• Hypermedia and Expert Systems Applied to Space Vehicle Monitoring & Control

      Bost, J. D.; Le, T. C.; Mangan, P. K.; Meloan, M. D.; Sutton, S. A.; Turner, S. R. (International Foundation for Telemetering, 1989-11)
      The Defense Meteorological Satellite Program (DMSP) weather satellite supports worldwide defense operations by the acquisition of global visual and infrared cloud data and other specialized meteorological, oceanographic, and solar data. In support of DMSP, prototypes are currently under development that will demonstrate the viability of expert systems, real-time graphics, and hypermedia-based information navigation for space vehicle monitoring & control.
    • Data Rate Reduction Using a Digital Anti-Aliasing Filter

      Lee, Kyong H.; Maschhoff, Robert H.; Gulton Data Systems (International Foundation for Telemetering, 1989-11)
      In this paper we explore the limits of data rate or sample rate reduction that can be accomplished by sharp cutoff band limiting filters in a PCM data acquisition system. The results with practical analog filtering techniques are compared with those possible with digital filtering techniques. A typical 2:1 reduction in telemetry bit rate is shown to be practical using digital vs analog techniques. The resultant sample rates as low as 2.5 times the filter cutoff frequency has implications in the reconstruction algorithms which are also discussed. It is shown that by using practical and appropriate interpolation techniques or sample rate multiplication processes the data fidelity can be preserved. Thus the data user is assured that no information is being lost.
    • Advanced Orbiting Systems: A Standard Architecture for Space Data Communications

      Hooke, Adrian J.; California Institute of Technology (International Foundation for Telemetering, 1989-11)
      The first thirty years of civilian space exploration were characterized by a series of individual missions, focussed towards specific goals and servicing small and close-knit user communities. Spacecraft (constrained by power, weight and volume considerations) were customized towards mission objectives. Their data handling and communications systems were primarily built for simplicity and robustness, and displayed little commonality from mission to mission. All of the easy space missions have now been flown. As we move into the 1990s, requirements exist for complex missions involving Earth observation, exploration and a more permanent human presence in space. Internationalization of these missions is inevitable as a means to distribute and share costs, and to increase their political stability. Automation of their data handling systems is essential to support reliable, low cost operations. Responding to this environment, the Consultative Committee for Space Data Systems (CCSDS) was formed in 1982 to develop and promote a full suite of internationally standardized space data communications protocols. The first set of recommended standards, covering the data handling requirements of conventional free-flying scientific spacecraft, was finalized in 1986. Using the international space station "Freedom" program (a cooperative venture between the US, Europe, Canada and Japan) as a requirements model, the CCSDS has now extended its suite of recommended standards to cover "advanced orbiting systems" such as unmanned and man-tended Earth observation platforms, new space transportation systems, and manned laboratories. These systems, which operate as longterm orbiting facilities and therefore have changing user communities, produce prodigious rates and volumes of data including digitized video and audio. For the first time, the orbiting systems will use local area networks for internal data transfer. On the ground, they will interface with networks designed for worldwide Open Systems Interconnection (OSI). This paper reviews the standard data handling service architecture which has been developed by CCSDS. It describes the communications protocols that are recommended for the networked transfer of space mission data, and focuses on the unique requirements of transmitting many different data types through weak signal, noisy space channels at rates which routinely may reach many hundreds of megabits per second.

      Dunn, Wiley E.; Fairchild Weston Systems Inc. (International Foundation for Telemetering, 1989-11)
      Although magnetic recording devices employing rotary head technology have been around for many years, specific products were not developed with the bit error performance to satisfy the instrumentation recorder needs of the telemetry community. Only recently have a number of new products and new product development programs materialized which offer positive indications that telemetry systems will soon benefit from the higher data rates and storage capacities. The lack of standards in development of rotary head technology has led to development of a variety of design approaches by various manufacturers and system designers. If this trend continues, the telemetry community will not enjoy the media compatibility which has contributed so much to the success of the IRIG instrumentation recorder. The ability to remove a tape recorded on one vendors recorder and replay the tape on a different ground station containing a second vendors recorder is a capability that should be retained with the advent of the new machines. Two standards have evolved defining tape characteristics and the format of information on tape for instrumentation rotary head recorders. For the instrumentation tape media to be truly transportable between telemetry ground stations, standard signal and data formal interfaces must also be developed.
    • Software for the Concurrent Based Telemetry Data Handling System (TDHS)

