• 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.
    • Unix and the Real-Time Telemetry System

      Waggener, William N.; Fairchild Weston Data Systems (International Foundation for Telemetering, 1989-11)
      Since the first computer-based telemetry systems were designed in the mid-1960's, the operating system has been the nemesis of the system software designer. The requirement to acquire telemetry data at high rates, in real time, without loss, is in direct conflict with the direction computer operating systems have taken over the last two decades. The "lean and mean", single user operating systems of the 1960's have been replaced by multi-tasking, multiuser systems which emphasize multiple applications at the expense of real-time performance. Recently, there has been enormous interest in hosting real-time telemetry systems under the UNIX operating system. From an applications standpoint UNIX has much to offer the user but it certainly complicates the life of the real-time system software designer. In this paper, a critical look is taken at the role of the operating system in a real-time telemetry system with particular emphasis on the use of UNIX POSIX and realtime extensions.
    • TELEMETRY DATA PROCESSING AT WHITE SANDS MISSILE RANGE

      Ogaz, Juan A.; Data Sciences Division, National Range Operations (International Foundation for Telemetering, 1989-11)
      Prior to 1985 the National Range had, for a number of years, serious and recurring mission support problems with the IBM 360 Telemetry Data Processing System due to equipment reliability and obsolescence of the system which was installed in 1968. These problems became particularly acute when higher data rate requirements and the need for reliable telemetry data processing dictated that prompt and unusual action was necessary if WSMR was to continue to provide telemetry data processing support. Realizing that the above cited problems of reliability and obsolescence would continue in detriment to the mission of WSMR, Department of Defense (DOD) and the nation, coupled with the loss of thousands of dollars in reimbursables due to WSMR’s inability to support missile test requirements, the Systems Engineering Branch was tasked by the Director of National Range to lead a study, and propose and implement solutions to meet current and future requirements in telemetry data processing support. With the explosion in PCM data rates, it had become obvious that WSMR could not continue to upgrade existing systems and meet the demands of the future. More data parameters at higher data rates were being processed in PCM, FM, and PAM. Telemetry formats were becoming more complicated, such as embedded asynchronous subcomms and dynamic format changes. More real-time decisions had to be made for mission safety, verification of location, and mission success. WSMR needed a more versatile system that would synchronize, process and display higher data rates with more accuracy than it had at this time. This paper describes a historical perspective of steps WSMR has taken to satisfy present and future test vehicle telemetry data processing requirements.
    • DATA DISTRIBUTION In The TELEMETRY GROUND STATION OF THE 1990’s

      Strock, O.J. (Jud); Fairchild Weston Systems, Inc. (International Foundation for Telemetering, 1989-11)
      For as long as telemetry has been used in scientific research, users have asked for transmission of more data points at higher data frequencies. Now, the increased complexity of vehicles under test and the presence of data from one or several computer systems on a vehicle has further increased the rate and format complexity of a typical telemetry data stream. To accommodate higher data rates and increased complexity, many telemetry ground stations use distributed processing techniques, typically employing a hardware preprocessor, a host computer, and one or more intelligent display stations. While this distribution of power potentially enhances data throughput rates, it imposes new demands on data distribution networks within the processing area, and the full potential of the processors cannot be met until these demands have been met. This paper looks first at system architecture of the typical ground station, and how this architecture and telemetry data rate capability have progressed during the past 20 years. Then it looks at the data distribution requirement in a modern telemetry ground station, explores possible solutions to improve throughput rates, and describes a set of solutions for typical system applications in the next few years.
    • MIL-STD-1553 Data Acquisition System

      Landry, Michael; Loral Conic (International Foundation for Telemetering, 1989-11)
      The Range Commanders Council recently added a chapter to IRIG 106-86 which describes a standard for acquisition of MIL-STD-1553 traffic flow. A system has been developed which monitors bus traffic using the format described in the standard for encoding. In addition to bus data, PCM analog channels can be inserted into the telemetry steam. Due to the high bandwidth of the telemetry stream, real-time ground processing of the 1553 data is difficult. Therefore, a limited number of selective measurements taken from the bus traffic are available at fixed positions in the telemetry format for real-time monitoring of critical parameters. A discussion of hardware, software, encoding, and testing will be presented.
    • A RE-ENTRY METERING DATA PROCESSING SYSTEM

