• International Telemetering Conference Proceedings, Volume 27 (1991)

      International Foundation for Telemetering, 1991-11
    • 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.
    • 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.
    • MODERNIZING THE REMOTE TRACKING STATION

      Blanchard, W. N. (International Foundation for Telemetering, 1991-11)
      Since the inception of the Air Force Satellite Control Network (AFSCN) in the late 1950s, capabilities of the network’s Remote Tracking Stations (RTSs) were evolutionarily developed to meet satellite Tracking, Telemetry, and Commanding (TT&C) needs. The result, although fully satisfactory operationally, was an RTS network requiring manpowerintensive mission support. Additionally, reconfiguration of an RTS between satellite contacts consumed far more time than was operationally desirable as demands for RTS contact support continued to grow. To improve network responsiveness and cost effectiveness, the Air Force undertook, in the mid-1980s, a major “block upgrade” under the Automated Remote Tracking Station (ARTS) Program. This paper traces historical RTS capabilities, identifies emerging mid1980s RTS support requirements, and defines the operational and financial advantages accruing to the Air Force through ARTS implementation to meet those requirements. Possible future upgrades to further enhance AFSCN TT&C mission capability are also briefly discussed.
    • 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.
    • A Real-time Counting-measuring Method for PPM(PPK) Signals

      Xi-Hua, Li; Xinan Electronic Engineering Institute, China (International Foundation for Telemetering, 1991-11)
      On the disscussion of custom real-time counting-measuring method, this paper presents a new method suitable for the working condition of non-man duty, which possesses the feature of 100ns counting-measuring accuracy and high fidelity. In addition, the concept of “Signal-time/digit converter” is proposed for the first time and the principle and working procedure of this method are introduced in brief.
    • RAPID PROTOTYPING AS AN ACQUISITION STRATEGY OF THE AIR FORCE SATELLITE CONTROL NETWORK

      Whipple, L.K.; Hoida, T.J.; USAF Space Systems Division (International Foundation for Telemetering, 1991-11)
      The Air Force Satellite Control Network (AFSCN) processes on the order of a thousand separate requirements each year to enhance Network capability to meet the support needs of various satellites. Many of these individual requirements are translated into modifications or additions to the network assets. Rapid Prototyping has been utilized successfully for complex and urgent developments to meet many of these requirements. Rapid Prototyping has also been used for requirements definition and for defining man/machine interfaces. Through Rapid Prototyping, the AFSCN has successfully developed applications using new technology and has improved the process of defining requirements for operational satellite support systems. Rapid prototyping is proving to be an effective alternative to the traditional system acquisition process
    • 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.
    • 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.
    • 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.
    • THE BRIDGE FUNCTION TELEMETRY SYSTEM

      Qishan, Zhang; BEIJING UNIVERSITY OF AERONAUTICS AND ASTRONAUTICS (International Foundation for Telemetering, 1991-11)
      Based on the theory of orthogonality, two orthogonal multiplex systems called frequency division multiplexing (FDM) and time division multiplexing (TDM) have long been developed. Therefore, many people tend to think that these two systems represent the ONLY two multiplexing methods that satisfy the orthogonal condition. However, after years of research, we've discovered a new kind of orthogonal functions called Bridge functions. The Bridge functions have the every promise of being the basis for constructing an entirely new kind of telemetry system, which has been named as sequency division multiplexing (SDM). Since the Bridge functions are the mathematical basis of the new telemetry system, we will give a summary of the Bridge functions at first. We have successfully constructed an experimental prototype called BAM-FM system in our laboratory. The main ideas, block diagram, operational principles, and technical problems are discussed in this paper. All our work has proved that SDM has not only research interests, but also practical value.
    • THE ROLE OF THE PC IN GROUND TELEMETRY DATA ANALYSIS

      Burkhart, Fred; Chang, Chia-Mu; Loral Instrumentation (International Foundation for Telemetering, 1991-11)
      The growth of personal computer use was explosive in the last decade. In the telemetry industry, however, the adaptation and utilization of a PC-based telemetry instrument for high-speed data processing and display did not come about until the Intel 80386™ or equivalent processors were widely used in the late 1980s. At this time, the power of these processors finally began to meet the requirement to display, store, and play back the high-speed data (such as 10 Mbps with an embedded asynchronous data stream) that is typical in telemetry applications. Many users are still hesitant to use PCS for their telemetry applications because of the real-time limitations of these instruments. This paper will examine the advantages and disadvantages of PC-based test equipment, the performance these instruments, and the future of PC-based telemetry instrumentation. This paper will also focus on Loral Instrumentation’s d*STAR as an example of a PC-based telemetry system.
    • 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.
    • Implementation of a Reliable Satellite Commanding and Telemetry System

      McKean, Dan; USAF Space Systems Division (International Foundation for Telemetering, 1991-11)
      A spacecraft command and control system has unique requirements in the areas of telemetry and other data processing. Not only must the system support the processing of high data rate telemetry, but it must also simultaneously support outgoing command streams, usually coupled to the incoming telemetry. In addition, the system must reliably support several satellites (with up to twenty contacts each day per satellite) and be capable of week-long continuous contact with recently launched satellites. Integrating vehicle commanding with a telemetry system utilizing distributed software and hardware processing in such a fashion that no mission data is lost, and presenting the operator with a clean user interface, are just some of the technical challenges that were met in the design of the Operational Mission Unique Equipment (OMUE) project, which was installed earlier this year at the Consolidated Space Test Center (CSTC) at Onizuka AFB, California. This paper describes several of the technical trade-offs that were made in developing the OMUE system and its implementation.
    • A PRECISION TRANSPORTABLE TRACKING TELEMETRY SYSTEM

      Morris, R.A.; Powell, W.R.; Bundick, S.N.; Scientific-Atlanta, Inc.; NASA/Goddard Space Flight Center (International Foundation for Telemetering, 1991-11)
      Changing mission requirements have forced NASA to procure a new generation of tracking telemetry system with performance and features greatly exceeding existing system capabilities in many areas. These requirements and the system that was designed to meet them are discussed. Initial results of system testing are presented.
    • 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.
    • 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.
    • MODERN TECHNIQUES FOR MONITORING AIRBORNE TELEMETRY

      Berger, Haim; Schechter, Jacob; IAI - Israel/MLM (International Foundation for Telemetering, 1991-11)
      The testing and integration of modern avionic systems is facing us with new dimensions of complexity and sophistication. A smaller, faster avionic distributed processing system and small airborne spaces are demanding a new, innovative way to handle the telemetry requirements. The various types of data, ranging from analog values like temperature, vibrations, pressure and bi-level signals, up to the contents of fast buses like the MIL-STD-1553B and/or distributed multi-processor systems (performing calculations of a distributed nature) challenge the telemetry engineer coping with this task in the most efficient way.
    • IMAGE DATA COMPRESSION (USING DPCM)

      Karki, Maya; Shivashankar, H.N.; Rajangam, R.K.; Dept. of Electrical Engg., U.V.C.E., Bangalore; DSD-ISRO, Bangalore (International Foundation for Telemetering, 1991-11)
      Advances in computer technology and mass storage have paved the way for implementing advanced data compression techniques to improve the efficiency of transmission and storage of images. The present paper deals on the development of a data compression algorithm suitable for images received from satellites. The compression ratio of 1.91:1 is achieved with the proposed technique. The technique used is 1-D DPCM Coding. Hardware-relevant to coder has also been proposed.