• DESIGN OF A DATA ACQUISITION SYSTEM BASED ON THE DECOMMUTATION OF AN EMBEDDED ASYNCHRONOUS DATA STREAM WITHOUT PRIMARY AND SECONDARY FRAME SYNCHRONIZATION

      Kvasnak, Michael A.; Koonmen, James P.; Grajeda, Vivian L.; Space Technology Directorate (International Foundation for Telemetering, 1991-11)
      The use of embedded asynchronous data streams is becoming a popular means of expanding existing telemetry systems and acquiring subsystem data. In such systems, synchronization between the primary and secondary system(s) clocks is usually considered a prerequisite. The Phillips Laboratory has developed a software/hardware approach to the problem of decommutating an embedded asynchronous data stream without primary and secondary frame and clock synchronization. The methodology employed is easily implemented and adapted to many system configurations, and represents a low-cost option in the acquisition of subsystem data. More importantly, the use of such a system greatly reduces the amount of systems integration effort required to incorporate multiple subsystems into a host telemetry system.
    • DESIGN PARAMETERS FOR A FM/FM SYSTEM

      Carden, Frank; New Mexico State University (International Foundation for Telemetering, 1991-11)
      Design parameters for a FM/FM telemetry system are determined in terms of the IRIG specifications for proportional bandwidth channels. Three mathematical models used by designers of the above processes are extended and compared. That is, FM multitone models are used to establish the relationship between frequency deviations, modulation indices, signal-to-noise and IF bandwidth for the IRIG channels. Since spectral efficiency and signal quality are of major importance, a goal of the design is to have a minimum IF bandwidth, while fixing as large as possible the values of the modulation indices for the subcarriers modulating the carrier in order to achieve as large as needed output signal-to-noise ratio.
    • A DIGITAL DEVICE FOR FAST ACQUISITION OF PSEUDO-RANDOM CODE

      Gu, X.M.; Wang, J.P.; Yuan, S.J.; Li, W.S.; Zhang, Y.J. (International Foundation for Telemetering, 1991-11)
      A digital device for rapid acquisition of the initial phase of PN code has been implemented. The principles and results of the experiment are introduced in this paper. The m PN code is modulated on IF with BPSK type. The cycle of PN code P=255 chips. The rate of PN code R=5.1 × 10 chips /s. The IF is not acquired. The shift in Doppler 6 frequency f is within l-4KHz. In these conditions, the phase of PN code can be acquired d within 3 ms and the error of sychronization is less than 0.5 chip.
    • DOUBLE DENSITY RECORDING ACQUISITION AND PLAYBACK

      Roth, Paul; DATATAPE, INC. (International Foundation for Telemetering, 1991-11)
      This paper discusses signal performance of longitudinal Double Density acquisition recordings made an flight recorders and reproduced on a single laboratory ground station recorder. it includes comparisons with standard bandwidth recording signal performance.
    • A DSP IMPLEMENTED DIGITAL FM MULTIPLEXING SYSTEM

      Rosenthal, Glenn K.; Metraplex Corporation (International Foundation for Telemetering, 1991-11)
      Recent advancements in high-speed Digital Signal Processing (DSP) concepts and devices permit digital hardware implementation of relatively high-frequency signal processing, which formerly required analog circuitry. Systems utilizing this technology can provide a high degree of software programmability; improved reproducibility, reliability, and maintainability; immunity to temperature induced drift errors; and compare favorably in cost to their analog counterparts. This paper describes the DSP implementation of a software programmable, digital frequency multiplexed FM system providing up to 4 output multiplexes, containing up to 36 subcarrier channels extending up to 4 MHZ, and accommodating modulating frequencies up to 64 kHz. System overall design goals and the implementation of these goals are presented.
    • THE EVOLUTION OF AFSCN TELEMETRY SIMULATION SYSTEMS

      Dessling, R.W.; Lockheed Technical Operations Company (International Foundation for Telemetering, 1991-11)
      The Air Force satellite control capability was started in the late 1950s to support command and control of orbiting spacecraft. A need to train and certify ground support personnel as well as to validate equipment configurations soon became evident. Ground personnel would have to know how to generate satellite contact plans, establish connectivity between the satellite and telemetry display terminals, analyze satellite telemetry data, and transmit commands to execute the contact plans. They would have to learn specific ground systems capabilities, satellite design information, and approved command and control procedures. This presentation will review the evolution of telemetry simulation systems as they apply to systems test, personnel training and evaluation. Included will be a discussion of the ground and satellite systems, and how system upgrades and changing operations concepts have fostered the development of telemetry simulators. In describing the next generation of AFSCN simulation systems, this paper will highlight the important part they play in validating system configuration and in personnel training.
    • EVOLUTION OF THE DOD GLOBAL SPACE TEST CAPABILITY

