• Fiber-Optic Local Area Network for Real-Time Telemetry

      Bartley, Tom; Loral Instrumentation (International Foundation for Telemetering, 1988-10)
      For years, standard telemetry decommutators have proven the practical effectiveness and other advantages of using a data-driven (or data flow) broadcast bus for collecting, merging, and distributing continuous flow, real-time data. Bus length constraints have limited the use of the wideband broadcast bus to within a single chassis or closely mounted multiple chassis. Standard fiber-optic interfaces now make it possible to extend a real-time, greater than 5 million word/sec tag and data broadcast bus over kilometers at costs comparable to computer local area networks (LANs). Other advantages of this type of LAN include: no software protocol or handshaking, great flexibility in widely distributed processing and data base management, data security, and readily available off-the-shelf products. This paper discusses design considerations for conceptual networks, shows a sample design based on standard products, and suggests opportunities for product development for various types of network nodes. Also discussed are the implications to distributed processing and merging of real-time continuous data streams into the more blocked environment of general purpose computer processing and data base management.
    • A Flexible Telemetry Processor for Spacecraft Testing

      Leng, Christopher; Peet, Arthur; Jet Propulsion Laboratory/California Institute of Technology; Martin Marietta Astronautics Group (International Foundation for Telemetering, 1988-10)
      In the past, telemetry data systems in support of JPL flight projects -- such as Voyager and Galileo -- were designed specifically for each mission. Third-generation computers and minicomputers were combined into a distributed system, and many man-hours of software development were invested to meet each project's unique processing requirements. These systems were used to support the Spacecraft testing on the ground and -- later -- for mission operations after launch. The Magellan System Test Data Processing Subsystem (STDPS) marks a departure from these past designs. For the first time, a re-usable telemetry-processing subsystem has been designed that is flexible enough to meet the spacecraft-testing requirements of the present project -- and can be easily changed for future projects as well. These changes are all accomplished through a user-friendly, menu-oriented interface. Extensive software re-programming is no longer required. The Magellan spacecraft is being constructed for JPL by Martin Marietta Astronautics Group, Denver, Colorado. The STDPS is currently in Denver, supporting the spacecraft testing.
    • Flight Test of SDM Telemetry System

      Ming, Zheng; Qi-shan, Zhang; Beijing Institute Aeronautics and Astronautics (International Foundation for Telemetering, 1988-10)
      Orthogonal functions are the mathematical foundations of implementing multiplex transmission. Walsh functions are a set of functions which are orthogonal, normalized, and complete. They can also be used to accomplish multiplex transmission - constituting a new kind of telemetry system. In this paper, the constitutive principle of Walsh function telemetry system is introduced, the Walsh function telemetry system has already been built, the experiments performed recently on this system and the results of flight experiment are comprehensively discussed.
    • A Four-State Trellis-Coded 8-PSK Modulation Computer Simulation

      Kopp, Brian; New Mexico State University (International Foundation for Telemetering, 1988-10)
      The continuing growth of the telecommunications industry has created a steadily increasing need for higher performance communications systems - systems that can transfer data at faster rates while meeting stringent bit error rate requirements. In the case of satellite and mobile communications these same systems must also maintain minimum size and power consumption requirements. To help implement this industry demand computer simulations of communications systems can be a viable tool. Simulators can be used to demonstrate feasibility while maintaining minimum research and development costs during the design phase of these new and more complex communications systems. One type of system where simulation has proved helpful has been trellis-codedmodulation (TCM). This paper documents a simulation of a four-state trellis-coded eight- PSK modulation scheme currently being researched at New Mexico State University (NMSU). In the past simulations of convolutionally coded schemes have used binary symbols in the decoding process. In TCM the Euclidean space components of the modulation scheme are used in place of the binary symbols. The simulator under development incorporates these Euclidean signal components which are taken from an eight-PSK signal constellation. Soft-decision maximum likelihood decoding using trellis trace-back techniques are then applied to the Euclidean signal components to recover the simulated transmitted data. The simulator supplies the user with the number of undetected errors generated during a simulation as well as the bit error rate for a given signal to noise ratio. This simulator is intended to provide an environment for investigating improved communication system designs and it is hoped that the results that are obtained from such telecommunication simulators will help satisfy the ever increasing demands of the telecommunications industry. It should be noted that the research being conducted at NMSU on TCM is being directed by Dr. Frank Carden. The development of the simulator was conducted by the author to assist Dr. Carden in the continuing investigation of TCM.
    • Functional Component Approach to Telemetry Data Capture Systems