      Bosik, Edward R.; Hutchinson, Michael P.; White Sands Missile Range; Fairchild Weston (International Foundation for Telemetering, 1989-11)
      The TDHS, designed and built for WSMR (White Sands Missile Range), is hosted by a Concurrent 3280 Processor. The TDHS software is a combination of new software designed specifically for this system and conversion of software that Fairchild Weston offers as standard products on other host computers. The system software is based on a menu system and provides a friendly user interface. The software supports the latest EMR products (including an 8715 Preprocessor and an 8470 Digital Discriminator), intercomputer data transfer and very high speed storage of data to disk and tape. TDHS also provides quick-look data display during real-time on strip charts and Concurrent based displays. Data processed by the Concurrent host can be sent back to the 8715 for distribution in the same manner as the incoming telemetry data. Immediately after data acquisition all data can be viewed on the color graphic and alphanumeric terminals.
    • Third-generation Advances in Thermal Printhead-based Chart Recorders

      Gaskill, Dave; Astro-Med, Inc. (International Foundation for Telemetering, 1989-11)
      A brief recap of the effect thermal printhead technology has had on the common 8-channel strip chart recorder, followed by a summary of second and third generation products and their envolving capabilities. How these new instruments are being accepted and used by telemetrists and ground station managers who are faced with bigger tasks and shrinking budgets. A study of how today's telemetry professionals are shaping the 8-channel recorders of tomorrow, and the new capabilities they will bring.
    • Distributed Microprocessing of PCM Telemetry Provides Unlimited Real Time Analysts Displays

      Johnson, James F.; The Aerospace Corporation (International Foundation for Telemetering, 1989-11)
      Invariably, during the launch of large scale spacecraft, there is a need to provide large numbers of analysts with real time telemetry displays. This is especially true of "one-of-a-kind" or "first-of-a-series" spacecraft. These analysts have a wide range of needs and are specialists in many diverse disciplines. The problem is how to divide up a high speed telemetry stream in such a way that each analyst has access to the measurements of interest. Many large scale systems have been built to do this, but are often limited as to the number of displays that can be supported, and are easily swamped by data requests. This paper presents a microcomputer architecture which supports an unlimited number of individual displays and provides each analyst with access to all measurements from which data of interest may be chosen at will, with no affect on system throughput. In addition, the system is inexpensive, very flexible, and relatively easy to implement.
    • Programming Code-Modulator and Demodulation-Decoder Suited to PCM Systems

      Daqing, Huang; RPV Research Institute; Nanjing Aeronautical Institute (International Foundation for Telemetering, 1989-11)
      In order to suit the development of computer telemetry systems, we have developed the intelligent code-modulator and demodulation-decoder. In hardware, they consist of a monolithic processor and some high-integrated devices. Different code or decode ways and several subcarrier modulation or demodulation systems can be varied by carrying out corresponding software programs. In this paper, the equipments' hardware constructions and software cnarts and their main principles are presented.
    • The Application of RISC Architectures to Real-Time Telemetry Processing

      Malatesta, William A.; Veda Incorporated (International Foundation for Telemetering, 1989-11)
      The number and types of processes carried out on telemetered data in real time have increased in direct proportion to the available processing speeds. Operations following decommutation in the data pipeline are often referred to generically as Engineering Units Processing (EUP). Examples of the types of functions typically performed by an EUP are data compression, polynomial conversion, and with the advent of message data, desyllabification. Real-time telemetry processing, such as EUP, has traditionally been done on bitslice processors, primarily because they possessed the speed required to maintain pace with the relatively high data rates. As data rates continue to increase, the need for bitslice processors with even higher processing speeds would seem to be even more pressing. However, in recent years RISC (Reduced Instruction Set Computer) based microprocessors have been developed that approach bit-slice processing rates and possess certain advantages. The advantages of a RISC based approach to real-time telemetry processing include ease of programming, shorter design and implementation cycles, and a direct path to speed increases as silicon processing technology advances. In addition, the streaming nature of the data to be operated on, and the EUP requirements generate a multi-branched program structure creating the potential for a high degree of optimization within a pipelined processor architecture. While most RISC applications are currently programmed in assembly language to take full advantage of the hardware, it is expected that improvements in optimizing compilers in the future will further enhance the position of RISC with respect to bit-slice processing.

      Sharp, Kirk; Thompson, Lorraine Masi; Naval Ocean Research & Development Activity; LMT Concepts (International Foundation for Telemetering, 1989-11)
      The Naval Ocean Research and Development Activity (NORDA) has adapted the Loral Instrumentation Advanced Decommutation system (ADS 100) as a portable maintenance system for one of its remotely deployable buoy systems. This particular buoy system sends up to 128 channels of amplified sensor data to a centralized A/D for formatting and storage on a high density digital recorder. The resulting tapes contain serial PCM data in a format consistent with IRIG Standard 106-87. Predictable and correctable perturbations exist within the data due to the quadrature multiplexed telemetry system. The ADS 100 corrects for the perturbations of the telemetry system and provides the user with diagnostic tools to examine the stored data stream and determine the operational status of the buoy system prior to deployment.
    • Simulating Satellite Telemetry

