• 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.
    • NAVAL SPECTRUM USE MANAGEMENT AUTOMATION

      Stanley, George V.; Naval Ocean Systems Center (International Foundation for Telemetering, 1981-10)
      The U.S. Navy makes heavy usage of all segments of the electromagnetic spectrum for such diverse applications as communications, control (positioning) of ships and aircraft, target identification, and passive and active electronic warfare. The density of emitters results in a severe electromagnetic interference (EMI) environment in even a moderate size Battle Force. This environment can preclude usage of spectrum resources unless sophisticated spectrum engineering is performed to alleviate the EMI problems and assure system performance. The Navy’s ability to perform this engineering function in the planning stage of a deployment is historically limited by a lack of data, engineering tools, procedures, and trained personnel with sufficient insight into the problem to perform the needed analyses. Similarly, the ability of the afloat spectrum user to re-engineer the spectrum allocation in the face of changing requirements cannot be accomplished during the operational phase of the mission because of the lack of time, experience, and engineering tools. Recent advances in the development of automated spectrum management tools, methodology, and data management have resulted in the fielding of several automated systems which solve parts of the overall spectrum management problem. The lessons learned from these fielded models, in turn, have led to the development of a set of validated operational requirements and architectures and a subsequent system design for an overall Navy spectrum management system. The architecture is based upon a division of functional responsibilities between ashore support activities performing area-wide management (ashore and afloat), and afloat users managing the actual assigned spectrum with a Battle Group. The SUMS system will have the ability to optimally and efficiently solve large sets of EMI, system performance, and spectrum use engineering problems. The prototype of the system will be fielded during 1982-83 for both ashore area-wide and afloat elements.
    • NAVY ENVIRONMENTAL DATA DISTRIBUTION

      WOOLDRIDGE, FRANCIS R.; NAVY SPACE SYSTEMS ACTIVITY (International Foundation for Telemetering, 1981-10)
      The distribution of environmental data by the Navy Oceanography Command to support worldwide fleet operations is discussed. The fact that these operations are being conducted from platforms which are under sea, on the ocean surface and in the air, forms the basis for a variety of unique distribution methods. The organization of the Naval Oceanography Command is shown along with the fleet units operating with geophysics personnel attached. Methods of distribution include data sources to support the generation of numerical products and tactical operations. Fleet communications links are described including the data processing systems being installed at shore stations and onboard ships.
    • NAVY SATELLITE COMMUNICATIONS

      Captain Newell, John W.; Naval Electronic Systems Command (International Foundation for Telemetering, 1981-10)
      The significant advantages of quality and capacity, offered by Satellite Communications are now fully recognized throughout the Navy and DOD. Efficient use of the vital UHF SATCOM links is evolving as challenging command and control requirements are being met through micro-processor based system engineering. Extension of Navy SATCOM developments into the SHF and EHF portion of the spectrum offers further advanced capabilities to meet increasing tactical and strategic C³ requirements including anti-jam and LPI wartime capabilities. This paper reviews the several Navy SATCOM programs in being and in development to provide space age improvements in communications for the Fleet.
    • NETWORK SUPPORT OF TDRSS

      Smith, Cassius C.; TRW White Sands Ground Terminal (International Foundation for Telemetering, 1981-10)
      The Tracking and Data Relay Satellite System (TDRSS) is controlled by a local computer network of nine Digital PDP-11/70s and a Univac 1100/82. Distributed processing of specific software tasks provides for high-speed response to time critical loop support, as well as increased reliability and flexibility of the overall system. Man-machine interface, spacecraft monitor/control and computer failover is supported by the distribution of tasks to specific computers within the network. Altogether, the network support of TDRSS makes possible tremendous increases in capability over conventional satellite ground stations.
    • THE NEW ESA TT&C GROUND STATIONS

