Bain, R. S.; Veda Systems Incorporated (International Foundation for Telemetering, 1992-10)
      Modern telemetry systems collect large quantities of data at high rates of speed. To support near real-time analysis of this data, a sophisticated data archival system is required. If the data is to be analyzed during the test, it must be available via computer-accessible peripheral devices. The use of computer-compatible media permits powerful “instant- replay-type” functions to be implemented, allowing the user to search for events, blow-up time segments, or alter playback rates. Using computer-compatible media also implies inexpensive COTS devices with an “industry standard” interface and direct media compatibility with host processing systems. This paper discusses the design and implementation of a board-level archive subsystem developed by Veda Systems, Incorporated.

      Mills, George T.; Naval Air Warfare Center - Weapons Division (International Foundation for Telemetering, 1992-10)
      A simple technique to convert 675 and 875 line video to the more common 525 line rate is presented. The higher density 875 and 675 videos are stored and rescanned at the 525 line rate to produce a video signal that is essentially the same video signal that would have originally been generated by a 525 line video sensor (camera).

      Bryars, John; Smith, Gregory S.; Jaycor; Trilogy Microsystems (International Foundation for Telemetering, 1992-10)
      A Digital Output Recorder (DOR) system was developed by JAYCOR under contract to Defense Nuclear Agency (DNA) for the recording of high-speed digital data from test hardware exposed to radiation during an Underground Nuclear Test conducted at the Nevada Test Site (NTS) in 1991. Electronics hardware for the system is based on the well-supported Versa Module Europe (VME) bus which has become an industry standard for digital process and control systems. The system collects, identifies, and telemeters the data from several interfaces using the VME bus to a common data collection point above ground. The system was designed with built-in flexibility and expandability to meet digital data recording requirements on future underground tests (UGTs).

      Larson, P. T.; Sheaffer, D. A.; Sandia National Laboratories (International Foundation for Telemetering, 1992-10)
      Our telemetry department has an application for a data categorization/compression of a high speed transient signal in a short period of time. Categorization of the signal reveals important system performance and compression is required because of the terminal nature of our telemetry testing. Until recently, the hardware for the system of this type did not exist. A new exploratory device from Intel has the capability to meet these extreme requirements. This integrated circuit is an analog neural network capable of performing 2 billion connections per second. The two main advantages of this chip over traditional hardware are the obvious computation speed of the device and the ability to compute a three layer feed-forward neural network classifier. The initial investigative development work using the Intel chip has been completed. The results from this proof of concept will show data categorization/compression performed on the neural network integrated circuit in real time. We will propose a preliminary design for a transient measurement system employing the Intel integrated circuit.

      Perschy, James A.; Johns Hopkins University (International Foundation for Telemetering, 1992-10)
      The digital processing within the radar altimeter on board the TOPEX satellite to obtain science and engineering telemetry is described. The application of the Fourier transform, a second order tracking loop, waveform compression, and telemetry formatting is required.
    • Applications of Type-I Hybrid-ARQ Error Control

      Rice, Michael; Brigham Young University (International Foundation for Telemetering, 1992-10)
      Hybrid-ARQ schemes employ the simultaneous application of error-detection and error-correction to combat transmission errors in a data communications system. In this way automatic repeat request (ARQ) and forward error correction (FEC) schemes are combined to offer effective error control. The key to implementation is the identification of reliability information in the FEC decoding process which is used to alter the FEC decoding algorithm. Under certain channel conditions, the realized efficiency is superior to that of either FEC or ARQ.

