• NEW ANTENNA FEED REVITALIZES SPACE SHUTTLE TRACKER AT NASA EDWARDS

      Wrin, John W.; Sullivan, Arthur; NASA-Ames Research Center; Electro-Magnetic Processes, Inc. (International Foundation for Telemetering, 1984-10)
      A twelve foot diameter Single-Channel Monopulse Tracking System, relegated to slaved backup status at NASA Edwards, was rejuvenated to support research flights for Ames Dryden Research Center and for tracking orbital passes of the Space Shuttle and Shuttle landings both at Edwards and at White Sands. Status has been upgraded to that of Stand- Alone Telemetry Tracking System. A significant factor in this upgrading was the replacing of the Single-Channel Monopulse feed with a RADSCAN feed developed by EMP. Previously the system would not autotrack at elevation angles below five (5) degrees. Since modification the system automatically acquires the Space Shuttle when it appears on the horizon and autotracks from approximately two (2) degrees in elevation to touchdown. This, virtually unattended. This paper describes the RADSCAN and Single Channel Monopulse concepts individually and then makes a detailed comparison between the two.
    • HIGH-POWER, SOLID-STATE AMPLIFIER

      Hom, H.; McMaster, R.; Sanders, B.; ITT Gilfillan (International Foundation for Telemetering, 1984-10)
      Because of recent advances in both bipolar and divider/combiner technologies, solid-state amplifiers can now be configured to operate at high power levels through L-, S- and Cband frequencies. This paper describes both module and divider/combiner technology developments that are required to achieve amplifier peak powers of 200 kW at L-band, 70 kW at S-band, and 30 kW at C-band. The feasibility of this performance throughout these frequency ranges has been demonstrated in the Antenna/Microwave Lab at ITT Gilfillan.
    • COMMAND, CONTROL AND COMMUNICATIONS (C³) FOR THE DEFENSE METEOROLOGICAL SATELLITE PROGRAM

      Williams, Stephen L., Captain; Kinney, Thomas W.; USAF Space Division; Harris Government Information Systems Division (International Foundation for Telemetering, 1984-10)
      This paper describes the architectural philosophy and the interaction between the DMSP C³ ground system and the strategic and tactical users of DMSP imagery data. Some of the ongoing activities relating to future enhancements and survivability are also explored. At the present time, the ground systems Satellite Operations Center (SOC) has been installed at Offutt Air Force Base, Nebraska, and is supported by the two remote Command Readout Stations (CRS’s) at Fairchild Air Force Base, Washington, and Loring Air Force Base, Maine. All commanding, planning and telemetry processing is centralized at the SOC. Backup and redundant subsystems and communications services are provided for reliable operation plus there is an internet with the Air Force Satellite Control Facility (AFSCF) for early orbit and anomaly support.
    • OPTIMUM PRESENTATION OF SATELLITE TELEMETRY DURING SATELLITE ACCEPTANCE TESTING

      Thompson, J. T.; The Aerospace Corporation (International Foundation for Telemetering, 1984-10)
      Telemetry data collected during the several months of satellite acceptance testing are voluminous. These test data should be presented in an optimum fashion to facilitate thorough review, leading to high confidence in the quality of the satellite prior to launch. This paper defines various telemetry data types, discusses an optimum method for presentation of each, and summarizes an actual application of these principles. Comparison with earlier methods is included.
    • A MODULAR, LARGE SCALE, INTERACTIVE TELEMETRY DATA ANALYSIS SYSTEM

      Luten, Robert H.; Computer Technology Associates, Inc. (International Foundation for Telemetering, 1984-10)
      The Test and Evaluation Data Center (TEDC) was originally developed at Lockheed Missiles and Space Company with the objective of providing a data processing facility to support major systems test evaluation. This data center was responsible for the acquisition, reduction (to engineering units), analysis, protection, and management of all (telemetered) test data produced during system integration and test activities. The TEDC was developed as a local area network, consisting of several VAX-11 computers and other commercial off-the-shelf hardware, which could acquire telemetry data at rates greater than 1 Mbps (potentially 4-5 Mbps) and, with rapid turnaround, make it available to a large number of engineering analysts via interactive graphics terminals. This paper discusses the engineering, design, and development of the TEDC, including descriptions of the major algorithms, data structures, and techniques used to optimize its overall performance. Discussion of plans for the evolutionary growth of the system are also included.
    • SPIN RATE AND POSITION MEASUREMENT TELEMETRY SYSTEM

