• AIR FORCE SATELLITE CONTROL FACILITY ARCHITECTURE

      Konopasek, L. K.; The Aerospace Corporation (International Foundation for Telemetering, 1984-10)
      This paper presents an architectural overview of the Air Force Satellite Control Facility (AFSCF) with emphasis on the network’s Remote Tracking Stations (RTSs). The AFSCF originated twenty-five years ago, and has evolved into a global satellite service network. This worldwide network is composed of twelve RTSs, located at seven geographically dispersed locations, and a Satellite Test Center (STC) at Sunnyvale, California. The AFSCF provides real-time telemetry, tracking, and commanding (TT&C) service to Department of Defense (DoD) spacecraft and launch vehicles. In response to changing DoD space support requirements, the AFSCF and its RTSs have grown through expansion and modernization of their tracking, data processing, and communication capabilities. What follows is, then, a review of this network evolution; a description of today’s, stations, their capabilities and limitations; an introduction of planned improvements; and a view of what will be required for satellite service in the future.
    • REMOTE TRACKING STATION (RTS) MODERNIZATION PROGRAM

      STUART, FLOYD R.; Sunnyvale Air Force Station (International Foundation for Telemetering, 1984-10)
      This paper presents the need for the modernization of the AFSCF RTSs. The system design concept set forth features an automated RTS under remote control by an external control center. The automated RTS objective is to achieve a common ground station configuration for the AFSCF which facilitates interoperability, internetting, and future growth; and to reduce ground station operations and support costs.
    • THE FUTURE OF THE REMOTE TRACKING STATION

      Stell, David W.; The Aerospace Corporation (International Foundation for Telemetering, 1984-10)
      The Air Force Satellite Control Facility’s Remote Tracking Stations, as they are presently configured, are encountering several factors which will change their future viability and utility. These factors include examples such as survivability and endurability requirements, estimates of future Satellite Control Network loading, dependence on foreign ground stations, and life cycle cost. Probable future Remote Tracking Station configurations are discussed in view of these factors.
    • CANADIAN FORCES PCM TELEMETRY PROCESSING AND DISPLAY SYSTEM

      Glenesk, Major L.B.; Marriott, Captain J.L.; Aerospace Engineering Test Establishment, CFB Cold Lake (International Foundation for Telemetering, 1984-10)
      Canadian Forces (CF) flight test facilities were recently updated to support testing of the CF-18 aircraft by the development of a new ground based PCM telemetry processing and display system (TPADS). Additional enhancements to this system are currently underway, or being considered, to further improve flight test mission control and data processing functions and produce a system capable of meeting CF flight test requirements into the 1990’s.
    • INTRODUCTION OF S-BAND TELEMETRY TRACKING SYSTEMS AT THE CHURCHILL RESEARCH RANGE (CRR) DURING 1983/84

      Dawson, Brian F.; Canada Centre for Space Science (International Foundation for Telemetering, 1984-10)
      S-Band Auto-track systems were introduced at CRR in January 1983 and each consists of a 3.0 metre reflector, pedestal, servo drive, antenna controller with dual RF channels, double ended feed, low noise amplifier and downconverters to P-Band frequencies. The S-Band requirements and restrictions at CRR will be discussed, and the factors restricting launch acquisition explained. Angle data (AZ/EL) is transferred in real-time to an HP 9845 processor for quick-look and later trajectory analysis purposes plus comparison with Interferometer/Tone Ranging and Command Systems (TRACS) data. This presentation is intended to provide a basic familiarity with S-Band facilities and capabilities now available to Range Users at CRR.
    • ANALYTICAL STUDY ON BIT-SYNCHRONIZATION PROBLEMS IN A CODED COMMUNICATION SYSTEM