      Blasdel, Arthur N., Jr.; Ford Aerospace Corporation (International Foundation for Telemetering, 1989-11)
      Ford Aerospace Corporation has been investigating the use of intelligent systems to automate space mission support functions since the early 1980's. A product of this research is Paragon, a model-based development environment for intelligent systems. Paragon has been used to develop functional models of satellites that are robust in their abilities to represent satellite behavior. The models have been used to simulate both nominal and anomalous temporal behavior. This paper describes our simulation approach and how the telemetry output from the system can be used during training and rehearsals to provide a closed-loop, interactive response to a wide variety of scenarios.
    • Trends in Recording Capabilities For The ‘90’s’

      Hoover, J.H.; GE Aerospace (International Foundation for Telemetering, 1989-11)
      As sensor bandwidths increase and the amount of information gathered increases, higher capacity storage devices will be required as well as increased capture/transmission/reproduce data rates. Both collection/capture sites (with more sensors and wider bandwidths) and link receive/distribution sites will need to be upgraded to accommodate high transmission rates, provide rate matching for capture/dissemination/processing and provide higher capacity storage. These trends and recorder solutions are forecast as natural evolution of the state-ofthe-art. Extended performance (high data rate/high capacity) tape recorders will be discussed as applicable to satelliteto-ground communication, space platform experimental data gathering, reconnaissance, ASW sonar, radar and data processing systems.

      Taylor, Larry M; Loral Instrumentation (International Foundation for Telemetering, 1989-11)
      Recent developments in telemetry have resulted in an increased variety of data sources. As a result, data streams are incorporating such complexities as embedded asynchronous data streams, packets, and multiple formats. These data streams must be acquired and processed in real-time by telemetry ground stations. Most modern telemetry systems use a distributed architecture to accomplish these complex decommutation and preprocessing tasks. It is usually desirable to verify the data base setup and functional operation of the system before critical tests, as well as during test development. Most of the telemetry simulator products available today can do only a very limited simulation of the incoming data stream. This often fails to exercise many key components of the system. A new product will be described which can simulate a data stream with multiple formats, embedded asynchronous data streams, unlimited special words, and other useful functions. This product will enable the user to perform a more complete test of all of the components of the telemetry system.
    • Adaptation of a Loral ADS 100 as a Remote Ocean Buoy Maintenance System

      Sharp, Kirk; Thompson, Lorraine Masi; Naval Ocean Research & Development Activity; LMT Concepts (International Foundation for Telemetering, 1989-11)
      The Naval Ocean Research and Development Activity (NORDA) has adapted the Loral Instrumentation Advanced Decommutation system (ADS 100) as a portable maintenance system for one of its remotely deployable buoy systems. This particular buoy system sends up to 128 channels of amplified sensor data to a centralized A/D for formatting and storage on a high density digital recorder. The resulting tapes contain serial PCM data in a format consistent with IRIG Standard 106-87. Predictable and correctable perturbations exist within the data due to the quadrature multiplexed telemetry system. The ADS 100 corrects for the perturbations of the telemetry system and provides the user with diagnostic tools to examine the stored data stream and determine the operational status of the buoy system prior to deployment.
    • Small Intercontinental Ballistic Missile Telemetry Processing System

      Woodham, Milt; Kelley, A. L.; Martin Marietta Corporation; Fairchild Weston Data Systems (International Foundation for Telemetering, 1989-11)
      Development of the Small Intercontinental Ballistic Missile (SICBM) requires a versatile Telemetry Processing System to support the various tests throughout the development. These test requirements created a need for high-speed data processing and display for real time decisions. These requirements were driven by the need to reduce development time and cost of the small ICBM. Martin Marietta was also interested in an off-the-shelf system (hardware and software). The system had to be menu-driven and user-friendly. Martin Marietta entered into a contract with Fairchild Weston Systems Inc. to supply five (5) of these systems, known as Telemetry Processing Systems (TPS). This paper defines the TPS System hardware and software capabilities and how it is being used to support the small ICBM testing.
    • RTDAP: Real-Time Data Acquisition, Processing and Display System

      Dahan, Michael; Instrumentation and Telemetry Systems (International Foundation for Telemetering, 1989-11)
      This paper describes a data acquisition, processing and display system which is suitable for various telemetry applications. The system can be connected either to a PCM encoder or to a telemetry decommutator through a built-in interface and can directly address any channel from the PCM stream for processing. Its compact size and simplicity allow it to be used in the flight line as a test console, in mobile stations as the main data processing system, or on-board test civil aircrafts for in-flight monitoring and data processing.
    • Low-cost, short-term development or high-data-rate, multi-stream, mulit-data type telemetry acquisition/processing system using an off-the-shelf integrated Telemetry Front End.