      Richter, I.; Hochman, D. (International Foundation for Telemetering, 1984-10)
      As part of an effort to reduce a projectile’s spin, a telemetry system was developed in order to measure spin rate and position of a given point on a round during flight. The telemetry system consisted of twelve special sensors (sensitive to sun light) which were installed on the shell’s perimeter and an electronic system, that converted the sensors’ analog output into a conventional PCM stream that was transmitted, received, and decoded into position and spin rate. The telemetry system although exposed to very severe environmental conditions such as high G’s, vibration and temperature, operated successfully.
    • TRACKING STATION INTEROPERABILITY

      Krenek, D. A.; The Aerospace Corporation (International Foundation for Telemetering, 1984-10)
      The DoD is focusing considerable attention on interoperability and internetting as effective means of increasing the survivability of space systems. The tracking stations of the various DoD space systems are prime candidates for interoperability and internetting enhancements for two reasons: (1) a belief that the “front ends” of the various ground command and control segments is where the greatest commonality of functions should already exist; and (2) the knowledge of the large existing DoD capital investment in tracking station assets. This paper provides a method for examining the similarities and commonalities among tracking stations and for identifying incompatibilities and differences which, if eliminated, would facilitate interoperability and internetting and, hence, improve the survivability of DoD space systems.
    • A TELEMETRY SYSTEM FOR MEASURING STRESS IN A HIP JOINT PROSTHESIS

      Postal, R. B.; Boreham, J. F.; California Institute of Technology (International Foundation for Telemetering, 1984-10)
      It has been clinically observed that a significant fraction of hip joint implants fail due to mechanical loosening, particularly in younger, more active patients. Design enhancements are hampered by the lack of in vivo data of the actual forces produced on the prosthesis by various recipient activities. This paper describes a telemetry system small enough to fit in the spherical ball joint of a hip joint prosthesis. The system is capable of transmitting sufficient in vivo data to allow reconstruction of major forces through the prosthesis. The design allows for total hermetic enclosure of the electronic parts within the prosthesis which is implanted within the human body. Figure 1 shows 2 engineering model prosthesis assemblies. Input power coupling is provided through a cuff temporarily placed over the area of the device. Telemetry readout from the transmitter antenna, also totally enclosed, allows periodic out-patient checkup and monitoring. In this manner, since no batteries are used, in vivo monitoring of load forces on the prosthesis can be accomplished periodically over a several year period without surgical revision. The data obtained will be used to design stronger implants which will have very low failure rates even when subjected to activities of younger recipients.
    • A METHOD FOR OBTAINING REAL TIME RECOVERY VEHICLE DATA

      Diebel, Dean L.; Recovery Systems Instrumentation Branch (International Foundation for Telemetering, 1984-10)
      In the development and design of parachutes, select data parameters are required for evaluation. These parameters give the designer dynamic information in actual environments providing stress, load, and glide ratio information. At present this information (altitude, rate of descent, total velocity, acceleration, dynamic pressure and attitude), is obtained by the use of space positioning methods. Meterological data, used to calculate some of these parameters, are obtained from rawinsonde balloons which are launched one half to two hours before and after the drop test. Typical combined data accuracies are on the order of plus or minus f ive percent with most of these errors being ascribed to the fact that the weather data is not taken at the time of the test and atmospheric conditions change rather quickly during the morning hours when the tests are typically done. A method has been developed which will measure meterological data real time. Direct measurements are taken via transducers ie. pressure, acceleration, attitude, temperature and humidity. These transducers are combined in the microprocessor circuitry to obtain final data prior to solid state recording or transmission. This paper will describe the methods and justifications for pursuing a different type of data gathering system.
    • SELF BALANCING STRAIN GAGE SIGNAL CONDITIONING FOR THE TRIDENT II (D-5) MISSILE

