditional data acquisition systems. The role of these interfaces has been to supply a simple setup and control path between a host and the data acquisition master and little else. Today’s distributed data acquisition systems (DAS), which are comprised of many types of components including Ground Support Computers (GSC), Pilot Control Units (PCU), Data System Control Units (DSCU), Solid State Recorders (SSR), Data Acquisition Units (DAU) and Cockpit Instrumentation Data Systems (CIDS), are ideally suited to the use of Ethernet for not only setup functions, but for the distribution of acquired data and status to an unlimited number of users. Besides the obvious advantage of higher data rates, Ethernet provides other benefits such as greater data integrity, multi-host capability, and common programming interfaces. This paper details the integration of new L3 Communications - Telemetry East (L3-TE) Ethernet based software and hardware components that are part of the Comanche Data Systems equipment suite.
    • NETWORK TELEMETRY: A NEW DIGITAL ACQUISITION SYSTEM FOR AIRBUS A380 AIRCRAFT

      Delarue, Xavier; IN-SNEC company (International Foundation for Telemetering, 2004-10)
      Based on a fourty year experience in Telemetry, acquired on the European Space Program, IN-SNEC company (Zodiac group) has designed a versatile, modular and customable telemetry system for Airbus A380 aircraft program. This Aircraft Telemetry System (TMA-2000) comes with a large set of acquisition boards allowing numerous digital and analog inputs. The major innovation of this system lies in its modularity which allows the user to configure his acquisition chain in function of his monitoring needs and the use of an Ethernet link for its configuration as well as for telemetry output data flow.
    • DESIGN AND DEVELOPMENT OF WIRELESS FLUOROMETRY NETWORKS

      Doonan, Daniel J.; Wu, Mei-Su; Lee, Michael; University of California, Santa Barbara (International Foundation for Telemetering, 2004-10)
      This paper presents the design and development of a fluorometry sensor network with LED excitation. The design of the electronics in junction with the capability of LED excitation will significantly reduce the size and costs of the flrorometer units. The coverage and effectiveness of the sensing and monitoring capability will also be greatly enhanced by the addition of the wireless networks.
    • PERFORMANCE EVALUATION OF ETHERNET LAN BASED DISTRIBUTED TELEMETRY DATA NETWORK AND ITS EXTENSION USING ROUTER AND BRIDGE

      Sadhukhan, Gautam; Vinodia, Deepak; Sandhu, Manmohan; Integrated Test Range (International Foundation for Telemetering, 2004-10)
      This paper evaluates the performance as well as effectiveness of the High Speed Ethernet LANBased Distributed Telemetry Data Network Architecture. It also attempts to obtain a feasible solution for the Extension of LAN over High Performance Digital Modem via Routers and Bridges. With the advent of highly efficient broadband TCP/IP network and rapid growth of data traffic demand in the area of Telemetry Data Acquisition and Processing, one has to adopt a high bit rate PCM Telemetry Data Stream with the strategy of distributed task scheduling in multiprocessor environment. The proposed Telemetry System Architecture is adopted as a milestone to Modern Telemetry system. It incorporates various value added services for the performance evaluation of various flight vehicles providing authenticated data. This paper shows that by configuring the IP addresses of various nodes and router / bridges with V.35 interfaces, it is possible to extend the Telemetry Data on a local LAN to the remote LAN for display and high speed processing in real time. Necessary comparisons of performance of the existing to the proposed systems are presented.
    • IEEE 1451 SMART TRANSDUCER STANDARDS: STATUS, GOING WIRELESS, AND PULLING IT ALL TOGETHER

      Jones, Charles H.; Edwards Air Force Base (International Foundation for Telemetering, 2004-10)
      There are seven parts of the Institute of Electrical and Electronics Engineers (IEEE) 1451 Smart Transducer family of standards either approved, in work, or in review. These documents are providing a nonproprietary set of standards for the implementation of smart transducers (i.e., sensors and actuators). This paper overviews these standards and their status. In particular, the IEEE P1451.5, which addresses wireless transducers, and the IEEE P1451.0, which will provide a common high level architecture for the entire family, will be discussed. A reference model, which is being used as a focus for the IEEE P1451.0, will be introduced to help show the relation between all the members of the family.
    • SURVEY OF DETECTION METHODS FOR ARTM CPM

      Perrins, Erik; Rice, Michael; Brigham Young University (International Foundation for Telemetering, 2004-10)
      The ARTM Tier-2 waveform, called “ARTM CPM” in IRIG 106-04, has almost three times the spectral efficiency of PCM/FM and approximately the same detection efficiency. The improved spectral efficiency comes at the price of computational complexity in the receiver. The optimum receiver requires 128 real-valued matched filters and keeps track of the waveform state with a trellis of 512 states and 2048 branches. Various complexity reducing techniques are applied and the resulting loss in detection efficiency is quantified. It is shown that the full 512-state trellis is not required to achieve the desired detection efficiency: two different 32-state configurations were found to perform within one tenth of a dB of optimal. Noncoherent techniques are also evaluated. It is shown that the required complexity can be quite large to achieve a respectable detection efficiency. One noncoherent technique performed within 1.9 dB of the optimal with only 64 states, which is significant when considering the additional complexity savings of not having to track the carrier phase.
    • XML: A GLOBAL STANDARD FOR THE FLIGHT TEST COMMUNITY