      Uhrig, H. K.; European Space Agency (International Foundation for Telemetering, 1981-10)
      The European Space Agency is used to refer to its telemetry, telecommand and tracking stations as ground stations because they do not cover only TT&C as used in the world of telecommunication satellites. At present ESA is erecting a new generation of ground stations. They are not on newly opened sites. Partly they are self-contained stations and partly they are major replacements and upgradings of subsystems of existing stations. The design of all of these stations follows a common modular concept by breaking it down into subsystems which correspond to the functional tasks a station has to perform. The organisation of this paper is as follows : Section 2 describes the task of the ground station, Section 3 is concerned with its system breakdown, Section 4 outlines those modules which are common to all new ground stations, Section 5 lists briefly the sites and the stations found there and Section 6 tries to provide an outlook on the forthcoming development.
    • NEXT GENERATION COMMUNICATION SATELLITE PROGRAM FOR THE DEPARTMENT OF DEFENSE

      Birch, J. N.; Birch Associates, Inc. (International Foundation for Telemetering, 1981-10)
      The DoD is planning a new Mil Sat Com Program, one which will provide the U.S. Military with a capability to maintain the peace or if need be, fight a war.
    • NOVA AND GEOSAT COMPUTERS

      Perschy, James A.; Johns Hopkins Road (International Foundation for Telemetering, 1981-10)
      Two computers, utilized on-board the Navy satellites NOVA, launched in May 1981, and GEOSAT, to be launched in early 1984, are reviewed. The NOVA computer is an extension of the TRIAD design presented at the 1972 Government Microcircuit Applications Conference. The NOVA computer is the third generation digital data handling system for the Navy Transit Navigation Satellites. Covered in this paper is the computer architecture, hardware design, and relation to other satellite systems. The design of the NOVA computer software and its in-orbit performance is covered in a companion paper. The NOVA computer is an integral part of the on-board data handling system. It formats the Transit navigation message, stores and analyzes telemetry, and executes commands to extend the autonomous operation time of the satellite. The GEOSAT computer is a signal processor for a satellite born radar altimeter. It is an extension of the SEASAT-A design presented at the 1977 JBIS Symposium on Computer Techniques for Satellite Control and Data Processing. Its principal design feature is the incorporation of a microprocessor. The GEOSAT computer performs return signal acquisition, range tracking, receiver gain control, calibration, ocean wave height estimation, telemetry formatting, and command decoding. This paper gives a brief description of the GEOSAT computer functional performance, hardware, and software.
    • ON-BOARD PROCESSING FOR ATTITUDE CONTROL OF APPLE

      Mirugesan, S.; Rao, C. Kameswara; Shanmugam, C.N.; Goel, P.S.; ISRO Satellite Centre (International Foundation for Telemetering, 1981-10)
      APPLE, India’s first three axis stabilised communication satellite, was launched by the ARIANE launcher on June 19,1981. The communication payload operates in C-band (4-6 GHz) and facilitates experiments in communication technology and its applications. Attitude and Orbit control System (AOCS) of APPLE, whose on orbit performance is satisfactory despite the non deployment of one of the solar panels, is briefly described. Various functions on the Attitude Control Electronics (ACE) are described with details on processing schemes for Pulsewidth Pulse Frequency Modulator, Yaw error computation using hybrid SINE convertor, Magnetic torquer control and Thruster selection. Further, future trends in onboard processing for communication satellites are highlighted.
    • ON-BOARD PROCESSING FOR THE NOVA SPACECRAFT

      Whisnant, J. Miller; Jenkins, Robert E.; Utterback, Harry K.; The Johns Hopkins University (International Foundation for Telemetering, 1981-10)
      A major hardware change to the TRANSIT Navy Navigation Satellite System (NNSS) is underway. A new generation of satellites called NOVA are being built which have onboard a general purpose minicomputer, high precision clock, orbit adjustment system (OATS), and disturbance compensation system (DISCOS). This paper describes the software and processing for the on-board computer. The software is a system of interrupt driven, real-time programs which perform various data management and control functions and allows great flexibility in the operation of the satellite. In addition to loading special programs and data and dumping specified regions of memory, data management includes loading and then retransmitting navigation message data and collection of both telemetry (TM) data and DISCOS thruster firing data. Through its interface with the spacecraft TM and command systems, the on-board computer also serves as a powerful control device, especially in the orbit adjust phase immediately after launch. It has already been demonstrated with a previous version of these satellites that this highly flexible software system can be quickly reconfigured after launch to recover from failures to other satellite hardware systems. Also described in this paper are other satellite subsystems which interact with the flight computer and the system of ground support computers and software.
    • ONBOARD PROCESSING FOR COMMUNICATIONS SATELLITES

