Caldera, M. C.; Paz, Marco; Edwards Air Force Base; Naval Air Warfare Center Aircraft Division (International Foundation for Telemetering, 1993-10)
      The Advanced Airborne Test Instrumentation System (AATIS) was developed by the Air Force to satisfy its flight-test mission needs through the 1990s. The Common Airborne Instrumentation System (CAIS) is a tri-service development aimed at providing a common airborne data acquisition system for all DoD flight-test programs into the next century. Both AATIS and CAIS include ground support equipment which performs the primary functions of documenting the instrumentation system, generating and loading the telemetry data formats, and performing instrumentation system diagnostics. The AATIS and CAIS ground systems will each support both the AATIS and the CAIS airborne systems. The AATIS ground system also supports the older ATIS airborne systems. The approach taken by the two ground support systems is similar but the scope of functionality is larger in the AATIS ground system because it needed to respond to the more extensive ground support requirements of the Air Force users. This paper provides a brief description of both ground systems and discusses the issues of commonality and interoperability.

      Gaddis, William R. Jr; Sandland, Sawn; Edwards Air Force Base (International Foundation for Telemetering, 1993-10)
      DOD flight test centers need affordable, small-format, flight-qualified digital instrumentation recording solutions to support existing and future flight testing. The Advanced Airborne Test Instrumentation System (AATIS) is today's primary data acquisition system at the Air Force Flight Test Center (AFFTC). Digital Recorder (DR) 1995 is planned to provide full support for AATIS output capabilities and satisfy initial recording requirements for the Common Airborne Instrumentation System (CAIS). The follow-on to the AATIS, the CAIS is a tri-service development to satisfy future DOD flight test data acquisition requirements. DR 2000 is planned as the future recording solution for CAIS and will be able to fully satisfy the 50 Mbps recording requirement. In the developments of DR 1995 and DR 2000, commonality and interoperability have emerged as significant issues. This paper presents an overview of these recording solutions and examines commonality and interoperability issues.

      Chang, Dah W.; Edwards Air Force Base (International Foundation for Telemetering, 1993-10)
      The Advanced Airborne Test Instrumentation System (AATIS), one of the major instrumentation systems in use today by the Department of Defense (DoD), was developed in the late 1980's to improve and modernize its predecessor - the Airborne Test Instrumentation System (ATIS). Use of AATIS, by not only the Air Force but the Navy and Army, has improved instrumentation commonality and interoperability across multiple test programs. AATIS, developed by the same manufacturer as the DoD Common Airborne Instrumentation System (CAIS), has a common bus structure - enabling cross utilization of many components which will ease transition from one system to another. The objective of this paper is to provide an overview on the Advanced ATIS System and its logistics support concept. For system description, an overview is presented on the airborne system and related ground support equipment. A brief description is given on the three levels of maintenance being used or planned for by the using activities. Finally, a projection is presented on the utilization of this system for the next 3 years.
    • Aircraft Tracking of Underwater Vehicles Equipped with Optical Beacons

      Casey, Thomas; Estes, Lee; Fain, Gilbert; Naval Undersea Warefare Center Division (International Foundation for Telemetering, 1993-10)
      During shallow water exercises, the performance of acoustic tracking and telemetry systems is degraded by severe multipath interference. The feasibility of an optical source attached to the underwater vehicle (UV) and a tracking aircraft-based receiver was theoretically established. Supporting water absorption and surface interaction experiments were also performed. The limiting case was the tracking of an unmanned underwater vehicle (UUV). The requirements of daylight operation, atmospheric visibility, limited space and weight, self-contained power, exercise duration, sample rate, optimum search area, robustness in varying scattering and sea states, non-cooperating (except for low-data-rate communications of information such as depth) source and receiver, and relative simplicity, lead to two optimum candidate systems. One system uses a commercially available 5 megawatt q switched and double laser diode pumped YAG laser operating at 532 nm and 1 Hz rep rates. The second system uses a pulsed (2 μsec) zenon flash tube. Both systems satisfy the robustness constraint by intentional beam spreading. A performance constraint of 10:1 signal to noon solar upwelling shot noise ratio was imposed. This constraint can be met for water depths of 10 and 5 absorption lengths, respectively, for the laser and incoherent systems. An optimum search diameter of approximately 700 meters (m) at an optimum aircraft elevation of 3,000 meters is calculated for both systems. The 4-inch diameter F/1 wide-angle light pulse detection system gates a 4-inch diameter F/1 intensified charged coupled device (CCD) imaging system that locates the light surface penetration point. Another candidate receiver that performs both functions is a positive sensitive photomultiplier tube with crossed wire anodes. A supporting night-time experiment has been designed and is under construction.

