• Space Flight Operations Center Local Area Network: Hardware Design

      Goodman, Ross V.; Jet Propulsion Laboratory/California Institute of Technology (International Foundation for Telemetering, 1988-10)
      The existing Mission Control and Computer Center at JPL will be replaced by the Space Flight Operations Center (SFOC). One part of the SFOC is the Local Area Network-Based Distribution System. The purpose of the Local Area Network (LAN) is to distribute the processed data among the various elements of the SFOC. The SFOC LAN will provide a robust subsystem that will support the Magellan launch configuration and future project adaptations with the following capabilities: * A proven cable medium (Ethernet) as the backbone for the entire network, with capability for migration to a fiber optics backbone in the future. * Choice of hardware components that are reliable, varied, and supported by companies that are following the growth path of the ISO model (OSI Standards). * Insure a reliable and maintainable network for SFOC-supported projects. * Accurate and detailed documentation of the LAN, valuable for fault isolation and future expansion of the network. * Proven network monitoring and maintenance tools.
    • Spaceborne Recording Systems for the Space Station Era

      Muench, Jerry; Odetics, Inc. (International Foundation for Telemetering, 1988-10)
      A detailed review of spaceborne magnetic tape recorder technology from the late 1970s to the Space Station era is presented. Background information indicates the oft maligned space tape recorder has continued to demonstrate improving reliability since the marginal performances throughout the 1960s. Specifically, the SPOT recorder is reviewed in technical detail to show evolution through LANDSAT 6 and 7 versions, JERS-1, and finally the proposed ultimate version for Space Station/EOS. Enabling technologies include active tape tracking, magnetic recording head advances, and extensive use of ASIC devices to reduce the EEE piece part count. Suitability of the proposed Space Station/EOS recorder technologies for even more advanced future applications are discussed with data rates to 1 Gbps and storage capacities to 1 X 10¹² bits.
    • Spacecraft Telemetry Tracking State of the Art and Trends

      Mayer, Gerhard; DFVLR Applied Data Syst. Div. (International Foundation for Telemetering, 1988-10)
      Telemetry Tracking is a method of obtaining trajectory information regarding any flying body such as an aircraft, missile, satellite, balloon or a deep space probe which signals or "marks" its flight position by an electromagnetic radiating source. In a trade-off of costs it is an attractive way to combine Telemetry, Tracking and Command (TTC) facilities into one integrated system on board a spacecraft and with the ground receiving and tracking facilities. The present state of the art of Distance Measuring Equipment (DME) and Angle Measuring Equipment (AME) integrated with telemetry systems is reviewed. The further development will be mainly stimulated by the technology evolution of frequency and time reference sources, microwave components and information processing systems. An attempt is made to analyse which way the growth of technology will influence various system parameters.
    • Static RAM Data Recorder for Flight Tests

      Stoner, D. C.; Eklund, T. F. F.; Sandia National Laboratories (International Foundation for Telemetering, 1988-10)
      A static Random Access Memory (RAM) data recorder has been developed to recover strain and acceleration data during development tests of high-speed earth penetrating vehicles. Bi-level inputs are also available for continuity measurements. An iteration of this system was modified for use on water entry evaluations.
    • A Survays On Fading Channel Over West - Java Area for Flight Test Radio Telemetering Purposes

      Soelaiman, Adi Dharma; Pudjiastuti, Rina; Indonesian Aircraft Industry Ltd. (International Foundation for Telemetering, 1988-10)
      This paper discusses one approach to determine a characteristic of West - Java's air and ground segment as a block-box to accomodate radio waves propagation, especially in L-band ranges, by evaluating both the topographical data and radio reception pattern as measured from ground based telemetry receiving-end system. All the measured signals are random and assumed to be stationair and ergodic. In order to characterize the channel for polarization diversity reception, some statistical analysis are applied to the signal strength measured of both - RHCP and LHCP components of 1531 MHz propagated waves as transmitted fr om NC212-200 PK-NZJ-aircraft. Some computer calculated correlograms of measured data are shown herewith, it is focused for a certain radio corridor at radial 265E relative to the ground based receiving antenna. More over some curves of predicted multipath gain factor are also presented to gain more theoretical back ground. When this paper is written, a further field experiments on the matter concerned is beeing conducted.
    • A Symmetric Telemetry Diversity Combiner System

      Busch, Charles E.; Fernandez, Jose M.; Scientific-Atlanta, Inc. (International Foundation for Telemetering, 1988-10)
      Phase-tracking discontinuities produced by switching transients in the usual Master/Slave telemetry diversity combiners under deep-fade conditions, can create data loss in modern, phase-modulated telemetry systems. This paper presents an innovative, dual-channel diversity combining system that overcomes this deficiency, has improved phase noise performance, and maintains full optimal ratio combining for PM, FM, and PSK modulated PCM telemetry. This is accomplished by a symmetric architecture that does not rely on either of the two input channels as a master reference to which the other is phase locked. The new design has the added advantage that the phase noise of a weak master channel is not superimposed on a stronger slave channel.
    • System Aspects of Digital Video Telemetry