      Davies, R.S.; Chethik, F.; Kota, S.L.; Ford Aerospace & Communications Corporation (International Foundation for Telemetering, 1981-10)
      Future satellite networks may include satellites that provide multiple uplink and downlink coverage antenna beams together with signal processing subsystems. Where the number of earth terminals is large and the traffic is diffuse, efficient methods for routing signals need to be developed. This paper addresses the switching and routing processes for both long term connections (stream traffic) and short messages (burst traffic). Onboard routing appears most efficient for burst traffic where as stream traffic is best handled by means of a ground based traffic controller. An integrated control system concept is suggested together with access and multiplex formats to accommodate mixed traffic.
    • 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.
    • PAYLOAD TECHNOLOGIES FOR THE EUROPEAN COMMUNICATION SATELLITES IN THE 90’s

      COIRAULT, R.; European Space Agency (International Foundation for Telemetering, 1981-10)
      New communication services are developing quite fast in Europe. At long term they will certainly be handled mostly by a terrestrial network with satellite links to complement when it is more cost effective. Future satellite payloads shall thus be designed to meet new demands especially as regards growing and fluctuating traffic patterns. Unfortunately, meaningful forecasts cannot be made, as yet. In this context, a payload technologies assessment exercise is presently being carried out by ESA. The scarcity of data concerning the expected traffic has been compensated for by the introduction of “pilot missions”. Although hypothetical they correspond to various scenarios and provide the required system background. This paper outlines the pilot missions characteristics and reviews the critical payload technologies which are concerned and ought to be developed in order to meet the next decades challenges. The “pilot missions” include: an extensive provision of specialised services in the 11/14 GHz frequency range, a very high capacity service at 20/30 GHz for a videocommunication application and a global service at L-Band for aeronautical, land and maritime mobiles. The associated technologies focus essentially on antennas and signal processors. The antenna sub-system must generate high gain spot beams. Low sidelobes requirements are also an essential characteristic in view of an efficient frequency re-use. Large reflectors will be necessary, with possibly a deployment in orbit. Complex and active feed networks will be implemented. On board signal processing represents another major break-through in payload technologies. RF switching matrices could be the baseline for the specialized services at 11/14 GHz. Regeneration with routing performed at baseband will be an essential feature of the 20/30 GHz application. At L-Band a data bus concept is an attractive approach.
    • THE PCM DROPOUT INDICATOR - A USEFUL DEVICE

      Hahn, J. C.; Rockwell International (International Foundation for Telemetering, 1981-10)
      During test and checkout of Space Shuttle systems, data is transmitted from test sites to processing centers via overland transmission lines and communication satellite. Loss of data (dropouts) may take place and can be attributed to a malfunction at the transmitting end, the receiving end or the transmission path itself. Before effective trouble shooting can begin, the cause must be isolated to a particular area or unit. The PCM Dropout Indicator is one of the devices used for this task.
    • PERFORMANCE BOUNDS FOR ANALOG SIGNAL ENCRYPTION

      Gersho, Allen; Dept. of Electrical & Computer Engineering (International Foundation for Telemetering, 1981-10)
      It is sometimes desirable to perform analog scrambling on an analog signal rather than digitizing the signal and performing digital encryption and transmission. Analog signal encryption is usually assumed to offer only a very limited degree of security. However, it is in fact possible to achieve perfect secrecy (just as is obtained with the one-time pad, for example) in encrypting an analog signal. The price paid for perfect secrecy is an inevitable degradation in the quality of the recovered analog signal. Under the constraint of perfect secrecy, the minimum possible degradation can be specified, at least in principle. This minimal degradation is a decreasing function of the key size for a fixed length message or key rate for an ongoing message. This bound on performance is determined by the rate distortion bounds for optimal digitization of the analog message.
    • PHASE NOISE MEASUREMENT SYSTEMS