      Josie, Michael W.; Brigham Young University (International Foundation for Telemetering, 1993-10)
      This paper describes an alterative soft-decision decoding algorithm to be used in hybrid-ARQ error control communication systems. This new scheme promises significant reductions in decoder complexity while exhibiting performance levels comparable to contemporary soft-decision decoders. The development of this algorithm is discussed briefly, its implementation is explained, and the results of computer analysis already performed are considered. It will be shown that the method presented is conducive to the use of a significantly reduced codeword searching algorithm, yielding the advantages of correlation decoding without the corresponding complexity. Keywords: soft-decision block decoding, hybrid- ARQ (Automatic-Repeat-Request) error control, correlation decoding, additive white Gaussian noise channel.
    • Analysis of Frequency Stabilization and Modulation of Airborne Telemetry Transmitter

      Xizhou, Zhang; Jun, Yao; Xinan Electronic Engineering Institute (International Foundation for Telemetering, 1993-10)
      This paper analyzes the feature of frequency stability and modulation of airborne telemetry transmitters. According to the characteristic of telemetry information transmission, several methods for frequency stabilization and modulation are briefly compared. Emphasis is given to discuss frequency dividing phase- locked frequency modulation and on-off keying modulation and FM/on- off keying double modulation. With the view of raising frequency stability and modulation sensibility, extending the linear range of modulation, the contradiction between frequency stabilization and modulation should be coordinated properly. In addition, a compatible method between conventional telemetry channel and super fast signal telemetry channel is introduced. A satisfactory result has been acquired with those views and methods used in engineering application.

      Kight, William D.; Pfister, Robert E.; PKE, Inc. (International Foundation for Telemetering, 1993-10)
      This paper addresses the creation of a large virtual-range environment whereby multiple, geographically dispersed, test ranges may operate in concert to support test operations. The most significant benefit of the virtual range environment is the time-sharing of costly processing resources. Other benefits include improved reliability and responsiveness of inter-range data transfer. This paper will focus on existing and near-term technology that may be applied to create a virtual-range and will address the technological and economic advantages and disadvantages of TDM vs. ATM approaches.

      Forman, Michael L.; Hazra, Tushar K.; Troendly, Gregory M.; Nickum, William G. (International Foundation for Telemetering, 1993-10)
      The performance and cost effectiveness of em bedded processing has greatly enhanced the personal computer's (PC) capability, particularly when used for real-time satellite data acquisition, telemetry processing, command and control operations. Utilizing a transputer based parallel architecture, a modular, reusable, and scalable control system is attainable. The synergism between the personal computer and embedded processing results in efficient, low cost desktop workstations up to 1000 MIPS of performance.
    • An Approach for Standardization of Datalink Systems

      Bolino, John V.; Lenz, Russell W. (International Foundation for Telemetering, 1993-10)
      The paper explores the concept of standardization of datalink systems and makes a call for industry involvement in the process of defining an approach to standardization. The objectives are to reduce the Department of Defense (DoD) cost of Major Range and Test Facility Base (MRTFB) operations, to improve interoperability, to have the flexibility to meet unique user needs, to have compatibility with existing systems and standards, and to have the ability to evolve to a next generation of datalink systems. The paper describes several current DoD Central Test and Evaluation Investment Program (CTEIP) projects and shows how dependent and interdependent they are on datalink systems. A new Joint Service CTEIP project, Standard Interoperable Datalink System (SIDS), will become the facilitator in the process of defining a standard datalink, including weapon system/platform telemetry, time-space-position information, target command and control, voice communications, time correlation data, and possibly video.
    • Automated Analysis Tools for Reducing Spacecraft Telemetry Data

