• International Telemetering Conference Proceedings, Volume 17 (1981)

      International Foundation for Telemetering, 1981-10
    • DIGITAL DATA IN VIDEO PROCESSING SYSTEMS

      Morse, Bob A.; BELL TECHNICIAL OPERATIONS (International Foundation for Telemetering, 1981-10)
      Digital information in video systems is an expanding field. The use of digital video equipment is continuously being examined and updated at USAYPG. There are fully operational systems currently being used by BELL TECH. OPS at the proving ground. I shall cover some of the uses and capability of the systems as well as the individual pieces of equipment in the systems
    • THE PARTICULATE NOISE POWER SPECTRUM OF A MAGNETIC TAPE RECORDER/REPRODUCER

      Hedeman, Walter R., Jr.; Law, Eugene L.; Pacific Missile Test Center (International Foundation for Telemetering, 1981-10)
      This paper presents a theoretical derivation of the noise power spectrum of a magnetic tape recorder/reproducer. The theoretical results are shown to be in good agreement with experimental data.
    • AN ARCHITECTURAL DESIGN OF AN FDMA/TDM BASEBAND PROCESSOR FOR 20/30 GHZ SATELLITE COMMUNICATIONS SYSTEM

      Jean, P. N.; Neal, W. R. (International Foundation for Telemetering, 1981-10)
      An architectural design of a baseband processor to provide on-board processing for a 20/30 GHz communications satellite is presented. The operation of this processor is explained in some detail. Major assumptions, considerations and goals that shaped the design of the baseband processor are identified and discussed. Since a primary benefit of on-board processing is flexibility, systems employing a processing satellite system will need versatile network protocols. A two-level network protocol that permits users to specify various parameters of their message links and to use different routing protocols on a message-by-message basis is presented here.
    • UPLINK TELEMETRY: A LOGICAL EXPANSION OF FLIGHT TEST DATA ACQUISITION SYSTEM CAPABILITIES

      Venorsky, G. W.; McDonnell Aircraft Company (International Foundation for Telemetering, 1981-10)
      A reliable telemetry uplink, operating simultaneously and compatibly with normal downlink telemetry, will provide the flight test community with a versatile and flexible means of managing airborne data acquisition systems. This paper recommends incorporation of telemetry uplink capabilities into data acquisition systems employed in aircraft developmental flight testing. Potential applications are discussed, including: • In-flight real-time, reformatting of an airborne data system. • Time code synchronization. • Merging of external data sources into onboard data streams. • Presentation of ground processed data to the pilot via cockpit displays. • In-flight programming of flight-test-peculiar equipments, e.g. flutter excitation controllers. Reduced downlink telemetry bandwidths, higher mission productivities, and decreased pilot workloads are expected benefits. The results of an ongoing, McDonnell Aircraft Company, (MCAIR), funded (IRAD*) uplink development and evaluation program are presented, including the ground-based segments integrated into an autotracking antenna system. Alternatives also are discussed for integration of telemetry uplink systems into normally used test facilities, contractor and government operated.
    • 30 GHZ IMAGE ENHANCED MIXER “FRONT-END” FOR SPACEBORNE LOW NOISE RECEIVER USAGE

      H. DeGruyl; Ng, E.; Okean, H.C.; Steffek, L.J.; Tallerico, T.; LNR Communications, Inc. (International Foundation for Telemetering, 1981-10)
      A Ka-band low noise “front-end” currently under development for ultimate spaceborne receiver deployment, consists of a 27.5-30 GHz image-enhanced mixer integrated with a 3.7-6.2 GHz FET low noise IF amplifier and driven by a self-contained 23.8 GHz phaselocked LO source. The image enhanced mixer, designed for 5 dB overall “front-end” SSB noise figure, utilizes a balanced pair of in-house high quality GaAs Schottky mixer diodes embedded in a composite waveguide/TEM “crossbar” balanced mixer structure possessing inherent mutual RF/LO isolation. The three stage FET IF amplifier, implemented in a single-ended microstrip configuration, has, in a preliminary breadboard, exhibited 24.5 ±0.5 dB gain and 1.5 to 2.4 dB noise figure over the 3.7-6.2 GHz band. The LO source, consisting of a C-band high power FET VCO, phase locked to an external 500 MHz crystal reference, and driving a C-to-K band varactor quadruplet, will provide up to 40 mW LO drive at 23.8 GHz.
    • HUMAN FACTORS IN TELEMETRY SYSTEM DEVELOPMENT

