Richard, Gaetan C.; Gonzalez, Daniel G.; DECS, Inc; Malibu Research, Inc (International Foundation for Telemetering, 1994-10)
      The design of a telemetry tracking system is generally centered around its desired RF performance which is typically specified in terms of beamwidth, gain and/or G/T. These parameters determine the size of the reflector used in a given application and consequently dictate the required size and performance of the associated pedestal. Any subsequent improvement in the RF performance of such a system is primarily achieved by increasing the size of its reflector. The magnitude of the improvement realized is therefore limited by the load handling capability of the pedestal. In most instances, the substitution of a larger reflector with its increased inertia and wind loading causes a significant degradation in the dynamic performance of the tracking system. This paper describes how the figure of merit (G/T) of a specific dual axis telemetry tracking system can be improved by a minimum of 7.3 dB/K° without impacting its dynamic performance or increasing its weight. These impressive results are made feasible by the innovative pairing of a unique design planar reflector with a novel implementation of the conical scanner technology. The FLAPS™ reflector incorporates a newly developed concept which features lightweight construction and very low wind load coefficients [1, 2]. The conical scanner is a lightweight version of the DECS tracking feed system described in the referenced technical paper [3].
    • Chinese New Telemetry Onboard System

      Jie, Shi Chang; China Aerospace Corporation (International Foundation for Telemetering, 1994-10)
      This paper at first gives a brief historical review of Chinese development of telemetering onboard system and then make a brief introduction of new onboard system from several respects.

      Gaskill, David M.; ASTRO-MED INC. (International Foundation for Telemetering, 1994-10)
      This paper will examine real-time ethernet capabilities in general and will describe in detail a practical implementation of an Ethernet interface that allows commands and data to be sent to a thermal array recorder using a standard TCP/IP, Novell, or similar interface. This interface allows two types of data transmission. First, real-time data may be sent at low rates for slow speed monitoring or, second, high speed packets may be sent for storage in local FIFO memory. A header containing sample rate information allows the recorder to reconstruct the data on paper smoothly so that it has the appearance of real-time recording but is slightly delayed. In addition, normal host control commands may be interleaved with data for a complete high speed digital data system.

      Reinsmith, Lee V.; TYBRIN Corporation (International Foundation for Telemetering, 1994-10)
      This paper describes the application software used in the Message Processing System at the Air Force Development Test Center (AFDTC), Eglin AFB. The focus is on the Alpha AXP application software designed and developed to log, process, and reformat IRIG Chapter 8 1553 data. The main data reduction and editing capabilities of the processing phase are explained: message output selection, message output sampling, message translation, error identification, and IRIG Chapter 8 time editing. The design of and methods used to produce the output files, the BBNProbe STD file, and the 1553 message summary report are described. This software’s flexibility and comprehensiveness in processing, reducing, and re-formatting 1553 message data will enable AFDTC to satisfy current and future post-mission processing requirements.

      O'Brien, R. Michael; Loral Test & Information Systems (International Foundation for Telemetering, 1994-10)
      With today's telemetry systems, an hour-long analog test tape can be digitized in one hour or less. However, the digitized data produced by today's telemetry systems is usually not in a format that can be directly analyzed by the test engineer's analysis tools. The digitized data must be formatted before analysis can begin. The data formatting process can take from one to eight hours depending on the amount of data, the power of the system's host computer, and the complexity of the analysis software's data format. If more than one analysis package is used by the test engineer, the data has to be formatted separately for each package. Using today's high-speed RISC processors and large memory technology, a real-time Flexible Data Formatter can be added to the Telemetry Front End to perform this formatting function. The Flexible Data Formatter (FDF) allows the telemetry user to program the front-end hardware to output the telemetry test data in a format compatible with the user's analysis software. The FDF can also output multiple data files, each in a different format for supporting multiple analysis packages. This eliminates the file formatting step, thus reducing the time to process the data from each test by a factor of two to nine.
    • CCSDS Data Link Service Allocation for MIL-STD-1553B Bus Architecture on Small Payloads