      Lance, A. L.; Seal, W. D.; Labaar, F.; TRW Electronics and Defense (International Foundation for Telemetering, 1981-10)
      Phase noise is the term most widely used to describe the characteristic randomness of frequency. Automation of phase noise measurements has been developed with satisfactory results using two techniques referred to as the two-oscillator technique and the singleoscillator technique. Measurements are performed in the frequency domain using a spectrum analyzer which provides a frequency window following the phase or frequency detector. State-of-the-art systems include system modifications for cross-spectrum measurements and techniques used to improve the noise floor characteristics of the delay line FM discriminator in order to measure single sources which have very low phase noise characteristics.
    • PLANNING THE AFSCF OF THE FUTURE

      Carroll, James T.; The Aerospace Corporation (International Foundation for Telemetering, 1981-10)
      This presentation describes the Air Force Satellite Control Facility (AFSCF) planning cycle by use of decision package sets that will be incorporated in the DoD portion of the President’s budget. Major AFSCF projects reviewed include Data System Modernization; Remote Tracking Station (RTS) Modernization; Shuttle Support; Advanced Telemetry, Tracking, and Command; Transportable RTS; and the NASA Tracking Data Relay Satellite (TDRSS) interface with the AFSCF. Zero based budgeting using decision packages determine project priorities and approval levels. The benefit and task description of AFSCF major projects is described for the years 1983 through 1987. Long range priorities through the year 2000 are summarized.
    • PREPROCESSING IN TODAY’S TELEMETRY COMPUTER SYSTEM

      Hildebrand, Graham; Sangamo Weston (EMR Telemetry) (International Foundation for Telemetering, 1981-10)
      An increasing number of processes are being moved from the host computer to a versatile, smaller front end preprocessor. This paper discusses the reasons for preprocessing and presents a general purpose preprocessor. Use of the preprocessor in mapping MIL 1553 Multiplex Bus data is described as well as the more routine tasks of data merging and identification, compression, engineering units conversion, array forming, and data sorting.
    • PRESSURE RESISTANT BULKHEAD PENETRATORS FOR FIBER OPTICS IN DEEP OCEAN APPLICATIONS

      Cowen, Steven J.; Naval Ocean Systems Center (International Foundation for Telemetering, 1981-10)
      This paper describes results obtained at the Naval Ocean Systems Center, San Diego, under Independent Exploratory Development funding. The objective was to develop a robust, fully-demountable, high pressure penetrator design suitable for coupling light signals transmitted by optical fiber elements in an undersea cable operated at high ambient hydrostatic pressure into an electronics package or manned space. The feasibility of constructing such penetrators utilizing Graded Refractive INdex (GRIN) rod lenses as combination pressure barriers and imaging devices was demonstrated. Prototype realizations exhibited excellent optical throughput performance and readily survived in excess of 10,000 psi pressure differential as well as tolerating a wide temperature range. The design lends itself to hermetic construction for applications requiring no vapor diffusion over long mission durations. Such devices exhibit excellent potential for satisfying SUBSAFE requirements for manned submersible applications.
    • A PROGRAMMABLE-SIGNAL CONDITIONING PULSE CODE MODULATED TELEMETRY ENCODER

      ECKSTEIN, HOWARD M.; MICROCOM CORPORATION (International Foundation for Telemetering, 1981-10)
      The development of variable format airborne PCM data acquisition systems has generally been predicated upon advances in the field of solid state memory device technology. The introduction of Electrically Eraseable Programmable Read Only Memory (EEPROM) devices has generated renewed interest in the design of fully programmable PCM encoders. This paper will describe the evolution of one such micro-miniature PCM encoder system incorporating the following features: ∙ Complete Frame Format Program Capability ∙ Software Controlled Single Ended/Differential Input Program Capability ∙ Individual Sample - Gain/Offset Scaling Capability ∙ Hard Wire Program/Erase/Program Capability ∙ Variable Word Resolution ∙ Small Size