      Grogan, James L., III; Fricks, Robert E. (International Foundation for Telemetering, 1991-11)
      This paper is an overview of progress toward a more formalized military space test range capability. It reviews the motivation for a space test function, relates history which has led to the contemporary space test operation, scopes existing space test pursuits and projects a direction for future activity. Its intent is to baseline the status of the current space test program and to present one vision for its future evolution.
    • EXPERT ANALYSIS OF TELEMETRY DATA

      Delatizky, Jonathan; Morrill, Jeff; Lynch, Thomas J., III; Haberl, Karl; Bolt Beranek and Newman Inc. (International Foundation for Telemetering, 1991-11)
      We describe FAES, a knowledge-based system for postprocess interpretion of telemetry data obtained from in-water tests of the Torpedo MK48 ADCAP and recorded on tape in a telemetry format. The system is designed to automate a diagnostic application in fleet operations. A generic software solution provides the infrastructure for customization through application-specific knowledge representation. Pattern recognition provides a feature-extraction layer between the raw data and an expert system, and gives domain experts a natural and comfortable representation. Use of features abstracted from the raw data greatly reduces the complexity of encoding the rules that describe the behavior of the system under investigation. This allows the experts – not the system programmers – to control the resulting software. The approach has led to development of a system which accurately determines the cause of shutdown in torpedo tests and which will be extended to the full range of diagnostics now done manually. A slightly modified system is being used to support torpedo proofing by automating comparisons of recorded data with the weapon specification and alerting engineers to violations.
    • THE FABLE OF “REAL-TIME” TELEMETRY DATA MOVEMENT

      Gustin, Thomas W.; SYSTRAN Corp. (International Foundation for Telemetering, 1991-11)
      This paper presents an exciting new concept in real-time information distribution that can be easily integrated into existing and future telemetry reception and data dispersal systems. After briefly examining the evolutionary path and various perceptions of the concept “real-time”, a variety of techniques are explored in achieving the expedient movement of real-time information. Many non-telemetry application environments are now using real-time shared-memory networking techniques to obtain large, highspeed integrated sharing of common information. The phenomenal results are partially attributable to high reliability, extremely low latency, and ease of use. This paper attempts to present various telemetry applications and scenarios with descriptions of benefits achieved by simply changing existing data movement techniques to those using shared-memory networking techniques.
    • FARADAY CUP SYSTEM CONTROL LOGIC ON THE WIND SPACECRAFT

      Mavretic, Anton; Konstantinidis, Anastasios; Gergin, Emile; Zhou, Runde; Boston University (International Foundation for Telemetering, 1991-11)
      A satellite-mounted instrument has been developed to measure the energy spectrum of the solar proton flux in the solar wind. The instrument consists of a sensor --- the Faraday Cup, an analog signal processing chain, a high voltage modulator and a digital section. This paper presents the digital section designed and built in our laboratory which functions well to (a) interface with the main processor, (b) to provide the logic signals with proper timing to the analog circuitry, (c) to deliver the necessary bit pattern to the high voltage modulator, (d) to provide the calibration mode control signals when necessary, and (e) to synchronize the sequence of events at the begining of every spacecraft rotation. As with all space projects primary concerns beyond the logical functionality consistes of circuit power consumption, instrumental mass, radiation tolerance levels, stability with respect to temperature, and relative ease of component procurement. The NASA WIND laboratory spacecraft that will carry the experiment is due to be launched in December of 1992 and eventually come to park in an orbit at the first Lagrangian point.
    • FDDI AS AN EMERGING STANDARD FOR TELEMETRY SYSTEMS

      Taylor, Gene; Vista Controls Corporation (International Foundation for Telemetering, 1991-11)
      Various high performance fiber optic networks have been in existence and available now for over 10 years. Virtually all of them, until recently, have been designed around the “better idea” of some single company or engineer, and therefore were or became expensive, proprietary systems, with limited support, and limited or no growth potential. Many benefits were still realized by the users in spite of that; primarily in the areas of increased bandwidth, improved security, and the capability to have data transmission over long distances. However, after 5 years of continued development and refinement, the American National Standards Institute (ANSI) X3T9.5 committee has nearly completed acceptance and final approval of the Fiber Data Distributed Interface (FDDI) specifications. The new FDDI standards have already evidenced a tremendous and eager acceptance by the end user community, and are clearly destined to replace Ethernet as the most prevalent network media. FDDI also offers additional benefits specifically of interest to the telemetry market, and therefore represents an ideal Local Area Network (LAN) technology towards which any TM installation should migrate.
    • FREQUENCY DOMAIN EFFECTS OF LOW RESOLUTION DIGITIZATION

