• 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.
    • 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.
    • EFFECT OF PCM ENCODING ON WIDE BAND TELEMETRY DATA

      Cox, T. F.; Nichols, M. H.; Naval Weapons Center (International Foundation for Telemetering, 1984-10)
      In order to comply with certain mission requirements, it is necessary to encode telemetry data into pulse code modulation (PCM). For this reason, test data have been obtained in order to determine the effects of quantization errors and bit errors with special reference to wide band noise-like data signals involving data reduction by spectral analysis. The use of notch noises tests for determining coder/decoder (CODEC) performance has been evaluated. Test procedures and test results are given using CODEC configurations of 4 to 12 bits per word. Parameters for encoding constant bandwidth (CBW) and proportional bandwidth (PBW) subcarrier multiplexes for PCM transmission are 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.
    • 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.
    • 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.
    • HIGH DATA RATE RADAR AND TELEMETRY SIGNAL COLLECTION

      Cumming, Colin J.; Frontier Engineering, Inc. (International Foundation for Telemetering, 1984-10)
      Collection of radar and telemetry data has always been limited by bandwidth and storage capacity factors. This paper examines some of the constraining factors in achieving very high data rates and storage capacities. A number of new technologies are examined for applicability. A special purpose modular architecture oriented towards high speed bulk data acquisition is presented. Several systems are described including systems based on Winchester disks, high speed parallel transfer disks, bulk RAMs, HDDR, and others. Special emphasis is placed on the unique data acquisition requirements of radar and telemetry signal collection.
    • SINGLE EVENT UPSETS IN SPACECRAFT DIGITAL SYSTEMS

      Lewkowicz, Paul E.; Richter, Linda Jean; Hughes Aircraft Company (International Foundation for Telemetering, 1984-10)
      This paper describes the physical environment that can result in random bit changes in space-borne memory systems. The impact of bit flips in digital telemetry systems is emphasized, with special attention paid to software requirements for protection from single event upset (SEU) effects. Some observations on incidence rates are presented along with an outline of hardware and software methods that can be taken to prevent future SEU problems. Several conclusions are drawn about strategies for preventing data corruption on the next generation of satellites in the presence of SEU-inducing particles.
    • 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.
    • TRACKING AND DATA RELAY SATELLITE SYSTEM (TDRSS) SYSTEM OVERVIEW AND REIMBURSABLE USE

      Scott, James N.; Goddard Space Flight Center, National Aeronautics and Space Administration (International Foundation for Telemetering, 1984-10)
      The first satellite (TDRS-1) of the three-satellite TDRSS was launched by NASA in April 1983. A booster failure resulted in a delay in achieving the final synchronous orbiting position (until the following October) and has caused a delay in the launching of the second and third satellites. Nevertheless, NASA has obtained considerable operational experience with TDRS-1 and is generally pleased with the performance to date. This paper will provide an overview of how the TDRSS operates and its status, and will provide information about the policy, costs, and procedures regarding use of the system by non- NASA organizations.
    • A UNIQUE 155 MM BALLISTIC SHOCK AIR GUN

      Stewart, E. Kenneth; US Army Armament Research and Development Center (International Foundation for Telemetering, 1984-10)
      A rifled soft recovery air gun used as a ballistic simulator is described and compared to conventional smooth bore air guns. These gun systems provide shock tests for qualification, quality control, and research and development of many items, including telemetry systems and components. The laboratory environment in which they operate is responsible for lower test costs than field tests, and for a higher average number of retests of expensive telemetry units.
    • The Role of Telemetry In Navstar Checkout

      Radak, J. Jr.; Mercadante, D. S. (International Foundation for Telemetering, 1984-10)
      Numerous checkout systems are being conceived for factory test, launch readiness assessment, and on-orbit performance evaluation for spacecraft designs of ever-increasing complexity. These systems must in addition be extremely flexible in design to maintain supportive capability at reasonable cost during transition from development through operational program phases. This paper describes a telemetry dependent checkout system for the Navstar Global Positioning Satellite. The Space-Ground Link System (SGLS) compatible telemetry based checkout features elemental units that simulate the Satellite Test Center (STC) and the Remote Tracking Stations (RTS). This approach minimizes the duplication of hardware and software design and documentation for the overall spacecraft assembly-to-orbit checkout process. The telemetry-checkout design is shown to be versatile enough to support growth in both numbers and types of payloads; to reduce the operator training demands; to provide test results, equipment status, and other data to remote evaluation personnel; and to improve delivery through computer-assisted performance assessments.
    • 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.
    • 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.
    • 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)
    • SOFT RECOVERY SYSTEMS FOR GUN-FIRED PROJECTILE COMPONENTS

      Fritch, Paul L.; Spinelli, Carmine J.; Armaments Research and Development Center (International Foundation for Telemetering, 1984-10)
      Artillery projectile designers have found an ever increasing need to soft recover prototype hardware and componentry in actual gun firings. Further, as projectile fuzes and guidance systems become more sophisticated, and with the increased use of telemetry and on-board memory systems, the soft recovery technique has become a necessity for the projectile development community. Described herein are parachute soft recovery techniques currently being used by the U.S. Army Armament Research and Development Center (ARDC), Large Caliber Weapon Systems Laboratory, Dover, NJ. In one parachute recovery system, the complete projectile body section is recovered. In another system, the nose-fuze/TM section is recovered. And in a third system, a jettisoned canister, housing electro-mechanical components, is recovered.
    • 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.
    • 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.