      Can, Ouyang; Chang-jie, Shi; Beijing Research Institute of Telemetry; Science and Technology Committee (International Foundation for Telemetering, 1992-10)
      Multiple processor architecture has been used in telemetry processing systems for many years. But how to evaluate the performance of such a system on telemetry data processing has not yet been adequately addressed. Utilizing a deterministic model, this paper tries to study the performance of multiple-processor telemetry data processing system. It demonstrates that the bus arbitration scheme, the ratio of processing time to communication time and the processing decomposition are the three important factors influencing the performance of such kind of systems. All the three factors are discussed. The results obtained have been applied to the design of the MSDDTS (Multi-Stream Data-Driven Telemetry System), a new generation multi-stream telemetry system in china, in order to gain the best cost-effectiveness.
    • Instrumentation Tape Recorders Using DAT Technology

      Heim, J.; JOSEF HEIM KG. (International Foundation for Telemetering, 1992-10)
      Instrumentation tape recorders have been known since the fifties. However, their requirements have undergone complete changes. More and more, the large “dinosaur type recorders” are superseded by new technologies, but when it comes to recording large data volumes over a long time the magnetic tape cannot be replaced by alternative recording methods. The following presentation will introduce magnetic tape units based on the 4 mm digital audio tape. This family of units has achieved large importance during recent years, since the DAT tape units have very small dimensions and can be used for all purposes. Depending on the application, analog and digital magnetic tapes are used. Thanks to the use of digital signal processors the system specifications could be improved to a considerable extent. Multi-channel analog recorders operate with digital signal processing. The transmission characteristics concerning amplitude and phase errors were improved such that the residual error can be neglected during daily metrology work. Furthermore, automatic calibration improves system accuracy and simplifies the units’ maintenance.

      Meier, Robert C.; Cincinnati Electronics Corporation (International Foundation for Telemetering, 1992-10)
      Some Telemetry systems today receive a binary phase shift keying modulation format. Typically, to demodulate BPSK requires using a carrier synchronizer followed by a bit synchronizer. Demodulation of BPSK can be accomplished using digital signal processing techniques to implement both synchronizers. This paper describes a digital system that demodulates a 16 KHZ, 2KBPS BPSK signal. In order to evaluate these techniques, the theory of operation was evaluated. Additionally, a computer simulation of the demodulator was developed. The computer simulation was implemented using Pascal. The techniques were optimized to give maximum performance while requiring minimum hardware and power in an actual implementation.

      Gelhaar, B.; Alvermann, K.; Dzaak, F.; Institute For Flight Mechanics (International Foundation for Telemetering, 1992-10)
      For research purposes on helicopter rotor acoustics a large data acquisition system called TEDAS (Transputer based Expandable Data Acquisition System) has been developed. The key features of this system are: unlimited expandability and sum data rate, local storage of data during operation, very simple analog anti aliasing filtering due to extensive digital filtering, and integrated computational power which scales with the number of channels. The sample rate is up to 50 kHz/channel, the resolution is 16 bit, 360 channels are realized now. TEDAS consists of blocks with 8 A/D converters which are controlled by one transputer T800. The size of the local memory is 4 Mbyte. Any number of blocks (IDAM = Intelligent Data Acquisition Module) can be combined to a complete system. Data preprocessing is done in parallel inside the IDAMs. As for 16 bit systems the analog antialiasing filtering becomes a dominant factor of the costs, delta sigma ADCs with oversampling and internal digital filtering are used. This produces an exact linear phase and a stop band rejection of -90 dB.

      Daniau, Marc; Millet, Philippe; SCHLUMBERGER Industries (International Foundation for Telemetering, 1992-10)
      DELTA 6000 System is a universal opened system for preprocessing, archival, realtime and offline analysis of telemetry data. The heterogeneous LAN architecture of DELTA 6000 comprises several front end ensuring the telemetry and high level realtime processing functions and several workstations for system control and display. The high communication level of DELTA 6000 enables an easy resource sharing as well as integration in customer environment. Easy operation through an efficient human interface and high versatility through the largest use of the most famous hardware and software industry standards are the major features of DELTA 6000. The more recent evolution of DELTA 6000 is the CE83 format realtime handling for use in European missiles programs.