      Law, Eugene L.; Pacific Missile Test Center (International Foundation for Telemetering, 1991-11)
      There is a requirement to digitize certain wide-band analog signals in telemetry applications. Typically, an analog-to-digital converter (ADC) with eight or more bits of resolution is used. The resulting signal requires a much larger transmission bandwidth than the original analog signal. The frequency domain information is of primary interest for many applications. In these cases, there are several methods for minimizing the transmitted bandwidth. One method is to perform fast fourier transforms (FFTs) on the signals and only transmit information about the largest signals. The disadvantages of this approach include: relatively long time delay before transmission, resolution bandwidth fixed when FFT performed (unless phase information is also transmitted), and extra complexity in the telemeter. This paper will discuss some effects of minimizing the transmitted bandwidth by quantizing to a small number of bits. The performance will also be compared with analog frequency modulation (FM). Measured performance will be presented for four different input signals and one-, three-, and eight-bit quantization. These signals are amplitude modulation, angle modulation, sum of sine waves, and frequency sweep. The test setup is shown in figure 1. The analyses presented in this paper were performed using either fast fourier transforms (FFTs) or a Kay DSP Sonagraph. The FFT length was 1024 points and a Hann (cosine) window was used. The analysis hardware used for these tests has an analog input, therefore, all digitized signals were converted to analog signals before analysis. The signals were low pass filtered before analysis to minimize aliasing in the analysis and display process.
    • A GENERIC OBJECT-ORIENTED DESIGN FOR A RADIO FREQUENCY SIMULATION IN A SPACE TELEMETRY AND COMMAND ENVIRONMENT

      Policella, Joseph; CAE-Link Corporation (International Foundation for Telemetering, 1991-11)
      In a generic telemetry simulation the overall fidelity of the simulation is largely based on the simulated vehicle’s On-Board-Systems (OBS) engineering models that drive the generation of the telemetry. Also, the actual transfer of data between the simulated vehicle and control center depends on the ability of the Radio Frequency (RF) OBS to acquire and process the RF links thus resulting in a Acquisition of Signal or Loss of Signal (AOS/LOS) determination. The simulated RF links are a function of the communications OBS models, and the communications environment models. The communications OBS models are responsible for propagating the RF signal. Since the RF link analysis is highly integrated into the characteristics of the communications equipment and environment models, RF link software needs to be constantly redeveloped as communications equipment models change, fidelity is added, or multiple links are created. However, by using a generic objectoriented design, RF link software can process any number of differing links based on the RF characteristics of the propagated wave. As a result, the communications equipment model software can be changed to reflect possible design changes without having to rewrite the RF link software thus allowing reuse of existing code.
    • GLOBAL POSITIONING SYSTEM (GPS) FOR THE ARMY’S AIR DEFENSE OPERATIONAL TESTING

      Parra, Mario Z.; McIntyre, Robert G. (International Foundation for Telemetering, 1991-11)
      The Office of the Under Secretary of Defense for Research and Engineering recognized the potential advantages of a GPS-based range tracking system. As a result, the Range Applications Joint Program Office (RAJPO) was established. (1)The RAJPO was formed to develop a family of NAVSTAR GPS range equipment for the tri-service national test range community. The Air Defense Artillery Test Directorate (ADATD) has supported the RAJPO in the potential use of GPS-derived time, space, and position information (TSPI) in operational testing environments.
    • GLOBAL POSITIONING SYSTEM TELECOMMAND LINK

      Alves, Jr., Daniel F.; Alpha Instrumentation and Information Management (International Foundation for Telemetering, 1991-11)
      The Global Positioning System of satellites and pseudosatellite ground stations (GPS) is designed to provide very accurate Time, Space, and Position Information throughout the entire world. It is also being used to provide such information to unmanned vehicles operating on test ranges throughout the United States, as a replacement/ adjunct for tracking radar as well as a form of guidance. What is proposed in this paper, for which a patent has been applied, is that the existing L-Band RF link carry command information, when required, as well as TSPI information.
    • GPS: THE LOGICAL TOOL FOR PRECISION TRACKING IN SPACE