      Minnix, Timothy Otto; Lujan, Manuel, Jr.; New Mexico State University (International Foundation for Telemetering, 1994-10)
      There has been much interest recently in the possibility of using the NASA Tracking and Data Relay Satellite System (TDRSS) instead of proprietary ground stations in supporting small space payload communications. These payloads operate on fairly low power and do not use the sophisticated tracking equipment standard on more complex user spacecraft. This paper is part of a feasibility study for such use of TDRSS, and focuses on the effect of the method of providing the Grade-2 data link layer services specified in Consultative Committee for Space Data Systems (CCSDS) Advanced Orbiting Systems (AOS) recommendations upon a hypothetical spacecraft using a MIL-STD-1553B polled data bus as the backbone of its onboard LAN. In particular, one case in which the 1553B bus controller, assumed to be some Intel 80X86 microprocessor, provides all CCSDS services will be contrasted with another where these services are split between the bus controller and a device which interfaces between the spacecraft LAN and the TDRSS Return Service spacelink. The comparison will be made for a 15 orbit/day scenario using a small helical antenna with a comparatively wide beamwidth. The main performance criteria considered here are end-to-end data throughput and expected delays, along with required buffer sizes for the LAN. Also, it may be noted that the data rate of the TDRSS return link and the size of the sliding window used for flow and error control will have a large impact on the required values for the chosen criteria, and so choices for these parameters significantly affect the outcome of any system service comparison. The two LAN types will be modeled and analyzed using NETWORK II.5. This simulator allows tracking of the number of packets read into LAN memories and sent down from the payload to ground via TDRSS, as well as accurately modeling the delays involved with data processing and transmission over the link.
    • XL-L: A Novel Two Axis Pedestal System Which Eliminates Keyholes and Has Complete Continuous Hemispherical Coverage Without the Use of Rotary Joints or Sliprings

      Augustin, Eugene P.; Sullivan, Arthur (International Foundation for Telemetering, 1994-10)
      The XL-L Two-axis Pedestal is a novel adaptation of an existing design using a cross elevation over elevation axis configuration. This design affords full hemispherical coverage without gimbal lock (keyholes). In addition, the system provides continuous coverage without the necessity of rotary joints and sliprings. The design is ideally suited for shipboard systems, but is equally advantageous for any tracking mission where the target can approach a zenith gimbal lock or keyhole.
    • A Software Architecture for Client-Server Telemetry Data Analysis

      Brockett, Douglas M.; Aramaki, Nancy J.; BBN Systems & Technologies (International Foundation for Telemetering, 1994-10)
      An increasing need among telemetry data analysts for new mechanisms for efficient access to high-speed data in distributed environments has led BBN to develop a new architecture for data analysis. The data sets of concern can be from either real-time or post-test sources. This architecture consists of an expandable suite of tools based upon a data distribution software "backbone" which allows the interchange of high volume data streams among server processes and client workstations. One benefit of this architecture is that it allows one to assemble software systems from a set of off-the-shelf, interoperable software modules. This modularity and interoperability allows these systems to be configurable and customizable, while requiring little applications programming by the system integrator.
    • Low Cost Vector Scoring System for Airborne Targets

      Whiteman, Don; Bradley, Joe; Naval Air Warfare Center, Weapons Division (International Foundation for Telemetering, 1994-10)
      Testing of airborne weapons systems often requires that a scoring system be placed on the target drone to obtain critical miss distance data. Advanced weapons utilizing directional warheads often require a scoring system which yields vector, miss distance and miss direction, information. Scalar scoring systems currently in use are relatively simple and inexpensive. Vector scoring systems are typically complex and the cost of systems which are currently available or are being developed can be prohibitively expensive. Due to the current military budget decline, development of a low cost vector scoring system is desirable This paper introduces a low cost vector scoring system developed for airborne target drones and based on an inexpensive scalar scoring system currently in use. To meet the low cost criteria, vector operation is achieved via minimal modifications to the existing scalar system.
    • Network Configuration for Range Interconnectivity