      May, Anna Marie; Center for Space Telemetering and Telecommunication Systems (International Foundation for Telemetering, 1992-10)
      The aim of the present research is to develop a computationally efficient numerical model to analyze geostationary satellite availability from the lunar surface. This simulation includes a menu-oriented interface which facilitates user interaction and incorporates an animated visual display. The animated graphics display depicts the satellite constellation as the simulation progresses and aids in proper evaluation of the model. This simulation is general in configuration and allows for arbitrary input parameters for positioning satellites, specifying the rate of program execution, and specifying the sampling rate. A method of determining when the moon is visible to a geostationary satellite is presented. The effects of varying the sampling rate on the correct determination of the time window in which lunar-geostationary satellite visibility occurs is studied. Large time intervals yield misleading data while small time intervals slow the execution of the simulation. The optimum time interval which yields reliable data was shown to be thirty minutes.

      Hardwicke, K. R.; Applied Research Labs (International Foundation for Telemetering, 1992-10)
      The uncertainty in the gain of voltage controlled crystal oscillators (VCXOs) used in the implementation of certain analog phase-locked loops (PLLs) suggests some form of automatic tuning algorithm, both for pretuning and during operation. This paper proposes an adaptive PLL (APLL) algorithm to fill this need for PLLs used in the recovery of tones in noise. This algorithm makes use of a resonant error algorithm to remove the effects of VCXO noise, measurement noise, and parasitic poles. Both classical convergence theorems and robustness theorems that indicate the functionality of the proposed algorithm are given. Finally, the implementation of this algorithm is considered.

      Bossert, Kathleen B.; Loral Data Systems (International Foundation for Telemetering, 1992-10)
      Today’s telemetry preprocessing systems are often required to create and process new telemetry parameters by combining multiple actual parameters in a telemetry data stream. The newly created parameters are commonly referred to as “derived parameters” and are often required for analysis in real time at relatively high speeds. Derived parameters are created through algebraic or logical combinations of multiple parameters distributed throughout the telemetry data frame. Creation and processing of derived parameters is frequently performed in telemetry system preprocessors, which are much more efficient at processing time division multiplex data streams than general purpose processors. Providing telemetry system users with a “user friendly” method for creating and installing newly derived parameter functions has been a subject of considerable discussion. Successful implementation of derived parameter processing has typically required the telemetry system user to be knowledgeable of the telemetry preprocessor architecture and to possess software programming skills. An innovative technique which requires no programming language skills is presented in this paper. Programmers or non-programmers may use the technique to easily define derived parameter calculations. Both single derived parameters and multiple derived parameters may be calculated in the preprocessor at high throughput rates.

      Nam, Yonwoo; Murphy, Lisa D.; Bendix Field Engineering Corporation (International Foundation for Telemetering, 1992-10)
      The Network Command Processing System (NCPS) developed for the National Aeronautics and Space Administration (NASA) Ground Network (GN) stations by the Bendix Field Engineering Corporation (BFEC) is a spacecraft command system utilizing a Multibus/68030 microprocessor. This system was developed and implemented at ground stations worldwide to provide a Project Operations Control Center (POCC) with command capability for support of spacecraft operations such as the LANDSAT, Tracking and Data Relay Satellite and Nimbus-7 spacecraft. The NCPS interacts with the POCC and a local operator to process configuration requests, generate modulated uplink sequences, and inform users of the ground command link status. This paper, which provides an NCPS description, consists of two sections. The first section presents the system functional description and the hardware description. The second section presents software design considerations including the implementation of a flexible and expandable operator interface, maximization of reusable software modules, and validation of BFEC designed development tools.

      Ricker, William; Kolb, John Jr; Aydin Vector Division (International Foundation for Telemetering, 1992-10)
      Due to the vast amount of data required to be collected for design/performance analysis of operational and development systems, there has evolved a real requirement for a high-speed, large capacity, data collection/record system in a small Flight/Ruggedized package. This need is realized by several user communities and factors which include the evolution of small operational vehicles (airborne, land and UAV’s), the desire of weapons manufacturers/integrators to be independent from the vehicle during vehicle integration, and a general need for a field/airborne, reliable portable data collection system for intelligence gathering, operational performance verification and on-board data processing. In the Air Defence community, the need for a ruggedized record system was highlighted after Desert Storm, in which the operational performance of the Patriot Missile was questioned and data collection was not performed to support the performance. The Aydin Vector Division in conjunction with the prime contractor, has come up with a solution to this problem which utilizes a commercially available helical scan 8mm data storage unit. This solution provides a highly reliable record system, ruggedized for airborne and field environments and a low price in comparison with the more traditional approaches currently offered. This paper will describe the design implementation of this small ruggedized, flight worthy Data collection system deemed the ATD-800. It will also discuss the performance and limitations of implementing such a system, as well as provide several applications and solutions to different operational environments to be encountered. Additionally, the paper will conclude with several product enhancements which may benefit the flight test, operational and intelligence communities in the future.

