• EFFECTS OF NON- LINEAR AMPLIFICATION ON N-GMSK AND N-FQPSK SIGNAL STATISTICS

      Gonzalez, Maria C.; Branner, George R.; University of California (International Foundation for Telemetering, 2004-10)
      Digital modulation schemes that are power and bandwidth efficient are highly desirable. After non-linear amplification has been done, signal modulation schemes having constant or quasi-constant envelopes are not as susceptible to spectral regrowth as those with non-constant envelopes. Since such distortion generates interference in the adjacent channels, the power operation of the amplifier in non-constant envelope modulations is typically backed off, resulting in systems with reduced power efficiency. On the other hand, constant envelope modulation may have different bandwidth spectra. This paper examines the statistical characteristics of N-GMSK and N-FQPSK [1] signals to assess the bandwidth efficiency in the presence of amplifier nonlinearities.
    • Telemetry Best Source Selection at White Sands Missile Range

      Engler, Richard (Ray); Kirby, Johanna; White Sands Missile Range (International Foundation for Telemetering, 2004-10)
      Over the last year, the Telemetry Data Center at White Sands Missile Range has conducted extensive comparative testing between its’ 20 year old Best Source Selector and several “off the shelf” selectors currently available. This paper explores the concerns involved in the process of selecting a new Best Source Selector and examines the inherent problems and differences associated with the old and new selectors.
    • 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.
    • 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.
    • 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.
    • 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.
    • International Telemetering Conference Proceedings, Volume 40 (2004)

      International Foundation for Telemetering, 2004-10
    • 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.
    • EMI AND SOFTWARE IMPROVEMENTS TO THE SOLAR MINER IV TELEMETRY PROCESSOR

      DeConink, Chad; DeConink, Sarah; Dean, James; Martin, Brad; Kosbar, Kurt; University of Missouri (International Foundation for Telemetering, 2004-10)
      The UMR Solar Car uses a telemetry processor to collect, compute, and transmit data to the driver of the car and a nearby chase vehicle. The original processor had deteriorated from environmental extremes and vibration. There were also problems with electromagnetic interference from the high efficiency electric motor switching electronics, difficulties with the many unplanned additions made to the processor in the field, and the unstructured software that was becoming difficult to maintain. This project consists of creating a replacement telemetry system that is more robust mechanically, and electrically, substantially improving the EMI performance of the device, and reworking the hardware and software to make it easier to maintain and upgrade.
    • Implementation of A 30-Channel PCM Telemetry Encoder

      Kim, Jung Sup; Jang, Myung Jin; Agency for Defense Development (International Foundation for Telemetering, 2004-10)
      The function of a PCM telemetry encoder, installed in moving vehicles such as automobiles, aircraft, missiles, and artillery projectiles, is to transform many physical variables, such as velocity, shock, temperature, vibration and pressure, into digital data. Also, the encoder is required to make a data frame composed of digital input signals and frame synchronous data. The framed data is supplied to the input of a transmitter. There are three critical considerations in developing a PCM telemetry encoder to be installed in an artillery projectile. The first is the performance consideration, such as sampling rate, data receiving rate and data transmission rate. The second is the size consideration due to the severely limited installation space in an artillery projectile and the last is the power consumption consideration due to limitations of the munition’s power supply. To meet these three considerations, the best alternative is a one-chip solution. Using a commercially available TMS320F2812 DSP chip, we have implemented a 30-channel PCM telemetry encoder to process randomized data frames, composed of 16-channel analog data, 14-channel digital data and 2 frame synchronization data per data frame, at 10Mbps transmission baud rate. This paper describes the structure of the 30-channel PCM telemetry encoder and its performance.
    • A MULTIFUNCTION SATELLITE BACKHAUL SYSTEM FOR AIRCRAFT FLIGHT TEST APPLICATIONS