      Douglas, Steven R.; Naval Warfare Assessment Division (International Foundation for Telemetering, 1994-10)
      A demonstration of near real-time performance assessment for the Program Executive Officer for Cruise Missiles Project and Unmanned Aerial Vehicles, Cruise Test Directorate, PEO(CU)-CT, was conducted between 22 March 1994 through 4 May 1994. The demonstration involved the temporary installation of a portable TOMAHAWK telemetry recording and telecommunications capability at the Air Force Development Test Center range at Eglin Air Force Base, Florida and a receiving telecommunications capability at the Naval Warfare Assessment Division (NWAD), Corona, California. The system was successfully used on 4 May 1994 to record TOMAHAWK missile telemetry data in real-time in support of Operational Test Launch (OTL)-163 and to transfer that data to the weapons system performance analysts at NWAD in near real-time. The one hour and three minutes of flight data was compressed in real-time as it was recorded, then, after completion of the flight, the data was transferred to NWAD in about 12 minutes using the switched 56 kbps network. Additional transfers using the Defense Commercial Telecommunications Network (DCTN) were also conducted. All transfers were secured using ethernet encryptors. The data was processed by both the NWAD telemetry ground station and the TOMAHAWK workstation complex. This paper quantifies the results and documents the lessons learned from this demonstration and proposes a standardized system design for possible implementation at TOMAHAWK test range sites in the future. A position is taken that for situations where the remote site (e.g. other range or data analysis site) does not exercise direct operational control over the test/host range, near real-time data relay solutions are not only as adequate, but in many cases are preferable to real-time solutions.
    • Wideband FM Telemetry Application

      Neuens, Jim; Veda Incorporated (International Foundation for Telemetering, 1994-10)
      A Wideband FM Telemetry System was developed by Veda Incorporated and Boeing Commercial Airplane. This system supports Boeing 777 flight testing and will support future Boeing test efforts. This is an upgrade to the system previously used by Boeing for testing other planes. The design interfaces to the new Boeing Data Acquisition and Analysis systems and provides 15 Megabits per second Telemetry at ranges up to 180 miles. This paper provides details regarding the following design and integration issues: o) RF Transmitter Design o) RF Receivers o) Airborne Antenna o) Ground Based Antenna o) Data Interfaces o) System Performance o) Problems / Solutions
    • Space Tracking Systems/ Options Study

      Grelck, John; Ehrsam, Eldon; Means, James A. (International Foundation for Telemetering, 1994-10)
      This paper presents the findings of the Space Tracking Systems/Options Study (STS/OS) and indicates its impact on the telemetering community. The STS/OS was commissioned by Air Force Test & Evaluation (AF/TE) to develop a long range plan (vision and roadmap) for the AF Test & Evaluation (T&E) community to ensure affordable capabilities (telemetry, tracking and commanding) for the future (2003-2008). The study was conducted by the Air Force Materiel Command (AFMC), Space & Missile Systems Center (SMC), Detachment 9, at Vandenberg AFB (VAFB), with support from the primary AFMC T&E centers, the Air Force Operational Test & Evaluation Command (AFOTEC), and the Air Force Space Command (AFSPC). Both "open air" aeronautical and astronautical test needs were considered. The study solicited requirements for existing and future programs, extrapolated existing and planned test capabilities out into the future, then compared the two to identify future shortfalls in capabilities and specific actions that are necessary to insure that the future program needs can be met. Three critical types of testing were identified that cannot be satisfied with existing or planned instrumentation. These are: large area testing (LAT), over the horizon testing (OTH), and space weapons testing (SWT). A major deficiency was also uncovered in end game scoring for air and space intercepts, where inadequate capability exists to perform the required vector miss-distance measurement. This paper is important to the telemetering community because it identifies the Global Positioning System (GPS) as the primary time space position information (TSPI) system for all future open air testing. GPS provides a passive capability that permits each vehicle to determine its own precise TSPI. Means must be provided, however, for the vehicle to relay its position to the appropriate range control center. The paper shows that the problems with down linking telemetry, aircraft buss data, digital audio, digital video, and TSPI collectively represent the need for a very capable datalink. Likewise, the need to uplink commands, synthetic targets, synthetic backgrounds, and target control information also represents the need for a very capable datalink. With its extensive expertise in RF linkages, the telemetering community is ideally suited to address this need for a robust datalink for the future of T&E.