      Corry, Diarmuid; Cooke, Alan; ACRA CONTROL (International Foundation for Telemetering, 2004-10)
      Much effort has been spent on developing physical layer standards to ease multi-vendor inter-operability. However as anyone familiar with real-life system integration knows a large gap exists in defining system configuration and set-up, not just between vendors but also between different groups on the base. Different solutions to this problem have been attempted (for example TMATS). However, the emergence of XML (eXtensible Markup Language) as a commercial standard presents a new opportunity to define a powerful and extensible tool for data-interchange between different systems. This paper introduces the self-documenting standard for information exchange that is XML. A generic model for flight test data acquisition is presented. Finally, an XML vocabulary (or schema) based on this model is proposed. This schema could form the basis for an industry wide XML standard to simplify the problem of data interchange between vendors, between programs, even between different databases in the same organisation.
    • Comparison of Wireless Ad-Hoc Sensor Networks

      Spinden, David; Jasper, Jeffrey; Kosbar, Kurt; University of Missouri – Rolla (International Foundation for Telemetering, 2004-10)
      There are a number of telemetry applications where it would be helpful to have networks of sensors that could autonomously discover their connectivity, and dynamically reconfigure themselves during use. A number of research groups have developed wireless ad-hoc sensor network systems. This paper reviews the state-of-the-art in wireless ad-hoc networks, examining the features, assumptions, limitations and unique attributes of some of the more popular solutions to this problem.
    • CHALLENGES TO FUTURE ON-BOARD FTI – SYSTEMS FOR FIGHTER TYPE AIRCRAFT

      Roth, Heinz; EADS Military Aircraft (International Foundation for Telemetering, 2004-10)
      The system architecture of an onboard FTI-System is specifically designed to fulfil highly demanding flight test requirements. Since these flight test requirements are steadily increasing with the growing complexity of test aircraft and mission systems, a corresponding improvement in the performance of the FTI-Systems is mandatory to satisfy those flight test demands. In addition, the individual test flights have to provide the maximum of flight test data obtainable in order to improve test efficiency and to cut project costs. Increased performance, miniaturisation, more reduced design and installation costs are the challenges for future system architectures. The developments of commercial and consumer electronics have an increasing influence on the layout of FTI-Systems.
    • NETWORK CONNECTIONS BEYOND IEEE 802.11

      Zettwoch, Robert N.; The Boeing Company (International Foundation for Telemetering, 2004-10)
      More and more aircraft system designs are incorporating a local-area-network (LAN) using either Fibre Channel (FC) or Ethernet. To date there hasn’t been a means for creating a FC node connection between an airborne network and a ground based FC network or for creating a reliable high-speed Ethernet connection between air and ground. Ethernet connections have had some success by using the IEEE 802.11 wireless LAN for these types of connections; however, these connections suffer from many inherent problems using this standard. Problems include the lack of telemetry spectrum control, security validation, high-speed data transfer efficiency, and channel acquisition time. This paper will describe a methodology that utilizes the IRIG-106 PCM standard for communicating between aircraft and ground-based networks. PCM can solve the aforementioned problems and it enables the user to take advantage of the many ARTM advances in PCM telemetry technology [1]. One such advance in technology has been the use of SOQPSK (Tier 1) or Multi-h CPM (Tier 2) to enable the user to effectively double or more their bandwidth efficiency compared to PCM/FM (or CPFSK) (Tier 0).
    • REAL-TIME GPS ATTITUDE DETERMINATION SYSTEM BASED ON EPOCH-BY-EPOCH™ TECHNOLOGY

      Bock, Yehuda; Macdonald, Thomas J.; Merts, John H.; Spires, William H., III; Bock, Lydia; Fayman, Jeffrey A.; Geodetics Inc.; MacroVision; Eglin Air Force Base (International Foundation for Telemetering, 2004-10)
      There are many civilian and military applications requiring precise attitude determination. Geodetics Inc. has demonstrated high-accuracy GPS attitude solutions using their Epoch-by- Epoch™ (EBE) technology. EBE technology provides computational algorithms for instantaneous differential GPS processing of raw GPS measurement data (pseudorange and carrier phase). One of the most significant advantages of EBE technology over conventional GPS Real-Time Kinematic (RTK) algorithms is in its instantaneous initialization and reinitialization capability. This capability eliminates re-initialization delays due to losses-oflock, such as occur during high-dynamic maneuvers. This paper provides empirical data that was gathered during a test program, sponsored by Eglin Air Force Base, to assess the performance in real time of EBE technology as it applies to attitude determination. Using simulated data from a high-dynamic (9’g) maneuver, EBE yielded real-time attitude with accuracy better than one tenth of a degree (0.038 - 0.083 degrees, one standard deviation), utilizing geodetic quality GPS receivers operating in dual- or single-frequency mode with antenna separation of 2 meters. GPS geodetic receivers with only single frequency capability yielded attitude with accuracy of between 0.044 - 0.176 degrees after 1.3% - 2.5% of the solutions were rejected as data outliers.