      NONG, CHEN; FU-TANG, ZHANG; Xinan Electronic Engineering Institute (International Foundation for Telemetering, 1989-11)
      This article introduces a system for processing data from re-entry flying object’s internal telemetry and its flying trace. That system receives data from various demodulators in re-entry synthetic metering systems, stores those data into disk in realtime and processes part of the data and displays the results in realtime(such as strip picture, parameter curve, value table, internal time-base, alarm and so on). Further processing may be completed afterwards using stored data. Multi-layer intelligent buffer and shared storage techniques are adopted in the system to get a high speed and large capacity data link between demodulators and super-microcomputer. The system’s hardware and software design and its operation are described in the article.
    • 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.
    • FRAME RATE REDUCTION IN VIDEO TELEMETRY SYSTEMS

      SCHAPHORST, RICHARD A.; DEUTERMANN, ALAN R.; DELTA INFORMATION SYSTEMS, INC. (International Foundation for Telemetering, 1989-11)
      In video telemetry systems the transmitted picture rate, or temporal resolution, is a critical parameter in determining system performance as well as the transmitted bit rate. In many applications it is important to transmit every TV frame because the maximum temporal resolution must be maintained to analyze critical events such as an encounter between a missile and a target. Typical transmission bit rates for operation at these picture rates are 5.0 to 10.0 mbps. In other cases the frame rate can be reduced slightly to 15 or 7.5 frames/sec. without significantly reducing the value of the output video. At these frame rates it is still possible to sense the continuity of motion although some jerkiness may appear on rapidly moving objects. At these reduced frame rates the transmitted bit rate can go as low as 1.0 mbps. There is a third class of video telemetry applications where the scene is changing very slowly, and it is permissible to transmit a series of still pictures at very reduced rates. For example one picture can be transmitted every second at a transmission bit rate of 100 Kbps. The purpose of this paper is to examine operation of the standard video coding system (Range Commander Council Standard RCC 209) at conventional frame rates as well as a wide range of reduced frame rates. The following section describes the basic digital TV system which employs the standard codec. Two particular modes of operation are discussed: (1) those which reduce the frame rate by a fixed amount and vary the spatial resolution according to the complexity of the TV image; (2) those which maintain the spatial resolution at a fixed level and automatically vary the temporal resolution according to the complexity of the image. A tradeoff analysis is presented illustrating the interaction of spatial resolution, temporal resolution, and transmission bit rate. A video tape is described and presented illustrating system operation at a wide range of frame rates. Finally, conclusions are drawn.
    • MEASURING THE PERFORMANCE OF TELEMETRY VIDEO CODECS

      COMEAU, CHARLES; FISHER, JOSEPH; DELTA INFORMATION SYSTEMS (International Foundation for Telemetering, 1989-11)
      The Range Commanders Council has recently approved standard RCC 209-88 which defines the compression algorithms and communications frame structure for telemetry video coders. The compression algorithm is very flexible permitting the TV image to be encoded using either 2 bit or 3 bit DPCM, sub-sampled or not, coarse of fine quantizations. Any combination of these modes of operation can be selected and changed on a line-to-line basis. Each manufacturer of the video encoder will develop his own algorithms for selecting various modes of operations as the complexity of the picture changes. Clearly the picture quality produced by the encoder/decoder system will depend strongly on the mode control algorithm in the encoder. The purpose of this paper is to describe new test procedures which are required to measure the performance of encoders designed to meet RCC 209-88.
    • UNIX AND THE REAL-TIME TELEMETRY SYSTEM

      Waggener, William N.; Fairchild Weston Data Systems (International Foundation for Telemetering, 1989-11)
      Since the first computer-based telemetry systems were designed in the mid-1960’s, the operating system has been the nemesis of the system software designer. The requirement to acquire telemetry data at high rates, in real time, without loss, is in direct conflict with the direction computer operating systems have taken over the last two decades. The Alean and mean@, single user operating systems of the 1960’s have been replaced by multi-tasking, multiuser systems which emphasize multiple applications at the expense of real-time performance. Recently, there has been enormous interest in hosting real-time telemetry systems under the UNIX operating system. From an applications standpoint UNIX has much to offer the user but it certainly complicates the life of the real-time system software designer. In this paper, a critical look is taken at the role of the operating system in a real-time telemetry system with particular emphasis on the use of UNIX POSIX and realtime extensions.
    • An Integrated Telemetry Decommutation and Display System