      Carter, Bruce; Scoughton, Troy; New Mexico State University (International Foundation for Telemetering, 1989-11)
      This paper explores the effects the new breed of off-theshelf integrated telemetry front end (TFE) packages have on the cost and schedule of the development cycle associated with real-time telemetry acquisition/processing systems. A case study of an actual project involving replacement of the Holloman AFB sled track telemetry processing system (TPS) with a system capable of simultaneously supporting up to twenty (20) asynchronous data streams is profiled. Notable among the capabilities of the system are; support for PCM, PAM, FM, IRIG and Local time streams; incoming data rates up to 10 Megabits/sec/stream; data logging rates over 16 MegaBytes/sec and the use of local area networks for distribution of data to real-time displays. To achieve these requirements within a manageable cost/schedule framework, the system was designed around an integrated TFE sub-system. Comparisons are drawn between several aspects of this projects development and that of an earlier developmental system which was completed by PSL within the last 16 months.

      Gilje, Harold B.; Gravel, Arthur J.; AYDIN VECTOR DIVISION (International Foundation for Telemetering, 1989-11)
      The Telemetry Group of the Range Commanders Council has provided suggested standards for transmission of telemetry data. These standards were necessary to promote compatibility of operational equipment at the respective Test and Evaluation ranges. For digital transmission, the applicable standards define the frame and word formats necessary for range compatibility. These standards were developed for acquisition of multiple analog and bi-level signals and provided a relatively straight forward means of developing an aggregate, time-division multiplexed (TDM), serial, data stream which includes the information necessary to reconstruct the signals at the ground station prior to analysis. The Inter-Range Instrumentation Group (IRIG) formats are, by design, periodic and form a matrix of Awords@ which are preassigned to each and every signal being encoded and transmitted. As all the original information is continuous in nature, the encoder must sample each of the channels in their proper sequence and place the sampled data in it’s respecitve time slot. This paper will address some of the buffering techniques used to transmit data in an integrated IRIG format. We will then address an alternate solution to transmitting computer data for ground based analysis and processing, i.e., transmission of data using commercial type modems.

      NAGARAJ, S.R.; RAJANGAM, R.K.; ISRO SATELLITE CENTRE (International Foundation for Telemetering, 1989-11)
      The Vector cardiography is the 3 dimensional study of Electrocardiographic responses of the human heart. A Vector cardiograph (VCG) instrument was designed and developed to monitor the Cardiographic responses of the Indian payload specialist under zero G conditions in the US Space Shuttle during the scheduled INSAT-lC launch. Accordingly the proposal made by Department of Space for using the vector cardiograph measurement in the Space Shuttle was accepted. A VCG unit was developed under the joint collaboration of HAL, Hyderabad and ISAC-ISRO. This paper brifly describes the design aspects of the VCG instrument, the qulification tests conducted on the same for space application and the final test results obtained during the process. Basically the instrument was built around a Hybrid Instrumentation amplifier and other interfaces for recording the signal into an audio taperecorder.
    • Advanced Concepts for Telemetry Data Systems

      Pritchard, James A.; National Aeronautics and Space Administration (International Foundation for Telemetering, 1989-11)
      Current telemetry data processing systems capabilities will have to be improved by as much as three orders of magnitude in order to handle the expected data rates of the Space Station era. National Aeronautics and Space Administration (NASA) processing systems can currently process telemetry data at an average input rate of about 100K bits per second while Space Station era data rates will average about 100M bits per second and could have peak rates of up to 1200 M bits per second. In order to meet the challenge of developing telemetry systems for processing high rate data at a reasonable cost, data processing and distribution systems must be data driven as opposed to being resource scheduled. If a system is to be data driven, data structures must contain a mechanism for routing of the data to its intended destination. Packet telemetry systems have been developed for the purpose of processing and routing telemetry data at higher rates than conventional time division multiplexed systems. Packet telemetry data standards are being developed by the international Consultative Committee for Space Data Standards (CCSDS) in order to facilitate development of packet telemetry systems both within NASA and international space agencies as well as for inter-agency cross support situations. These CCSDS Advanced Orbiting Systems (AOS) standards specify the overall architectural framework of future packet telemetry systems. The CCSDS AOS standard defines a CCSDS Principal Network (CPN) which covers the on-board, space link and ground systems and provides for asynchronous (e.g., Telemetry and Internetworking) and isochronous (e.g., Audio and Video) data transport services utilizing CCSDS Packets and Virtual Channels. In order to achieve efficient use of the limited resources of the space link, CCSDS Packets are multiplexed on to CCSDS Virtual Channels for transmission through the space link. This paper will mainly discuss changes to ground telemetry processing systems currently in use (such as the Packet Processor (PACOR) System), future systems under development (such as the Space Station Information System(SSIS) and the Customer Data Operations System (CDOS)), and how the CCSDS standards relate to these systems.