      Voss, T. J.; Lawrence Livermore National Laboratory (LLNL) (International Foundation for Telemetering, 1993-10)
      A practical description is presented of the methods used to reduce spacecraft telemetry data using a hierarchial toolkit of software programs developed for a UNIX environment.
    • Automated Application of Calibration Factors on Telemetered Data

      Kalibjian, J. R.; Voss, T. J.; Yio, J. J.; Lawrence Livermore National Laboratory (International Foundation for Telemetering, 1993-10)
      A long standing problem in telemetry post processing is the application of correct calibration factors to telemetered data generated on a system which has had a history of hardware changes. These calibration problems become most exacerbated when old test data is being examined and there is uncertainty as to hardware configuration at the time of the test. In this paper a mechanism for introducing a high degree of reliability in the application of calibration factors is described in an implementation done for Brilliant Pebbles Flight Experiment Three (FE-3).
    • Automated Binding of Attributes to Telemetry Data

      Kalibjian, J. R.; Voss, T. J.; Yio, J. J.; Hedeline, B.; Lawrence Livermore National Laboratory; Ball Aerospace Systems Group (International Foundation for Telemetering, 1993-10)
      An automated method is described for binding attributes to extracted data from a telemetry stream. These attributes can be used by post processing utilities to facilitate efficient analysis. A practical implementation of such a scheme is described.
    • Batch Processing of Flight Test Data

      Turver, Kim D.; Boeing Commercial Airplane Group (International Foundation for Telemetering, 1993-10)
      Boeing's Test Data Retrieval System not only acts as an interface between the Airborne Data Acquisition System and a mainframe computer but also does batch mode processing of data at faster than real time. Analysis engineers request time intervals and measurements of interest. Time intervals and measurements requested are acquired from the flight tape, converted to first order engineering units, and output to 3480 data cartridge tape for post processing. This allows all test data to be stored and only the data of interest to be processed at any given time.
    • Bit Error Problems with DES

      Loebner, Christopher E. (International Foundation for Telemetering, 1993-10)
      The Data Encryption Standard (DES) was developed in 1977 by IBM for the National Bureau of Standards (NBS) as a standard way to encrypt unclassified data for security protection. When the DES decrypts the encrypted data blocks, it assumes that there are no bit errors in the data blocks. It is the object of this project to determine the Hamming distance between the original data block and the data block after decryption if there occurs a single bit error anywhere in the encrypted bit block of 64 bits. This project shows that if a single bit error occurs anywhere in the 64-bit encrypted data block, a mean Hamming distance of 32 with a standard deviation of 4 is produced between the original bit block an the decrypted bit block. Furthermore, it is highly recommended by this project to use a forward error correction scheme like BCH (127, 64) or Reed-Solomon (127, 64) so that the probability of this bit error occurring is decreased.

      Hoaglund, Catharine M.; Gardner, Lee S.; Bender, Victor W.; Edwards Air Force Base (International Foundation for Telemetering, 1993-10)
      The increasing complexity and volume of the information needed to support flight test missions has led to a need to expand the capability of current test data management systems. While the abilities currently exist to collect and manage calibration and telemetry information in an automated fashion, new requirements have emerged to link this data with other systems and to expand the functions and devices supported. Coordinating and directing the overall flow of information required for a successful flight test is a very big task. It calls for a view into flight test planning and scheduling activities, test objectives and methods, and the requirements for viewing and processing the test data in real-time and postflight. To meet this challenge, the Automated Test Data Management System (ATDMS) is being developed at the Air Force Flight Test Center (AFFTC), Edwards AFB, California. This paper describes the critical information and interfaces that the ATDMS will manage to bring cohesion to the management of flight test support data.
    • The Common Airborne Instrumentation System Program Overview

      Jones, Sidney R. Jr; Naval Air Warfare Center, Aircraft Division (International Foundation for Telemetering, 1993-10)
      The Common Airborne Instrumentation System (CAIS) is being developed by the Department of Defense through a Tri-service Program Office. The goals of the program are two fold. The first is to develop an instrumentation system that will meet the needs of the Air Force, Army, and Navy into the next century. The system is designed to support a full breadth of applications from a few parameters to engineering and management and development programs. The second is to provide a system that is airframe as well as activity independent. To accomplish these goals, the CAIS consists of two segments. The airborne segment consists of a system controller with a suite of data acquisition units. The system is configured with only the units that are required. The ground segment consists of a variety of support equipment. The support equipment enables the user to generate formats, load/verify airborne units, perform system level diagnostics and more.
    • A Comparison of Various Video Compression Methods for Use in Instrumentation Systems