      Hoefener, Carl E. (International Foundation for Telemetering, 1991-11)
      As we develop more space vehicles, a pressing requirement emerges to provide precision tracking information. This need for exact time and space-position information (TSPI) persists whether developing and testing space weapons or locating the precise position of intelligence-gathering satellites. Because this is a worldwide tracking requirement, the use of conventional tracking techniques such as radar is precluded. Fortunately the Global Positioning System (GPS) is now in place and can provide the tracking information required. GPS offers two techniques for tracking space vehicles. A GPS receiver can be installed on the vehicle to determine the position that is then relayed to a ground terminal, or a GPS frequency translator can be used to compute the vehicle position at the master groundsite. Since both techniques have been proven satisfactory, the specific tracking requirement determines the method selected. For the flight tests of the Exoatmospheric Reentry-Vehicle Interceptor Subsystem (ERIS), the GPS frequency translator technique is used. A GPS frequency translator is installed on the target (a reentry-vehicle launched on a Minuteman from Vandenberg), and a translator is also installed on the ERIS, which is launched from Meck Island in the Kwajalein Atoll. The GPS frequency translator approach was chosen for these tests for a variety of reasons, the most important of which were the limited instrumentation space on the target and interceptor, the extreme dynamics of the interceptor, the tracking accuracy required, and the range at which the operation must be tracked. For the tracking of orbiting satellites, a GPS receiver can be flown on the satellite with its derived position information continuously stored. This data can then be dumped as the satellite passes over a selected groundsite.
    • GREATER THAN 3 MHZ MULTICHANNEL A/D CONVERSION ON A SINGLE VME BOARD

      JARYNOWSKI, ROBERT J.; New Mexico State University (International Foundation for Telemetering, 1991-11)
      A VME computer can be used to provide the basis for a telemetry data processing station. Using “off-the-shelf cards” the designer is able to build up a front end that meet several of the data processing requirements. The ease in interfacing to the VME bus also provides a convenient platform for the development of highly specialized interfaces requiring programmable control. The results are a low-cost highperformance system that is easily expandable as needs and/or technology grow. Based on this strategy, the Physical Science Laboratory (PSL) at New Mexico State University developed a multichannel high-speed analog-to-digital converter (ADC) assembly on a single VME board. The design approach used at PSL to develop the VME-based ADC is discussed in an effort to describe both developments in analog-to-digital conversion integrated circuits and the use of a VME CPU to control them for data processing purposes.
    • A GUI BASED SYSTEM FOR AUTOMATIC CONSTRUCTION OF ENGINEERING MODEL SOFTWARE FOR COMMAND RESPONSE AND TELEMETRY GENERATION

      Parlanti, Joe; Pinkerton, Ronnie; CAE-Link Corporation (International Foundation for Telemetering, 1991-11)
      There exists today, numerous off-the-shelf hardware solutions for the generation of simulated telemetry data streams. The ability to rapidly develop engineering models to drive the data contents of the telemetry is restricted by the lack of contemporary CASE tools. This paper presents an object-oriented Graphical User Interface (GUI) approach to generation of mathematical models in order to reduce the time required for model generation to a fraction of today’s development time, eliminate the need to write substantial amounts of software, and allow reuse of model objects in a manner consistent with the GUI cut, paste, and copy metaphors.
    • GULF RANGE DRONE CONTROL UPGRADE SYSTEM MOBILE CONTROL SYSTEM

      Wagner, Steven M.; Goodson, John H.; General Electric Government Services, Inc.; Eglin Air Force Base, Florida (International Foundation for Telemetering, 1991-11)
      The Gulf Range Drone Control Upgrade System (GRDCUS) Mobile Control System (GMCS) is an integral part of the test ranges located on the Gulf of Mexico. This paper begins with a brief overview of the current Gulf Range systems. These systems consist of five major components: ground stations, ground computer systems, data link/transponders, consoles, and software. The GMCS van contains many of these components to provide a stand-alone range capability for remote operations. This paper describes the development and assembly of the GMCS van and focuses on the on-board computer systems, consoles, and data link technology. An overall system engineering approach was used during GMCS development and is highlighted through the use of rapid prototyping. This methodology and the lessons learned are presented in the paper. Suggestions for future applications are considered.
    • HARDWARE PRE-PROCESSING FOR DATA OF UNDERWATER MEASURING SYSTEM

      Mukun, Wang; Gozhi, Liu; Zhenglian, Li (International Foundation for Telemetering, 1991-11)
      The synchro double pulse signal mode is freqently used in Short Base Line (SBL) underwater positioning system so as to obtain the information of both distance and depth of a target simultaneously. Howerer, this signal mode also brings about ranging indistinctness resulting in a shorter positioning distance much less than that limited by the period of the synchro signal. This paper presents a hardware distance gate date acquiring scheme. It puts the original data sent to the computer in order of “direct first pulse--depth information pulse (or first pulse reflected by water surface)•••- to guarantee the effective positioning distance of the system. It has the advantage of reducing the processing time of the computer thus ensuring the realtime functioning of the system.