      Bell, John J. (Jack); Mileshko, James; Payne, Edward L.; Wagler, Paul; ViaSat, Inc. (International Foundation for Telemetering, 2004-10)
      This paper will present the design of a network used to receive and record sensor data and provide voice communications between a flight controller and the pilot of an aircraft undergoing flight testing in remote areas. The network utilizes a completely self-contained mobile tracking subsystem to receive and relay the sensor data and cockpit voice in real-time over a geostationary satellite. In addition to the aircraft tracking and data/voice relay functions, the system also provides local data recording at the mobile station, telephone and intercom connectivity between the mobile station and the control center, and remote equipment setup via the satellite link.
    • 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).
    • COMPARISON OF ALAMOUTI AND DIFFERENTIAL SPACE-TIME CODES FOR AERONAUTICAL TELEMETRY DUAL-ANTENNA TRANSMIT DIVERSITY

      Jensen, Michael A.; Rice, Michael D.; Anderson, Adam L.; Brigham Young University (International Foundation for Telemetering, 2004-10)
      The placement of two antennas on an air vehicle is one possible practice for overcoming signal obstruction created by vehicle maneuvering during air-to-ground transmission. Unfortunately, for vehicle attitudes where both antennas have a clear path to the receiving station, this practice also leads to self-interference nulls, resulting in dramatic degradation in the average signal integrity. This paper discusses application of unitary space-time codes such as the Alamouti transmit diversity scheme and unitary differential space-time codes to overcome the self-interference effect observed in such systems.
    • INTEGRATION OF S-BAND FQPSK TELEMETRY TRANSMITTERS AND GPS-BASED TSPI SYSTEMS WITH CLOSELY SPACED ANTENNAE – A SUCCESS STORY

      Selbrede, Robert W.; Pozmantier, Ronald; JT3 LLC (International Foundation for Telemetering, 2004-10)
      Modern spectrally efficient telemetry transmitters are beginning to find their way on a variety of airborne test platforms. Many of these platforms also include Global Positioning System (GPS)-based Time-Space-Position-Information (TSPI) instrumentation systems. Due to space and other limitations, many of these platforms have demanding antenna placement limitations requiring closely spaced antennas. This paper describes steps taken to identify and mitigate potential interference to GPS-based TSPI instrumentation systems by these new technology transmitters. Equipment characterization was accomplished to determine interference potential of the proposed new transmitters and susceptibility of several GPS TSPI receivers. Several filtering techniques were identified as possible solutions to the anticipated interference problems. Telemetry (TM)/GPS system mockups and laboratory tests of the same were accomplished. Open-air testing was then accomplished to validate laboratory results. Finally, on aircraft tests were accomplished prior to performing any aircraft system modifications. Results of these test efforts are presented for others to consider when planning similar modifications to other platforms.
    • ADVANCED INSTRUMENTATION CONTROL SYSTEMS FOR F/A-18E/F

      Baker, Grady; NAVAIR (International Foundation for Telemetering, 2004-10)
      The purpose of this paper is to present the use of production aircraft equipment and wiring for control of the onboard instrumentation system. The major advantages and challenges associated with the use of existing production equipment versus dedicated instrumentation wiring and hardware will be explored. Many of the issues raised, including non-interference with existing avionics, are complex. It is the hope of the author that this paper will generate awareness and discussion on these issues.
    • 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.
    • JOINT RANGE SYSTEMS INTEROPERABILITY ACHIEVED THROUGH THE IMPLEMENTATION OF THE TEST AND TRAINING ENABLING ARCHITECTURE (TENA)

      Hudgins, B. Gene; Lucas, Jason; TENA; Eglin Air Force Base (International Foundation for Telemetering, 2004-10)
      The Foundation Initiative 2010 (FI 2010) project, sponsored by the Office of the Secretary of Defense (OSD) Central Test and Evaluation Investment Program (CTEIP), has developed and is continuing to refine a common architecture and requisite software used to integrate testing, training, and simulation systems distributed across many DoD test and training range facilities. The Test and Training Enabling Architecture (TENA), has been successfully implemented on DoD and commercial range instrumentation systems, used as a reusable enabler of distributed, live United States Joint Forces Command (USJFCOM) and Joint National Training Capability (JNTC) exercises.