      Rieger, James L.; Gattis, Sherri L.; Naval Air Warfare Center, Weapons Division (International Foundation for Telemetering, 1993-10)
      Various forms of 'lossy' and 'lossless' encoding have been implemented or proposed to allow compression of still and motion picture images, with varying degrees of success which in turn depend on how success is defined. Proponents of various systems claim 'compression ratios' which by their nature defy comparison of one system with another and suggest there actually may be something like a free lunch. This paper compares various compression methods as well as the implications involved in using them and what happens when different systems encounter the problems associated with the uses of the restored picture.

      Cardinal, Robert W.; Loral Instrumentation (International Foundation for Telemetering, 1993-10)
      This paper describes the recently developed Loral Instrumentation ground-based equipment used to select and process post-flight test data from the Boeing 777 airplane as it is played back from a digital tape recorder (e.g., the Ampex DCRSi II) at very high speeds. Gigabytes (GB) of data, stored on recorder cassettes in the Boeing 777 during flight testing, are played back on the ground at a 15-30 MB/sec rate into ten multiplexed Loral Instrumentation System 500 Model 550s for high-speed decoding, processing, time correlation, and subsequent storage or distribution. The ten Loral 550s are multiplexed for independent data path processing from ten separate tape sources simultaneously. This system features a parallel multiplexed configuration that allows Boeing to perform critical 777 flight test processing at unprecedented speeds. Boeing calls this system the Parallel Multiplexed Processing Data (PMPD) System. The key advantage of the ground station's design is that Boeing engineers can add their own application-specific control and setup software. The Loral 550 VMEbus allows Boeing to add VME modules when needed, ensuring system growth with the addition of other LI-developed products, Boeing-developed products or purchased VME modules. With hundreds of third-party VME modules available, system expansion is unlimited. The final system has the capability to input data at 15 MB/sec. The present aggregate throughput capability of all ten 24-bit Decoders is 150 MB/sec from ten separate tape sources. A 24-bit Decoder was designed to support the 30 MB/sec DCRSi III so that the system can eventually support a total aggregate throughput of 300 MB/sec. Clearly, such high data selection, rejection, and processing will significantly accelerate flight certification and production testing of today's state-of-the-art aircraft. This system was supplied with low level software interfaces such that the customer would develop their own applications specific code and displays. The Loral 550 lends itself to this kind of applications due to its VME chassis, VxWorks operating system and the modularity of the software.

      Ritter, Thomas M.; Pratt & Whitney CEB (International Foundation for Telemetering, 1993-10)
      Pulse Code Modulation (PCM) data systems are used extensively in testing aircraft all over the world. These systems can be tailored to almost any set of measurement requirements using flexible, modular equipment available from several sources. This paper describes a system assembled from readily available components manufactured in the United States that is being used to certify a Russian aircraft flying in The Commonwealth of Independent States. The system features distributed data acquisition, programmable signal conditioning and PCM encoding modules, multi-channel temperature and pressure scanners and real time data displays on board the aircraft. The impact of U.S. export controls and our experience to date is also discussed.

      Oosthoek, Peter B.; National Aerospace Laboratory NLR (International Foundation for Telemetering, 1993-10)
      Information management is of essential importance during design and operation of flight test measurement systems to be used for aircraft airworthiness certification. The reliability of the data generated by the realtime- and post-processing processes is heavily dependent on the reliability of all provided information about the used flight test measurement system. Databases are well fitted to the task of information management. They need however additional application software to store, manage and retrieve the measurement system configuration data in a specified way to support all persons and aircraft- and ground based systems that are involved in the design and operation of flight test measurement systems. At the Dutch National Aerospace Laboratory (NLR) a "Measurementsystem Configuration DataBase" (MCDB) is being developed under contract with the Netherlands Agency for Aerospace Programs (NIVR) and in cooperation with Fokker to provide the required information management. This paper addresses the functional and operational requirements to the MCDB, its data-contents and computer configuration and a description of its intended way of operation.