      Chafin, Roy L.; Jet Propulsion Laboratory (International Foundation for Telemetering, 1981-10)
      Telemetry systems are becoming increasingly sophisticated and complex. At the same time, economics is forcing the use of fewer and less technically skilled operators. This paper suggests including human factors in systems design to better match system characteristics with operator characteristics. It discusses why human factors should be included in system design. It defines and discusses human factors. Human factors specialists are the practitioners of the art and science of human factors design. The art is in the experience and insight of the human factors specialists, and the science is in his knowledge of the theoretical foundations of human factors. His knowledge and experience is applied to telemetry system design at several places in the design effort. Early in the requirements phase, human factors specialists identify the human factors issues and establish man-machine interaction philosophy and human factors design guidelines. During the design phase they assist the designers on the detailed design of the man-machine interface. After and even during the design phase, the human factors specialists evaluate the design with theoretical analysis. After delivery, they evaluate the system in its operating environment using real operators.
    • TDRSS GROUND SEGMENT PERFORMANCE

      Matchett, M.W.; Government Communications Systems Division (International Foundation for Telemetering, 1981-10)
      About 150 racks of fully-automated equipment provide tracking, user traffic transmission and reception, simulation, and verification services for users of NASA’s Tracking and Data Relay Satellite System (TDRSS). Installation of this equipment in the White Sands Ground Terminal Facility is now complete and final testing is nearly complete. This paper describes the implementation and performance of that portion of the ground segment equipment provided by Harris. Major equipment groups described are 1) antennas, 2) user traffic link forward (transmit) equipment, 3) S-band single-access return (receive) equipment, 4) K-band single-access return equipment, 5) multiple-access RF equipment, 6) range and range-rate equipment, 7) user spacecraft simulation equipment, and 8) system verification equipment.
    • A 16 WATT Ku BAND GaAs FET POWER AMPLIFIER

      Huang, Thomas K.; Rhodes, Richard A.; Mehta, Jayanti; Hughes Aircraft Co. (International Foundation for Telemetering, 1981-10)
      An experimental power amplifier using GaAs FETs was built and tested. This power amplifier delivered 16 watts of RF output power in mid Ku-Band. It employed 88 GaAs FET devices and demonstrated 40 dB of gain with 12% DC to RF efficiency. The design considerations of power output, efficiency, bandwidth, size and thermal description are discussed from the viewpoint of potential space application. Also discussed are combining philosophy and package layout. Actual experimental results are presented.
    • THE TRACKING AND DATA RELAY SATELLITE SYSTEM: AN OVERVIEW

      Davis,Malcolm G., Jr.; TRW Defense and Space Systems Group (International Foundation for Telemetering, 1981-10)
      The Tracking and Data Relay Satellite System (TDRSS) is a shared service system supplying leased communication and tracking services to NASA and commercial Advanced Westar channels to Western Union and the American Satellite Company. An overview of the TDRSS design is presented. The space segment, consisting of four geosynchronous satellites, is described including launch. The spacecraft is described with emphasis on the communications payload covering both the NASA TDRSS and Advanced Westar equipment. The ground terminal located at White Sands, New Mexico, serves as the interface between the four TDRSs and up to 32 user satellites simultaneously for data transmission, tracking and spacecraft control via NASA’s communication network (NASCOM). The functions and characteristics of the White Sands ground terminal are presented.
    • MICROWAVE TRANSISTOR POWER AMPLIFIERS