      Penharlow, David; Aydin Vector Division (International Foundation for Telemetering, 1984-10)
      Strain gage signal conditioning requirements of the Trident II (D-5) Missile offer the instrumentation designer some unusual challenges. Large quantities of strain gages are installed in inaccessible locations of the missile. These strain gage signals require balance adjustment a few seconds after application of power. Traditional strain gage balance techniques were rejected due to the inaccessibility of the units and the time requried for the adjustment. This paper discusses the selected solution to this problem – the Aydin Vector BCA-916 Self Balancing Bridge Conditioning Amplifier. The amplifier assembly achieves high performance in a small package through the use of thick film hybrid technology. The amplifier uses a digital autobalance technique to offset the strain gage unbalance on application of power. The unique design of this signal conditioner fulfills the requriements of the Trident II Missile.
    • PROGRAMMABLE PCM ENCODER

      Poirier, Norman C.; Wheeler, Thomas P.; Department of Electrical and Computer Engineering; Northeastern University (International Foundation for Telemetering, 1984-10)
      This paper will present the concept of a general purpose pulse code modulation (PCM) encoding system which has all the major operating parameters under stored program control. This type of encoder can be used in a large variety of scientific/engineering data gathering applications by simply programming an onboard EPROM to tailor the encoder to the specific mission requirements. Key words: Pulse Code Modulation (PCM), Encoder, Data Acquisition, Parity, Programmable Filter, Multiplexer.
    • STRUCTURED SOFTWARE DESIGN IN A REAL-TIME CONTROL APPLICATION

      DeBrunner, Keith E.; Dyn-Opus, Inc. (International Foundation for Telemetering, 1984-10)
      Software for real-time (time critical) control applications has been shown in military and industry studies to be a very expensive type of software effort. This type of software is not typically addressed in discussions of software architecture design methods and techniques, therefore the software engineer is usually left with a sparse design “tool kit” when confronted with overall system design involving time critical and/or control problems. This paper outlines the successful application of data flow and transaction analysis design methods to achieve a structured yet flexible software architecture for a fairly complex antenna controller used in automatic tracking antenna systems. Interesting adaptations of, and variations on, techniques described in the literature are discussed; as are issues of modularity, coupling, morphology, global data handling, and evolution (maintenance). Both positive and negative aspects of this choice of design method are outlined, and the importance of a capable real-time executive and conditional compilation and assembly is stressed.
    • TRANSIENT SUPPRESSION IMPROVES RELIABILITY OF HIGH POWER AMPLIFIERS

      LEHMAN, WALTER; ELECTRONICS AND OPTICS DIVISION; THE AEROSPACE CORPORATION (International Foundation for Telemetering, 1984-10)
      Intolerably high failure rates were experienced on a number of 1.8 G4z solid state amplifiers used in high power transmitters. Investigations revealed the existence of dangerously high transients on the DC power bus which extends from the power converter in the antenna pedestal to the amplifier located under the feed. Current and voltage requirements were such as to render commercially available transient suppressors, including zener diodes, ineffective. The problem was solved with a shunt regulator which normally draws no current, but effectively clips the transients.
    • SINC- AND SPLINE CURVES SMOOTH DATA FOR PLOTTERS

      Rieger, James L.; Birch, Kent N.; PE/PTBW; Naval Weapons Center (International Foundation for Telemetering, 1984-10)
      Computer programs in BASIC are shown which smooth curves from sampled data for display on a plotter by calculation of interstitial values using spline and truncated sinc functions. A program is shown for reconstruction of frequency-translated sampled data. Accuracy and computational speed of the two algorithms are compared.
    • ASSESSMENT OF METROLOGICAL PARAMETERS BY MEANS OF FIBER-OPTIC SENSORS