      Loeser, Jean-Marc; Schlumberger Industries (International Foundation for Telemetering, 1989-11)
      This paper describes an integrated architecture providing in a single box the complete functions of a telemetry system. The 3700 Decommutator can perform data synchronization, tagging and merging, as well as processing and output in various forms, on different input streams simultaneously. Most functions of larger telemetry systems are implemented here at the card level. Being based on a VME bus architecture, the unit is very modular and can be configured differently according to the specific requirements of particular test programs. The 3700 Decommutator can be used as a stand-alone station, providing Aquick-look@ monitoring of real time data to different independent users, or as a computer front-end in a larger system. It is a compact unit, easily transportable. Front-end functions and product features are presented, illustrating the large number of applications of the unit. The variety of display formats that can be created and rapidly modified by users is described. Flexibility in set-up and operation is then discussed, in order to demonstrate how a simple database structure matches a modular hardware architecture, resulting in a userfriendly unit allowing rapid and easy changes in mission set-up.
    • Systems Engineering and Integration of Control Centers in Support of Multiple Programs

      Miller, David N.; National Aeronautics and Space Administration (International Foundation for Telemetering, 1989-11)
      The Multiprogram Control Center (MPCC) at the Johnson Space Center (JSC) was envisioned as a means of satisfying the ground control requirements for complex Space Transportation System (STS) payloads and unmanned vehicles. This paper will describe the role and characteristics of the MPCC and its relationship to the STS Mission Control Center (MCC). It will also reveal significant problems encountered and useful solutions to some fairly generic problems. It will discuss the current direction of control center technology and vendor opportunities from the MPCC's perspective. It will conclude with specific lessons learned thus far in the MPCC project.
    • Telemetry Data Processing at White Sands Missile Range

      Ogaz, Juan A.; White Sands Missile Range (International Foundation for Telemetering, 1989-11)
      Prior to 1985 the National Range had, for a number of years, serious and recurring mission support problems with the IBM 360 Telemetry Data Processing System due to equipment reliability and obsolescence of the system which was installed in 1968. These problems became particularly acute when higher data rate requirements and the need for reliable telemetry data processing dictated that prompt and unusual action was necessary if WSMR was to continue to provide telemetry data processing support. Realizing that the above cited problems of reliability and obsolescence would continue in detriment to the mission of WSMR, Department of Defense (DOD) and the nation, coupled with the loss of thousands of dollars in reimbursables due to WSMR's inability to support missile test requirements, the Systems Engineering Branch was tasked by the Director of National Range to lead a study, and propose and implement solutions to meet current and future requirements in telemetry data processing support. With the explosion in PCM data rates, it had become obvious that WSMR could not continue to upgrade existing systems and meet the demands of the future. More data parameters at higher data rates were being processed in PCM, FM, and PAM. Telemetry formats were becoming more complicated, such as embedded asynchronous subcomms and dynamic format changes. More real-time decisions had to be made for mission safety, verification of location, and mission success. WSMR needed a more versatile system that would synchronize, process and display higher data rates with more accuracy than it had at this time. This paper describes a historical perspective of steps WSMR has taken to satisfy present and future test vehicle telemetry data processing requirements.
    • 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.
    • 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.
    • Rotary Head Recorders in Telemetry Systems

      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.
    • TELEMETRY DATA STORAGE SYSTEMS TECHNOLOGY FOR THE SPACE STATION FREEDOM ERA

      Dalton, John T.; NASA/Goddard Space Flight Center (International Foundation for Telemetering, 1989-11)
      NASA’S Space Station Freedom and the Earth Observing System, due to be operational in the mid-1990’s, will provide scientists the vehicles to deploy an unprecented number of data producing experiments, including advanced imaging instruments with high spatial and spectral resolution. Peak down-link data rates are expected to be in the 500 megabit per second range, and the daily volume of science data could reach 2.4 terabytes. Such startling requirements have stimulated development efforts in high rate on-board recorders, and inspired an internal NASA study to determine if economically viable data storage solutions are likely to be available to support the ground data transport segment. This paper summarizes the mission and system drivers for telemetry data recording and storage capabilities, and provides an overview of NASA efforts to prototype advanced storage systems.
    • AN ADVANCED TELEMETRY SIMULATOR

      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.
    • 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.
    • Research of Diversity Receive for Re-entry Telemetry System

      ji-San, Lu; Beijing institute of special mechanical and Electrical Devices (International Foundation for Telemetering, 1989-11)
      This Paper is based on results of radio signal propagation tests that are performed on sea and ground. Other test results also are referred. Practice of polarity diversity. space diversity and frequency diversity used for re-entry telemetry system is discussed briefly. The achieved effect and existing problems in using diversity technology is analyzed. Finally, the diversity technology is evaluated with respect to engineering.