      Balshem, Harold; Microwave Semiconductor Corp. (International Foundation for Telemetering, 1981-10)
      The availability of both silicon bipolar and gallium arsenide field effect microwave power transistors has been responsible for the development and manufacture of relatively high power, reliable, solid state amplifiers from L-band to K-band. Pulse power of a kilowatt at 1 GHz and 100 watts at 3.5 GHz are representative of what is practically achievable in pulse amplifiers while powers of 50 watts at 1.6 GHz, 6 watts at 6 GHz and 1 watt at 13 GHz are similarly representative of CW amplifiers. State-of-the-art development has currently achieved 1 watt at 21 GHz from a single device. Transistor characteristics, design considerations and performance of power amplifiers will be described.
    • 20 GHz MULTISTAGE FET POWER AMPLIFIERS

      Sokolov, V.; Saunier, P.; Bennett, R.C.; Lehmann, R.E.; Texas Instruments Incorporated Central Research Laboratories (International Foundation for Telemetering, 1981-10)
      A GaAs FET power amplifier module operating in K-band is described. The module has integral input and output WR-51 waveguide ports and incorporates a pair of low-loss waveguide to microstrip transitions. Single-stage and multi-stage microstrip FET amplifiers are fabricated on individual copper carrier blocks incorporating in-package impedance matching. Six packaged amplifiers are cascaded to achieve a 0.5 W, 30 dB gain amplifier module operating over the 17.7-20.2 GHz band.
    • A METEOROLOGICAL COMMAND AND CONTROL SYSTEM

      P. L. Greening; Kinney, T. W.; Shaw, T. R.; HARRIS CORPORATION (International Foundation for Telemetering, 1981-10)
      There are many functions required to command, control and maintain the health and welfare of a meteorological satellite and acquire payload sensor data in a real time scenario. This paper describes the functions and performance of a specific meteorological command/control and telemetry processing system. Further, this paper describes the communications networks which link the various command/control, telemetry, and user ground stations together. A description of the user sensor data is also presented.
    • ADVANCED 14/12 AND 30/20 GHz MULTIPLE BEAM ANTENNA TECHNOLOGY FOR COMMUNICATIONS SATELLITES

      Chen, C.C.; TRW Defense and Space Systems Group (International Foundation for Telemetering, 1981-10)
      This paper discusses recent TRW advances in communications satellite antenna technologies for the 14/12 and 30/20 GHz bands. The 14/12 GHz antenna system provides 15 or more high gain, low sidelobe spot beams for contiguous coverage of the CONUS for point-to-point communications, or four contoured time zone beams for direct broadcast service. A 2-meter offset reflector has been built and tested to demonstrate the frequency reuse and beam isolation capabilities of the antenna. The 30/20 GHz antenna system provides 10 to 20 fixed beams for large volume traffic trunking service and six independently scanned beams for customer-premise-service within the CONUS. A proofof- concept model antenna for proving the technology feasibility is currently under development.
    • NATO TEST AND EVALUATION RANGE STAVANGER, NORWAY

      Dahl, Ernest A.; NATO PUTTS System (International Foundation for Telemetering, 1981-10)
      The NATO Test Range at Stavanger, Norway permits cold environment testing of NATO Systems, common TLM data processing for many types of missiles, with both ship/shore control as well as evaluation. Figure 1 shows the location.
    • TT & C SYSTEM FOR AT&T TELSTAR 3