      Ng, Wai-Hung; The Aerospace Corporation (International Foundation for Telemetering, 1984-10)
      Many bit-synchronization techniques in digital communications depend on bit transitions for successful operation. In this paper, we first categorize the four main sources of generating transitionless signals. Then we describe general properties of channel coding and explain that, by injecting a well-selected detectable error pattern into the transmitted and coded signal, this bit transitionless problem can be eliminated without any additional bandwidth penalty. Finally, examples in both block code and convolutional code are selected for illustrating this simple but useful application.
    • A LOCALLY PROGRAMMABLE/NONVOLATILE WORD SELECTOR FOR DISPLAY OF TAGGED TELEMETRY DATA

      Duffy, Harold A.; Naval Weapons Center (International Foundation for Telemetering, 1984-10)
      The introduction of Data Compressors into the NWC Telemetry Ground Station has created the opportunity to circumvent usage of data distribution patch panels. An array of Word Selectors can be used to capture telemetry data parameters by tag identification for display on chart recorders. Design goals in the development include: independent operation, resident program storage, variable word length handling, and accommodation of nonstandard data formats. A prototype has been constructed and tested.
    • 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.
    • COMPANDER CIRCUITS IMPROVE TRANSDUCER DATA QUALITY

      Rieger, James L.; Naval Weapons Center (International Foundation for Telemetering, 1984-10)
      AC-coupled transducers such as crystal accelerometers and microphones can produce a large dynamic range of signals, but the expected level from such devices in an actual test situation may be difficult to predict. Use of compander circuits intended for telephone and “hi-fi” systems can increase dynamic range and accuracy of the signals from such devices and reduce noise at low levels and clipping at the top of the range. Companders (COMPressor plus expANDER) can be used in single- or double-ended modes depending on the data requirements. They do introduce predictable artifacts of their own, but many of these can be removed.
    • 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.
    • FLASH RADIOGRAPHIC INSTRUMENTATION FOR SMALL CALIBER BALLISTIC STUDIES

      Webster, Edwin A., Jr.; U.S. Army Armament R & D Center (International Foundation for Telemetering, 1984-10)
      This paper reviews the basic design and general characteristics of a family of standard flash x-ray systems, used for obtaining small caliber ballistic data, ranging from 100-kV to 2.3-MV peak output voltage. The design emphasizes control and repeatability of x-ray output and reliability in the field. Different system configurations and types of output radiations are available to optimize fit to various applications. Selected applications are briefly discussed to illustrate equipment use and performance.
    • Distributed Instrumentation A ‘Mini-’ Range Instrumentation System

      Heyser, Bob; Army Materiel Test and Evaluation (International Foundation for Telemetering, 1984-10)
      In a test environment where several projects are vying for time for their test program, how do you support the programs who are waiting their turn in line? Or the program which only wants telemetry support in his assembly area, and doesn’t want to pay for the entire range? The answer is a ‘mini-’ range instrumentation facility without the expensive tracking and relay systems. Distributed Instrumentation allows for 1) Project dedicated support; 2) Project unique support; and 3) Project favorable costs. Distributed Instrumentation is a network of instrumentation capabilities which can be catalog selected and integrated into a project friendly system, and can support the project’s particular requirements and time schedule.
    • AN ELECTRICALLY-SMALL MONOPOLE PHASED ARRAY ANTENNA FOR WIDE BAND APPLICATIONS

      Sheng Y. Peng; Pfaff, Gerald A.; Teledyne Micronetics (International Foundation for Telemetering, 1984-10)
      An electrically-small, lightweight, and low RCS (radar cross-section) Monopole Array Antenna has been developed for wide band application. The monopoles were printed on a low dielectric constant (εr = 2.3) substrate and fed by a modified meanderline microstrip feed structure, with quarter-wavelength stubs to improve feed efficiency. The operational frequency is from 0.65 to 2.0 GHz. The physical size of the monopole array measures only 0.125 wavelength in height. The weight is about 0.3 pounds. A four-element subarray was built and tested. Its overall physical size is 2.5 inches in height by 10 inches in length by 24.4 inches in width. The measured gain and pattern data are presented, as well as the low RCS property and many applications of the monopole array.
    • THE STEERABLE LUNEBURG LENS AS A COMMUNICATION LINK ANTENNA