      Kist, Rainer; Fraunhofer-Institut für Physikalische Messtechnik (International Foundation for Telemetering, 1984-10)
      Fiber-optic sensors will get their share of the sensor market only if they can be made available at low prices or if they can solve metrological problems that have no suitable solutions within conventional sensor techniques. Since fiber-optic components are in general still high cost items, fiber-optic sensors are not likely to become competitive in this respect within the near future. These sensors do provide, however, important specific advantages such as isolation against high voltage, immunity against electromagnetic fields as well as explosive and/or corrosive environments, possibility of miniaturized and compact packaging of the sensing element, and application within a broad temperature range. Multimode fiber-optic sensors for parameters such as temperature, pressure, level , and refractive index are on the market already or very close to being commercialized. Monomode fiber-optic sensors are not yet on the market due to their more demanding technology and the corresponding higher cost level . They are expected, however to provide at acceptable costs in a forseeable future high precision solutions for metrological tasks under specific conditions (e.g. Sagnac gyroscopes, hydrophones, temperature measurement in a microwave field).
    • ARTS OVERVIEW

      Skinner, Patrick J.; Ford Aerospace & Communications Corporation (International Foundation for Telemetering, 1984-10)
      Modernizing labor intensive Remote Tracking Station (RTS), increasing individual station capacity, and providing interoperable links between three separate Air Force satellite networks are the objectives of the Automated RTS (ARTS) program. (Viewgraph #1, Title/Logo)
    • A MICROPROCESSOR CONTROLLED PARACHUTE DEPLOYMENT SYSTEM

      Turner, Donald G.; Naval Weapons Center (International Foundation for Telemetering, 1984-10)
      In the design and development of parachutes for recovery systems (missile, test vehicle, drone, etc.) there is a need for accurate controls and measurements during testing. Relations between air speed, air density, opening forces, and drag can only be determined in a dynamic environment. Through the use of microprocessors and programming flexibility, parachute design parameters can evaluated. Improved signal to noise characteristics are obtained through error analysis and compensation techniques. The incorporation of microprocessors has become a key element in the accurate control and measurement of parachute design parameters for recovery systems.
    • PREDETECTION RECORDING OF PCM TELEMETRY SIGNALS

      Law, Eugene L.; Pacific Missile Test Center (International Foundation for Telemetering, 1984-10)
      This paper discusses the performance of predetection recording of pulse code modulation (PCM) telemetry signals. The topics discussed include bit rate versus predetection carrier frequency, effects of receiver and demodulator bandwidths on data quality, and demodulation at tape carrier frequencies versus upconversion and demodulation.
    • FIBER OPTIC DIGITAL WIDEBAND COMMUNICATION SYSTEM

      Anderson, Robert B.; Industrial Data Link (International Foundation for Telemetering, 1984-10)
      Industrial Data Link Corporation is presently installing a 3 phase, 30 Km fiber optic voice/data communication system for the Yuma Proving Ground (YPG) in Arizona. This system will provide a backbone communication system for YPG to transmit digital telemetry data and voice circuits between 3 test centers and the Base Dial Central Office. The fiber optic cable is being installed in three different modes; underground (direct burial), duct and aerial. Our proposed paper would cover the following areas: a.) System requirements --data channels (up to 56 Kb/s) --voice channels --future growth (video) b.) System design - component description c.) Installation d.) Test and initial system operation e.) Pictures (slides) and video coverage of system installation to augment the presentation f.) Cost and technical trade-off studies between fiber optic cable and microwave link as the communication medium g.) Cost analysis (ratios) for laying of fiber optic cable, dollars per meter for burial, duct and aerial h.) Summary of state-of-the-art of fiber optic component and predictions of future component/system capabilities for range telemetry applications. i.) The special characteristics of fiber optic cable links as applied to secure telemetry requirements on Government Test Ranges.
    • BALLISTIC RAIL GUN – SOFT RECOVERY TECHNIQUE

      Paduano, Michael J.; Zimmerman, John R.; HQ US Army Armament Research and Development Center (International Foundation for Telemetering, 1984-10)
      The ARDC 155mm Ballistic Rail Gun Test Facility permits the soft recovery of a test projectile and its payload after subjection to an actual gun launch environment. High G hardening and testing of various electronic and mechanical components can be conducted by use of this system. This paper will discuss the conception, operation and reliability of the Ballistic Rail Gun, and the advantages and limitations of its use in qualification of components. Also discussed will be the development of a novel radar technique to determine muzzle velocity for Rail Gun tests, and a separate telemetry system for characterizing in-bore (acceleration) and in-rail (deceleration) environments.