      Rucinski, Gary; BBN Systems and Technologies (International Foundation for Telemetering, 1994-10)
      In recent years the extension of interactive simulation technology to involve simulators and live vehicles from geographically dispersed sites has produced a demand for high-bandwidth communication networks that can provide guaranteed quality of service (e.g., insured availability of bandwidth and upper bounds on end-to-end delay). This paper reviews the requirements distributed interactive simulation places on the communications infrastructure and describes the Defense Simulation Internet (DSI), a network developed by the Advanced Research Projects Agency to support distributed interactive simulations. Key features of the DSI are: more than 120 participating sites spanning Europe, the United States and Asia; use of a resource reservation mechanism to provide guaranteed quality of service; and support for communication between classified sites. Furthermore, the paper describes the internetworking protocols used in the DSI to provide guaranteed quality of service and to support transmission of classified communications. Other topics discussed in the paper are research efforts that anticipate increased load on the DSI and the relevance of the technology to the integration of the telemetry range and distributed interactive simulations.
    • Improved Groundstation Consoles Using New Visualization Techniques and Graphics Technology

      McDaid, John P., Jr.; Loral Test & Information Systems (International Foundation for Telemetering, 1994-10)
      The advance from alphanumeric terminals to displays using new graphics technologies like the X Window System and Microsoft Windows has in many cases failed to tap the full potential of these technologies. Many common telemetry tasks continue to use similar user interfaces based on tabular real-time data displays and menus. This paper will demonstrate the application of new techniques which, when used with emerging graphics technologies, will maximize the effectiveness of telemetry ground station consoles. Advances in visualization and animation have greatly enhanced the information content of current displays and significantly improved their ease of use.
    • The Common Airborne Instrumentation System Program Management Overview

      Brown, Thomas R., Jr.; Naval Air Warfare Center, Aircraft Division (International Foundation for Telemetering, 1994-10)
      The Department of Defense, through a Tri-Service Program Office, is developing the Common Airborne Instrumentation System (CAIS) to promote standardization, commonality, and interoperability among aircraft test instrumentation systems. The advent of CAIS will change how the DoD test community conducts business. The CAIS program will allow aircraft test and evaluation facilities to utilize common airborne systems, ground support equipment, and technical knowledge for airborne instrumentation systems. The CAIS Program Office will conduct requirements analyses, manage system upgrades, and provide full life cycle support for this system. It is initiating several requirements contracts to provide direct ordering opportunities for DoD users to easily procure defined test instrumentation hardware. The program office will provide configuration management, inventory control, maintenance support, system integration, engineering support, and software management. In addition, it will continue to enhance the current system and develop new items to meet future requirements. Where existing equipment provides added benefit, this equipment may be added to the official CAIS family.

      Schwartz, Paul D.; Hersman, Christopher B.; The Johns Hopkins University (International Foundation for Telemetering, 1994-10)
      A system to generate a contiguous high speed time division multiplexed (TDM) spacecraft downlink data stream has been developed. The 25 MBPS downlink data stream contains high rate real time imager data, intermediate rate subsystem processor data, and low rate spacecraft housekeeping data. Imager data is transferred directly into the appropriate TDM downlink data window using control signals and clocks generated in the central data formatter and distributed to the data sources. Cable and electronics delays inherent in this process can amount to several clock periods, while the uncertainty and variations in those delays (e.g. temperature effects) can exceed the clock period. Unique (patent pending) electronic circuitry has been included in the data formatter to sense the total data gathering delay for each high speed data source and use the results to control series programmable delay elements to equalize the delays from all sources and permit the formation of a contiguous output data stream.