      Deutermann, Alan R.; Randall, Neil C.; Delta Information Systems, Inc. (International Foundation for Telemetering, 1988-10)
      This paper describes a completely integrated digital video telemetry system and analyzes several critical aspects of that system. The typical video network may consist of video source signals on the ground as well as airborne while the receive site is usually ground based. Examples of system issues which will be described and analyzed are listed below. * Multi-mode operation: It is likely that a single receive site must be able to rapidly switch between video sources having different bit rates and modes of operation. One technique to achieve this capability will be presented and discussed. * Error sensitivity: It is important that the coding compression technique be resilient to transmission errors. Techniques to achieve this robustness for both synchronization and data signals will be discussed. * Data Multiplexing: From a system point of view, it is extremely efficient to multiplex other digital signals (e.g. audio, IRIG time code) with the video signal to form a single stream for encryption and transmission. A particularly efficient multiplex technique will be presented. * Diagnostics: Video telemetry systems are more effective when they contain carefully designed built-in diagnostics. Advanced concepts for both board-level and system-level diagnostics will be presented.
    • A System Conforming to the New IRIG Standard for Processing MIL-STD-1553 Data

      Payne, David; O'Brien, Mike; Fairchild Weston Systems Inc. (International Foundation for Telemetering, 1988-10)
      The typical aircraft development program of the 1990's will use multiple airborne MIL-STD-1553 Data Busses to provide control of the avionics subsystems. These programs have created a need to process data from these busses in a standard format. This format is proposed for Chapter 8 of the IRIG-106 document. This paper describes EMR's MIL-STD-1553 PROCESSING SYSTEM to acquire and process data in accordance with this new standard. This fully integrated and already available system consists of two basic elements: * An All-Bus Instrumentation System(ABIS). * A Ground Processing Station (GPS). The ABIS monitors the MIL-STD-1553 airborne communications busses, and formats all data in a standard IRIG serial PCM stream suitable for on-board recording and/or real-time transmission on a radio link. Each ABIS will handle all data from one to eight busses. The GPS provides both real-time display and post-flight processing of data captured by the ABIS.
    • Tape Certification Today and in The Future

      O'Sullivan, Tony; Book, Harold; BOW Industries, Inc. (International Foundation for Telemetering, 1988-10)
      The advent of high density digital recording has required the development of sophisticated tape certification equipment which allows the user to test tape for dropouts at his actual system bit packing density and to clean and program wind tapes with the same equipment. By using two sets of reproduce heads with dual threshold and duration controls tapes can be graded as to their suitability for use with HDDR systems or far less exacting analog applications.
    • Telemetry Chart Recording Via Direct Digital Link

      Smith, Grant M.; Alexander, James H.; Astro-Med, Inc. (International Foundation for Telemetering, 1988-10)
      Mission safety and cost-efficiency concerns have resulted in a resurgence of interest in real-time strip chart recorders. But conventional recorder technologies require inordinate maintenance and daily calibration. Attempts at strip chart emulation involving costly dedicated microcomputers and CRT's have failed, because the chart itself is not real-time, a basic requirement. The concept of an inexpensive, direct digital link to a telemetry processing computer (VAX, e.g.) is discussed. A thorough examination of real-time monitoring of critical, non-repeatable data is presented. Objectives: An automated, turn-key telemetry data system. Reduce the routine maintenance required by conventional recording systems; eliminate the need for digital-to-analog converters (DAC's); and improve the efficiency of range personnel and the integrity of recorded data.
    • Telemetry Data Processing: A Modular, Expandable Approach

      Devlin, Steve; Aydin Monitor Systems (International Foundation for Telemetering, 1988-10)
      The growing complexity of missle, aircraft, and space vehicle systems, along with the advent of fly-by-wire and ultra-high performance unstable airframe technology has created an exploding demand for real time processing power. Recent VLSI developements have allowed addressing these needs in the design of a multi-processor subsystem supplying 10 MIPS and 5 MFLOPS per processor. To provide up to 70 MIPS a Digital Signal Processing subsystem may be configured with up to 7 Processors. Multiple subsystems may be employed in a data processing system to give the user virtually unlimited processing power. Within the DSP module, communication between cards is over a high speed, arbitrated Private Data bus. This prevents the saturation of the system bus with intermediate results, and allows a multiple processor configuration to make full use of each processor. Design goals for a single processor included executing number system conversions, data compression algorithms and 1st order polynomials in under 2 microseconds, and 5th order polynomials in under 4 microseconds. The processor design meets or exceeds all of these goals. Recently upgraded VLSI is available, and makes possible a performance enhancement to 11 MIPS and 9 MFLOPS per processor with reduced power consumption. Design tradeoffs and example applications are presented.
    • Telemetry Processing - Realtime to Postflight

      Quesenberry, Dave; Reed, Gary; CSC Network Systems Division (International Foundation for Telemetering, 1988-10)
      The Test Support Facility Integrated Flight Data Processing System (TSF IFDAPS) has recently been developed and installed for the Air Force at Edwards AFB. The TSF IFDAPS incorporates a number of new capabilities designed to satisfy today's advanced requirements for high performance and flexible telemetry processing. This paper describes some of the advances accomplished by the TSF IFDAPS.
    • Trends in Telemetry Systems