      Moore, Joe S.; Ohlrogge, Larry D.; Hughes Aircraft Company (International Foundation for Telemetering, 1981-10)
      The first of three TELSTAR 3 satellites will be launched in mid 1983. Prior to this time, a Telemetry Tracking and Control system will have been installed to track and command the satellites during transfer orbit and will continue these tasks when each satellite is in it’s working orbit. This system consists of the Satellite Control Center (SCC) and the Primary Satellite Control Earth Station (PSCES), co-located at Hawley, Pennsylvania. In the event of unforeseen circumstances, the alternate satellite control center and earth station at Three Peaks, California, would be capable of performing the on-station Telemetry, Tracking, and Command operations for all three TELSTAR 3 satellites. Each location has redundant computer systems which are capable of all telemetry and command processing for three spacecraft. Only the Hawley site has the capability for tracking during transfer orbit by using the 13 meter full-motion antenna. This 13 meter antenna also houses the computercontrolled test equipment that will perform initial in-orbit testing of all three satellites, as well as normal testing throughout the life of the satellites. During transfer orbit, remote tracking station services will be provided by stations which are not part of the AT&T system. Data collected by the remote stations will then be sent to the SCC at Hawley for use in determining attitude and orbit. The second and third launches are scheduled for Mid 1984 and 1985, respectively.
    • THE TECHNOLOGIES OF AUTONOMOUS SPACECRAFT MAINTENANCE

      Elowitz, Murray L.; Wong, Bill C.; TRW Space and Technology Group (International Foundation for Telemetering, 1981-10)
      Autonomous spacecraft maintenance (ASM) is the term used to describe the capability of a spacecraft to perform its maintenance functions without frequent, regular ground support and interactions. This new spacecraft attribute is needed to enhance the survivability and availability of our satellites, as well as to reduce operational support costs. This paper explains the concept of ASM as it has evolved. Generic requirements are given and explained for a latter 1980's capability. Spacecraft architectural changes are required, involving a mixture of technology adaptation and advances. Technology developments required to meet the requirements are identified and assessed. Significant advances are needed in system and subsystem technology areas to create a posture for building an ASM capability. With WWMCCS increasing reliance on spacecraft for both communication and sensor data, the issues of ASM are of vital importance to this community.
    • SOFTWARE IN DRONE CONTROL

      Shaver, Robert L.; Sandia National Laboratories (International Foundation for Telemetering, 1981-10)
      High performance multi-use drones require complex control capability. Distributing the communications, control and navigation functions among different microprocessor systems connected in a network improves performance and reliability. Assembly language provides the means of optimizing time critical functions of communications and I/O control, which high level languages, such as PASCAL, ease development of mission management requirements. The use of real-time operating systems (RTOS) permits co-processing of a variety of functions in overall drone operation management. The RTOS is a software “bus” providing communications network for modules. Functions and modules are assigned priorities, enabled or suspended as needed to perform mission operational requirements via the RTOS.
    • THEORETICAL AND PRACTICAL ASPECTS OF OPTIMIZATION IN FINITE WORD-LENGTH DIGITAL SIGNAL PROCESSING

      Pollara-Bozzola, F.; Yao, K.; Univ. of California (International Foundation for Telemetering, 1981-10)
      We consider a general class of digital signal processing problems in which some sytem parameters restricted to some finite set of values are selected based on the minimum meansquare error criterion. This class of problems are relevant in the design of modern communication, radar, and antenna array systems under finite word-length con-constraints. Linear problems allowing infinite precision values are given by the classical Wiener solutions. However, under the finite word-length constraints, optimum solutions can be obtained in principle by using techniques from integer quadratic programming problems. Practical solutions obtained in this manner, such as from the branch-and-bound algorithm, usually use a large amount of active computer memory space and thus are not applicable to real-time on-board processing situations. In this paper, we shall consider various theoretical and practical aspects of exhaustive search algorithms over shrinking sequences of constrained regions known to contain the desired optimum solution. Properties and bounds on the number of points to be searched as well as specific system problems shall be presented.
    • S BAND FLUSH ANTENNAS FOR THE SHUTTLE ORBITER

      Waineo, Douglas K.; Ellis, Haynes; Rockwell International Corporation (International Foundation for Telemetering, 1981-10)
      Two telemetry and communications antennas for the Shuttle Orbiter are described. Each antenna is circularly polarized and flush mounted under the thermal protection tiles. The quad antenna provides two beam positions selected by an electromechanical switch, and uses two cavity backed crossed dipole elements radiating through reduced size circular apertures called irises. The GPS/hemi antenna covers three frequencies, with 160E cone coverage at two L-band frequencies and 120E cone coverage at S-band.