      Sabia, Steve; Hand, Sarah; NASA, Goddard Space Flight Center (International Foundation for Telemetering, 1988-10)
      To support the telemetry data rates and meet the needs of telemetry data users in the next decade, telemetry data capture systems will have to be radically different from today's systems. At Goddard Space Flight Center, the Mission Operations and Data Systems Directorate is developing the capability to build user specific data capture systems from a library of high performance hardware and software elements that satisfy standard data capture processing requirements. One or more telemetry functions are encapsulated in a single standard open bus system (e.g. VME, Multibus II, NuBus etc.) with supporting software to form a user data capture system. Each subsystem module (card or board) includes a local microprocessor supplying on board intelligence and programmability for changing requirements. Many of these subsystem designs include custom very large scale integration (VLSI) components to increase speed while minimizing cost and size. A standard hardware and software interface to each card subsystem is employed to simplify system integration in the open system environment.
    • Generic Decommutation Capabilities in the Space Flight Operations Center

      O'Brien, Robin A.; Jet Propulsion Laboratory/California Institute of Technology (International Foundation for Telemetering, 1988-10)
      A generic decommutation capability has been created as part of the Space Flight Operation Center's goal of developing a multi-mission telemetry system. Generic decommutation involves separating the algorithmic description for extracting data from the actual implementation of decommutation. This was done by creating a Decommutation Map Language, which allows mission designers to describe decommutation algorithms without the restrictions imposed by a standard programming language. A Decommutation Map Compiler converts this description into C code, which is then linked with a decommutation library to provide an executable decommutation program. So far, this approach has been used successfully to decommutate several different types of data.
    • Generic Telemetry Processing: Theory vs. Application

      Pettit, Richard L., Jr.; Telos, Inc.; Jet Propulsion Laboratory/California Institute of Technology (International Foundation for Telemetering, 1988-10)
      The Space Flight Operations Center (SFOC) is a generic suite of ground data systems software. One main subsystem of SFOC is the Telemetry Input Subsystem (TIS). Utilizing techniques for the abstract representation of data, the TIS has provided a flexible software base that can be used as a baseline for multiple spacecraft missions.
    • GPS: The Versatile Tool for Range Instrumentation

      Hoefener, Carl; Richardson, William; Interstate Electronics Corporation (International Foundation for Telemetering, 1988-10)
      The Global Positioning System (GPS) has made significant contributions in range instrumentation. It was the prime tracking method for both realtime range safety and metric tracking for the Trident II. Because of its many advantages, GPS will become the primary source of time, space, and position information (TSPI) on the ranges. Many activities requiring precision TSPI have already committed to GPS and others are planning on the application of GPS in the future for use on the ranges. GPS is also an extremely accurate time source, with timing accuracies of 10 nanoseconds obtainable worldwide. The range interoperability problem is solvable through the use of GPS as the TSPI source. There is little doubt that GPS will become the standard TSPI source for all test and training ranges.
    • A High Data Rate Airborne Rotary Recorder with Long Record Time

      Leung, Victor; DATATAPE Incorporated (International Foundation for Telemetering, 1988-10)
      Application of instrumentation recorders for data acquisition in hostile environments has for years been accomplished by means of longitudinal recorders specially designed for that application. DATATAPE Incorporated has been the leader in providing such recorders beginning with its MARS series. Two recent trends have impacted the applicability of these machines: the need for record times longer than can be provided by the longitudinal machines and the trend in the instrumentation industry to utilize digital recording techniques.
    • High Performance, Real-Time, Parallel Processing Telemetry System