      Strock, O. J. (Jud); Fairchild Weston Systems, Inc. (International Foundation for Telemetering, 1988-10)
      This tutorial is an examination of trends in telemetry systems as we approach the 1990s. . . a look at where we are, and where we appear to be headed in the near future. Historically, the typical change in our technology is brought about by one of three conditions. First, users demand performance improvements in order to facilitate their analysis of test programs. Second, manufacturers make performance improvements because continuing advances in component technology enable them to offer improved products for telemetry applications. Third, developments in non-telemetry applications, both hardware and software, are adapted to our needs by system designers. We will see the results of all three conditions as we look at trends in telemetry systems.
    • uDACS Micropackaged Data Acquisition and Control System

      Sodini, Gregory L.; SCI Technology Inc. (International Foundation for Telemetering, 1988-10)
      The miniaturization of Aerospace Systems, has created a demand for effective, compact, lightweight, and power efficient General Purpose Stand-Alone Flight Computers, as well as Command, Data Handling and Control Systems, that maintain High Reliability, Full Redundancy, Radiation Hardness, Explosive Processing Speed, Rapid Throughput, and High Accuracy. The innovative design techniques used in the uDACS (Micropackaged Data Acquisition and Control System) offer a unique and comprehensive solution to this quandary.
    • The Use of Databases in Telemetry Processing Systems

      Massing, James E.; Fairchild Weston Systems Inc. (International Foundation for Telemetering, 1988-10)
      The amount of information necessary for a computer to setup and process data through a telemetry system is increasing rapidly, The complexity and number of telemetry formats often requires a variety of front-end setups to be kept in the computer. Also, as hardware preprocessors become more common, there is a need to maintain in the computer all information used to direct real-time processing of individual parameters. The need for storage of those setups and parameter definitions, and rapid retrieval of this information, has led to the use of databases in well-designed telemetry systems.
    • Utilization of Real Time Digital Strip Chart Emulation (RTDSCE) Concepts

      Halsey, Tim; Brimbal, Michel; Grottenthaler, Gary; Gould Incorporated (International Foundation for Telemetering, 1988-10)
      "Real Time Digital Strip Chart Emulation", a paper presented in the 1987 ITC Proceedings is reviewed for continuity and the digital techniques applicable to range data display are expanded upon. The paper seeks to present the process of recording telemetered signals in the RTDSCE data management scheme. Direct hardware interfacing is discussed with emphasis on automation and manpower reduction. Time code display and various mass storage possibilities are explored. The merits of video monitoring and the workstation concept during playback are evaluated.
    • Video Compression Standardization Issues

      Stephens, Charles R.; Premmco (International Foundation for Telemetering, 1988-10)
      This paper discusses the development of a standard for compressed digital video. The benefits and applications of compressed digital video are reviewed, and some examples of compression techniques are presented. A hardware implementation of a differential pulse code modulation approach is examined.
    • Video Compression Techniques

      Cilke, Tom; LORAL/CONIC (International Foundation for Telemetering, 1988-10)
      This paper will attempt to present algorithms commonly used for video compression, and their effectiveness in aerospace applications where size, weight, and power are of prime importance. These techniques will include samples of one-, two-, and three-dimensional algorithms. Implementation of these algorithms into usable hardware is also explored but limited to monochrome video only.
    • VLSI High Speed Packet Processor

      Grebowsky, Gerald J.; Dominy, Carol T.; NASA Goddard Space Flight Center (International Foundation for Telemetering, 1988-10)
      The Goddard Space Flight Center Mission Operations and Data Systems Directorate has developed a Packet Processor card utilizing semi-custom very large scale integration (VLSI) devices, microprocessors, and programmable gate arrays to support the implementation of multi-channel telemetry data capture systems. This card will receive synchronized error corrected telemetry transfer frames and output annotated application packets derived from this data. An adaptable format capability is provided by the programmability of three microprocessors while the throughput capability of the Packet Processor is achieved by a data pipeline consisting of two separate RAM systems controlled by specially designed semi-custom VLSI logic.
    • Wideband High Performance Telemetry Tracking and Data Reception System

      Bedford, Cary C.; TT & C Systems; Datron Systems Incorporated (International Foundation for Telemetering, 1988-10)
      A 5 meter diameter wideband polarization diversity Telemetry Tracking System has been developed for Eglin Air Force Base. A single solid state feed, with no moving parts, provides autotrack and data reception in the 1435-1540 MHz and 2200-2400 MHz bands. The system consists of three tracking antennas, each mounted on separate 75 foot high towers. The antennas feature continuous rotation capability in azimuth and remotely controlled stowing mechanisms. A common console containing test equipment, multicouplers, patch panels, RF switching, boresight source and control equipment is interfaced with the three (3) tracking antennas, receiver combiner systems, and boresite antenna. The complete system features total integration of state-of-the-art feed/RF, tracking, and control system electronics with a highly versatile sub-system of telemetry receivers, combiners, RF, and wideband high level video distribution equipment.