      Policella, Joseph; Kleen, Mitchell; White, Joey; CAE-Link Corporation (International Foundation for Telemetering, 1994-10)
      In space applications, telemetry systems are traditionally used to provide a front end for processing Control Center data. Control Center operations dictate the content and processing requirements of the telemetry data to enable the control center personnel to make proper decisions concerning the operation of their space vehicle. Unfortunately many anomalous operational scenarios do not arise during control center checkout procedures which are designed to test the functionality of the Control Center equipment. However, an interactive telemetry simulation, which involves producing telemetry data using real-world formats and data rates, can create many of the situations control center personnel may encounter. A host computer is used to drive a telemetry system which in turn produces simulated vehicle data. As a result, a telemetry simulation can not only verify the functionality of the Control Center hardware and software, but also validate Control Center procedures and train Control Center personnel in the process.
    • Processing Real-Time Telemetry with Multiple Embedded Processors

      BenDor, Jonathan; Baker, J. D.; Dovetail Systems Corporation; SEMCO (International Foundation for Telemetering, 1994-10)
      This paper describes a system in which multiple embedded processors are used for real-time processing of telemetry streams from satellites and radars. Embedded EPC-5 modules are plugged into VME slots in a Loral System 550. Telemetry streams are acquired and decommutated by the System 550, and selected parameters are packetized and appended to a mailbox which resides in VME memory. A Windows-based program continuously fetches packets from the mailbox, processes the data, writes to log files, displays processing results on screen, and sends messages via a modem connected to a serial port.
    • TWARSES The Two Wire Automatic Remote Sensing and Evaluation System

      Dahl, Ernest A.; Naval Surface Warfare Center (International Foundation for Telemetering, 1994-10)
      The Two Wire Automatic Remote Sensing and Evaluation System (TWARSES) automatically transmits and evaluates information (data) from remote sensors on a common two wire buss. In addition the system presents automatic evaluation and alarms, which provide both location data and sensor readout data of the monitored area. This system is a stand-alone modular system in which a common two wire line installed bow-to-stern and top-to-bottom, connects, integrates, evaluates, and powers a multiplicity of sensors. The United States Navy uses this system to provide safety and survivability by monitoring environmental gases, liquid levels, and power, temperature, and humidity levels on ships and in office buildings. The automatic monitoring system operates in a manner similar to an automatic, multiscriber, party-line telephone system. The system is controlled by the Scanner/Display unit which interrogates each of the 150 possible sensors according to the program stored in a microprocessor. This patented system provides a separate address for each sensor transponder, permitting all of the transponders to be simply connected in parallel across a common, twisted pair transmission line. The interrogating signal is also used to provide power (6V - 2mA) for the sensor transponders and their associated sensors. This further simplifies the system by eliminating the need for a separate source of power at each sensor location. Each sensor is interrogated with a 15-bit sequence which specifies: (1) the address of the sensor which is to reply, (2) the parameter to be reported (e.g. voltage, temperature, humidity, etc.) And (3) the desired precision (which sets the length of the reply). The interrogation is transmitted as frequency shift-keyed signal. Among the various types of interrogation signals which could be used (AM, FM, etc.) frequency shift-keying (FSK) was selected because:
    • Binary PCM/FM Tradeoffs Between Spectral Occupancy and Bit Error Probability

      Law, Eugene L.; NAWCWPNS (International Foundation for Telemetering, 1994-10)
      The bit rates of telemetry systems are increasing rapidly. Higher bit rates occupy more spectra and result in decreased link margin. The major signal parameters that affect the spectral occupancy and bit error probability (BEP) of binary pulse code modulation (PCM)/frequency modulation (FM) signals are the bit rate, code, premodulation filter, and peak deviation. The measured spectral occupancy is also affected by the spectrum analyzer (or other measurement equipment) settings. Additional parameters that affect the BEP include the receiver intermediate frequency (IF) filter, the FM demodulator, and the bit detector. This paper will present the effects of these parameters on the measured 99% and -60 dBc bandwidths and the BEP of binary PCM/FM telemetry signals. Normalized BEP and bandwidth curves will be presented.