      Powell, Richard L.; Williamson, Gale L.; Razavian, Farhand; Friedman, Paul J.; Loral Instrumentation (International Foundation for Telemetering, 1988-10)
      Flight test and signal and image processing systems have shown an increasingly voracious appetite for computer resources. Previous solutions employed special-purpose, bit-sliced technology to supplant costly general purpose computers. Although the hardware is less expensive and the throughput greater, the expense to develop or modify applications is very high. Recent parallel processor technology has increased capabilities, but the high applications development cost remains. Input/output (I/O) such as intermediate mass storage and display has been limited to transfer to general purpose or attached I/O computers. The PRO 550 Processing and Storage Subsystem of the System 500 was developed to provide linearly expandable, programmable real-time processing and an interface to distributed data acquisition subsystems. Each data acquisition subsystem can acquire data from multiple telemetry and other real-time sources. Processing resources are provided by one or more 8 MIPS (20 MFLOPS peak) processor modules, which utilize an array of predefined algorithms, algorithms specified by algebraic notation, or developed via high level languages (C and Fortran). Setup and program development occur on an external, general purpose color graphics workstation that is connected to the subsystem via an Ethernet network for command, control, and resultant data display. High-performance peripherals and processors communicate with each other via a 16-MHz broadcast bus, the MUXbus II, where any or all devices can acquire data elements called tokens. A token is a single MUXbus II word of 32 bits of data and a 16-bit tag to identify the word uniquely to the acquiring modules. The output of each device to the bus can be one or more tokens, but each device captures the bus to insert a single token. This ensures all devices receive equal priority and the MUXbus II is maximally utilized. This multiple instruction, multiple data (MIMD) architecture automatically schedules and routes data to processors or to I/O modules without control processor overhead. Traditional peripherals and administrative functions utilize the second subsystem bus, which is a traditional VMEbus. It controls the high performance devices while permitting the utilization of standard off-the-shelf controllers (e.g., magnetic tape, Ethernet, and bus controllers) for less demanding I/O tasks. A dedicated Bridge Module is the gateway for moving data between bus domains.
    • High Shock, Wideband, Miniature, Air Borne FM/FM Telemetry System

      Maoz, Michael; Svensson, Ake; Aydin Vector Division; Saab Missiles AB (International Foundation for Telemetering, 1988-10)
      Aydin Vector Division has received an order from Saab Missiles AB, Sweden, to develop an airborne, high shock, wideband FM/FM telemetry system. During 1985 (within a period of eight months) three such systems (FMT-780) were built and shipped to customer after successful testing in the plant. The testing included acceptance and qualification. Later on, the three systems were exposed to high shock testing/firing in Sweden. This paper describes the specifications of the system, the design approach that was used in order to meet these specifications, the systems conceptual mechanical and electrical structure, the packaging technique and some of the test results. As a result of the success of the program, Saab Missiles AB, awarded Aydin Vector Division with an additional order for sixteen, computer based, specially designed, miniature PCM/FM airborne telemetry systems. A paper describing these systems and the overall program is going to be published within the next two years.
    • High Speed Data Acquisition Systems

      Talmadge, Richard D.; Radmand, Mansour; Wright-Patterson Air Force Base; Aydin Vector Division (International Foundation for Telemetering, 1988-10)
      Air Force systems testing today requires that more and more data be acquired to a higher degree of accuracy and in fewer flights. This necessitates a new approach to dynamic data acquisition system design. In the past data acquisition organizations used either direct or FM recording techniques of one sort or another to acquire data for post test processing. This paper will outline the direction that this organization is taking to reduce the size of the installed system as well as the time and money required to maintain the system during the testing process. The system discussed provides a capability to acquire both static (DC) data and dynamic data up to 10,000 Hertz and has a dynamic range in excess of 120 dB.
    • High Speed Synchronizer Card Utilizing VLSI Technology

      Speciale, Nicholas; Wunderlich, Kristin; NASA, Goddard Space Flight Center (International Foundation for Telemetering, 1988-10)
      A high speed Synchronizer Card utilizing semi-custom and custom very large scale integration (VLSI) devices, microprocessor control, and programmable logic has been designed to provide a generic NASA Communication (NASCOM) block processing and telemetry frame synchronization function for present missions and Space Station era telemetry data streams at data rates up to 25 Mbps. The Synchronizer Card utilizes four distinct sets of VLSI semi-custom and custom chips to shrink all of the functions required for NASCOM block processing, telemetry frame synchronization, real time quality trailer appendage and cumulative quality statistic generation into a single Synchronizer card. This paper will describe the functions performed by the Synchronizer Card and each individual set of chips.
    • An Intelligent Digital Phase-Locked Loop with Integral Gain Control, Signal Quality and Lock Detection

      Melester, M. T.; Geoghegan, M. S.; Electrospace Systems, Inc. (International Foundation for Telemetering, 1988-10)
      An intelligent digital phase-locked loop with integral automatic gain control, signal quality and lock detection suitable for implementation using current digital signal processing devices is presented. By exploiting information derived from these functions operating in unison, it is possible to realize improved performance in an adverse environment where fading or abrupt signal outages are encountered. The system described consists of several functions operating under the direction of a stored program. The state diagram model of the program is discussed along with design considerations for the system elements. Various aspects of the system are simulated in the presence of noise and signal outage and compared to the performance of a conventional phase-locked loop.
    • International Telemetering Conference Proceedings, Volume 24 (1988)