      Faulstich, Raymond J.; Naval Air Warfare Center Aircraft Division (International Foundation for Telemetering, 1992-10)
      The Common Airborne Instrumentation System (CAIS) is being developed through the Department of Defense Central Test and Evaluation Investment Program (CTEIP) to support the flight test requirements of the military services into the next decade. CAIS consists of an airborne data acquisition segment and a ground based support segment. The system is designed to accommodate both the small user and the larger, more complex full scale development programs. This paper presents a program overview of CAIS from a users view.

      Bisson, Kenneth J.; Aptec Computer Systems (International Foundation for Telemetering, 1992-10)
      There are many applications that require multiple processors performing real-time tasks and communicating with each other over a common bus or memory. Aptec has developed a real-time multiprocessing system which reduces the integration effort needed in a custom designed system. The system uses commercially available Motorola 68000 series processors each running a real-time kernel. Software has been developed to extend the capabilities of the real-time kernel. This software is called Multiprocessor Services. The software allows tasks running on different processors to communicate with each other and a global shared memory. This paper describes the features of real-time multiprocessor hardware systems, and how the multiprocessor software coordinates the processors to operate as an integrated system.

      Griffin, Alan R.; Wooten, R. Stephen; Hanscom Air Force Base; CALCULEX, Inc. (International Foundation for Telemetering, 1992-10)
      The vast amount of data telemetered from space probe experiments requires careful management and tracking from initial receipt through acquisition, archiving, and distribution. This paper presents the automated system used at the Phillips Laboratory, Geophysics Directorate, for tracking telemetry data from its receipt at the facility to its distribution on various media to the research community. Features of the system include computerized databases, automated generation of media labels, automated generation of reports, and automated archiving.

      Johnson, Gary G.; Edwards Air Force Base (International Foundation for Telemetering, 1992-10)
      Flight testing has dramatically changed from the freewheeling “right-stuff” aviation days of the 40s and 50s. The computer age was just beginning. There was essentially no access to data other than voice and radar tracking information on the ground to monitor the flights. The advent of reliable and effective ground systems for real-time safety monitoring was still in the future. Unfortunately, the lack of these systems played a contributing role in the large number of accidents which killed or injured a significant number of our nation’s pioneer test pilots. As technology evolved, more real-time access to critical safety and performance parameters became available to our flight test engineers on the ground. This technology included sophisticated aircraft instrumentation of key measurements, improved telemetry transmission and reception, and finally, enhanced real-time processing and display of the test data to the engineers. One advantage achieved through these technological advances in testing was a tremendous improvement in flight safety. Although accidents can still happen, today they are very rare thanks, in part, to the ability to accurately monitor and control a test program on the ground. The Advanced Data Acquisition and Processing Systems (ADAPS) program is specifically tailored to meet the needs of test engineers on the ground at the Air Force Flight Test Center (AFFTC) Edwards AFB, California, to monitor a flight through the use of state-of-the-art data acquisition, processing, and display technologies. This paper provides an overall perspective of the requirements for data processing which ADAPS addresses. In addition, the ADAPS design concept, architecture, and development plan are discussed. The purpose is to describe how the ADAPS development effort meets the flight test end user needs of the 1990s. The paper concludes with a section on how we can apply the ADAPS concepts and technology to help equip the multiple Department of Defense (DoD) test centers with a common test data processing capability.