      Higgs, James A.; Worth, Richard A.; Teledyne Micronetics (International Foundation for Telemetering, 1984-10)
      A review of the Luneburg Lens and its use as an antenna aperture is presented. Also discussed are methods of electromechanical and electronically switchable operation along with design criteria. Applications in the field of data link communications and telemetry are suggested and the performance of several operational systems are outlined.
    • S-BAND CIRCULARLY POLARIZED MICROSTRIP PHASED ARRAY

      Coombs, Dennis L.; Ball Aerospace Systems Division (International Foundation for Telemetering, 1984-10)
      A highly efficient circulary polarized S-band microstrip planar phased array is described. The array is: • Electronically steerable in elevation and azimuth • Highly efficient at the subarray level (greater than 60 percent) • Well matched for active impedance with a near cos a scan performance • Designed for optimum G/T performance • Designed to have a thin profile but be extremely strong The microstrip elements, phase shifters and combiner network are described in detail and their operation is explained.
    • A COMPUTERIZED CHECK-OUT SYSTEM FOR TRANSDUCERS IN NUCLEAR POWER PLANTS

      Brandt, Axel; SCS Technische Automation und Systeme GmbH (International Foundation for Telemetering, 1984-10)
      A computerized check-out system for recording and analysis of test data of transducers in nuclear power plants is described. The system is composed of two subsystems, the STATIONARY and the MOBILE SYSTEM. The STATIONARY SYSTEM fulfills all necessary administrative functions, allows data analysis, reporting, and longterm storage of test data. The MOBILE SYSTEM is the test device. It is set up by three components - controller unit, interface, and microcomputer - the whole being assembled on a moveable wagon which makes on site testing of the transducers possible. The number of MOBILE SYSTEMS is selectable according to user needs and environmental condititions. Data transport between the systems is accomplished via magnetic tape cartridges or online by a standardized communication line.
    • A NEW CALIBRATION CONCEPT FOR INSTRUMENTATION TAPE RECORDERS

      Spurr, Robert N.; Honeywell Test Instruments Division (International Foundation for Telemetering, 1984-10)
      A new calibration concept for instrumentation tape recorders which insures consistent data quality is presented. This technique utilizes a single composite signal for complete amplitude and phase equalization of direct reproduce data electronics. In addition, the method permits equalization for tapes recorded with analog or saturation record electronics, and also permits calibration at different reproduce tape speeds from a single recorded preamble. The composite signal description and block diagram of the generation-measurement equipment are presented along with system test results.
    • 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.
    • THE WHITE SANDS MISSILE RANGE TELEMETRY VALIDATION SYSTEM (TVS)

      Avila, G. Edwardo; Rice, William A.; White Sands Missile Range, NM (International Foundation for Telemetering, 1984-10)
      The purpose of this paper is to briefly discuss the evolution and history of the White Sands Missile Range (WSMR) Telemetry Validation System (TVS). Ongoing development of an automated TVS is discussed in terms of system philosphy, configuration, and operation.
    • BENEFITS OF POLARIZATION DIVERSITY RECEPTION

      Berns, K. L. (Ken); SETAC Inc. (International Foundation for Telemetering, 1984-10)
      The utilization of polarization diversity reception to compensate for pattern irregularities of telemetry transmitting antenna systems is examined. Statistical analyses are conducted to compare signal strengths of the orthogonal polarization components of transmitted radio waves. Probability density functions and cumulative distribution functions of transmitting antenna gain patterns are calculated. These statistical functions are used as the basis for comparisons of the quality of recovered signals with and without polarization diversity capabilities at the receiving station. It is concluded that polarization diversity can be used to significantly improve signal quality in the presence of antenna pattern irregularities.