      Unknown author (International Foundation for Telemetering, 1988-10)
    • The IPTN's Airborne Data Relay System (ADReS): A System Concept and the Phase One System Configuration

      Soelaiman, Adi Dharma; Roesma, Fauzi Effendy; Indonesian Aircraft Industry Ltd. (International Foundation for Telemetering, 1988-10)
      By making use of NC212-200 commuter aircraft as an airborne container, the ADReS, a short for airborne data relay system, had been configured and tested in an experimental status during the year of 1987. A kind of test on EMC, EMI, RFI and telemetry data link were applied to the system. Prior to the IPTN's flight test program in the year of 1988 - 1992, the ADReS is designed not only to receive and to relay the data, but also planed to be able to process the data for quick data analysis purposes on board. This paper describes the ADReS system concept and its experimental status system - the Phase One system configuration.
    • Mass Memory Reliability Evaluation for On-Board Data Recording Applications

      Goodwin, Paul F.; Capots, Larry H.; Austin, Howard R.; Fairchild Space Company (International Foundation for Telemetering, 1988-10)
      When properly implemented, solid state memory technology can result in mass data storage products with very large mean time to failure (MTTF). Fairchild Space Company has developed a memory architecture for their Solid State Recorder (SSR), which optimizes solid state performance in terms of survival probability (> 10 years), speed (~ 140 Mbps), size, weight and power compared to market alternatives such as magnetic tape, magnetic disc, magnetic bubble and optical disc. The basis for the memory design was an in depth investigation of the survival probability of very large quantities of interconnected memory devices.
    • MMTS: Multi-Vehicle Metric & Telemetry System

      Aspnes, Richard K.; Yuma, Russell J.; Control Data Corporation (International Foundation for Telemetering, 1988-10)
      The Multi-Vehicle Metric & Telemetry System (MMTS) is a complete range system which performs real-time tracking, command destruct, and telemetry processing functions for support of range safety and the test and evaluation of airborne vehicles. As currently configured, the MMTS consists of five hardware and software subsystems with the capability to receive, process, and display tracking data from up to ten range sensors and telemetry data from two instrumented vehicles. During a range operation, the MMTS is employed to collect, process, and display tracking and telemetry data. The instrumentation sites designated for operational support acquire tracking and telemetered data and transmit these data to the MMTS. The raw data is then identified, formatted, time tagged, recorded, processed, and routed for display to mission control and telemetry display areas. Additionally, processed tracking data is transmitted back to instrumentation sites as an aid to acquire or maintain vehicle track. The mission control area consists of a control and status console, high resolution color graphics stations, and large screen displays. As the mission controller observes mission progress on the graphics stations operational decisions can be made and invoked by activation of the appropriate console controls. Visual alarms provided my MMTS will alert mission control personnel of hazardous conditions posed by any tracked vehicle. Manual action can then be taken to activate transmission of the MMTS vehicle destruct signal. The telemetry display area consists of ten fully-functional, PC compatible computers which are switchable to either of two telemetry front end processors. Each PC can be independently set up by telemetry analysts to display data of interest. A total of thirty data pages per PC can be defined and any defined data page can be activated during a mission. A unique feature of the MMTS is that telemetry data can be combined with tracking data for use by the range safety functions.
    • Modem Simulations for Possible Use in Space Station

      Horan, Stephen; New Mexico State University (International Foundation for Telemetering, 1988-10)
      Two candidate modem structures for use in the Space Station Multiple Access Communications System were simulated using a software simulation package to obtain symbol error rate curves. These systems represent an evolutionary QPSK through 8-PSK modulation format for the input data streams. It was found through the simulations that the use of phase-staggered QPSK modems would give lower expected implementation loss than a modem based upon the Polarity Costas Loop method. However, the latter would represent a simpler hardware investment to realize the modem structure for both QPSK and 8-PSK.
    • NASA-GSFC Research Developments Evolve into HRSO Satellite Concepts

      Hilliard, Lawrence M.; NASA-GSFC (International Foundation for Telemetering, 1988-10)
      Shaped omni and modular array antenna concepts are being baselined for use on operations with the NASA Space Network and the High Resolution Solar Observatory (HRSO) Satellite Free Flyer Concept. This mission requires 16 MBPS return links, 1 KBPS multiple access links, and a completely redundant set of gimballed antennas to support these links with 90% continuous coverage from TDRSS (Tracking and Data Relay Satellite System). This presentation will discuss in detail how the flexibility of these components enabled mission planners to tradeoff spacecraft options without sacrificing mission objectives.