Now showing items 21-40 of 95

    • Bridging The Gap Between Telemetry and the PC

      Nelson, Wade; Shurtleff, Diana; Loral Instrumentation (International Foundation for Telemetering, 1988-10)
      The explosive use and extensive development of software and hardware for the IBM PC and PC Clones over the past few years has positioned the PC as one of many viable alternatives to system designers configuring systems for both data acquisition and data analysis. Hardware abounds for capturing signals to be digitized and analyzed by software developed for the PC. Communication software has improved to where system developers can easily link instrumentation devices together to form integrated test environments for analyzing and displaying data. Telemetry systems, notable those developed for lab calibration and ground station environments, are one of many applications which can profit from the rapid development of data acquisition techniques for the PC. Recently developed for the ADS100A telemetry processor is a data acquisition module which allows the system to be linked into the PC world. The MUX-I/O module was designed to allow the PC access to telemetry data acquired through the ADS 100A, as well as provide a method by which data can be input into the telemetry environment from a host PC or equivalent RS-232 or GPIB interface. Signals captured and digitized by the ADS100A can be passed on to the PC for further processing and/or report generation. Providing interfaces of this form to the PC greatly enhances the functionality and scope of the abilities already provided by the ADS100A as one of the major front-end processors used in telemetry processing today. The MUX-I/O module helps "bridge the gap" between telemetry and the PC in an ever increasing demand for improving the quantity and quality of processing power required by today's telemetry environment. This paper focuses on two distinct topics, how to transfer data to and from the PC and what off-the-shelf software is available to provide communication links and analysis of incoming data. Major areas of discussion will include software protocols, pre vs post processing, static vs dynamic processing environments, and discussion of the major data analysis and acquisition packages available for the PC today, such as DaDisp and Lotus Measure, which aid the system designer in analyzing and displaying telemetry data. Novel applications of the telemetry to PC link will be discussed.
    • Software Control of a High Speed, Modular Signal Conditioner and PCM Encoder System

      Trover, William F.; Teledyne Controls (International Foundation for Telemetering, 1988-10)
      The increasing channel capacity and complexity of flight test data acquisition systems have made the problems of physical distribution of the system throughout the test aircraft and determining the system configuration a very time consuming and costly portion of the flight test process. These problems are complicated because the new aircraft, irrespective of size, have more complex systems and less space is available to install the classical data acquisition and recording system. The solution to the installation problem is to have a highly modular system that can be configured as either a distributed system with remote multiplexing and a PCM Central Controller, or with the same multiplexed hardware as a stand-alone or master/slave system where the functional power and complexity afforded by the PCM Central Controller are not required. The solution to the configuration control problem is to have a 'hands-off' data acquisition system with all variables of the signal conditioning and PCM encoding functions under software control. In one concept, this includes functions such as instrumentation amplifier gains and offsets, presample filter knee selection, a common gain programmable amplifier with programmable offsets, and randomly addressable multiplexers with a PCM Central Controller that can store multiple data cycle maps. With all of the variable functions of the system under software control, system configuration can be determined automatically during pre- and post-flight test from a portable ground test set that produces a hardcopy printout of the system configuration. This system concept is being augmented by increasing sampling rate capability up to 500k sps for processing vibration/acoustic data. Fiber optical communications are available between the PCM Central Controller and the remote signal conditioners and multiplexers to provide immunity from extremely high common mode plateaus between subsystem elements located in different parts of a composite materials airframe. This next generation data system is being developed for general purpose flight and ground test applications.
    • Analysis On the Optimum Group Synchronization Code of TIROS Satellite

      Qiu-Cheng, Xie; Jie, Cao; Nanjing Aeronautical Institute (International Foundation for Telemetering, 1988-10)
      In this paper, the group synchronization code (length n = 60 bit) of the TIROS Satellite was analysed. It seems to us the code isn't optimization. A series of optimum group sync codes (n = 60) have been searched out with error tolerance E = 1, 2, 3, 4, 5, 6 and 10, 12. Their error sync probabilities are less than the error sync probability of the TIROS code (from two times to two order of magnitudes about). These optimum or qansi-optimum codes will be presented for application in the second generation of the Meteorological Satellites of China.
    • A Flexible Telemetry Processor for Spacecraft Testing

      Leng, Christopher; Peet, Arthur; Jet Propulsion Laboratory/California Institute of Technology; Martin Marietta Astronautics Group (International Foundation for Telemetering, 1988-10)
      In the past, telemetry data systems in support of JPL flight projects -- such as Voyager and Galileo -- were designed specifically for each mission. Third-generation computers and minicomputers were combined into a distributed system, and many man-hours of software development were invested to meet each project's unique processing requirements. These systems were used to support the Spacecraft testing on the ground and -- later -- for mission operations after launch. The Magellan System Test Data Processing Subsystem (STDPS) marks a departure from these past designs. For the first time, a re-usable telemetry-processing subsystem has been designed that is flexible enough to meet the spacecraft-testing requirements of the present project -- and can be easily changed for future projects as well. These changes are all accomplished through a user-friendly, menu-oriented interface. Extensive software re-programming is no longer required. The Magellan spacecraft is being constructed for JPL by Martin Marietta Astronautics Group, Denver, Colorado. The STDPS is currently in Denver, supporting the spacecraft testing.
    • GPS: The Versatile Tool for Range Instrumentation

      Hoefener, Carl; Richardson, William; Interstate Electronics Corporation (International Foundation for Telemetering, 1988-10)
      The Global Positioning System (GPS) has made significant contributions in range instrumentation. It was the prime tracking method for both realtime range safety and metric tracking for the Trident II. Because of its many advantages, GPS will become the primary source of time, space, and position information (TSPI) on the ranges. Many activities requiring precision TSPI have already committed to GPS and others are planning on the application of GPS in the future for use on the ranges. GPS is also an extremely accurate time source, with timing accuracies of 10 nanoseconds obtainable worldwide. The range interoperability problem is solvable through the use of GPS as the TSPI source. There is little doubt that GPS will become the standard TSPI source for all test and training ranges.
    • Digital Microwave System Mobile, All-Terrain System for Telemetry or Communications

      Strom, Robert L.; Emmenegger, J. M. (Hans); Boeing Aerospace Company; Broadcast Microwave Services, Inc. (International Foundation for Telemetering, 1988-10)
      Portable, mobile tactical microwave telemetry and/or communications systems have always been plagued with three major problems: antenna height for first fresnel zone clearance over the terrain between the two ends of the link, atmospheric multipath fading and multipath reflections from buildings, bodies of water, certain terrain features, etc. This paper describes a digital microwave system with a modular capability to add additional digital channels, analog channels or voice channels as required. A modular Baseband Processor is used, which provides multiplexing capability and modulation of high speed digital data at a bandwidth of one bit per Hz using the Duobinary Technique which also provides error detection capability without the need for adding extra bits to the stream.
    • MMTS: Multi-Vehicle Metric & Telemetry System

      Aspnes, Richard K.; Yuma, Russell J.; Control Data Corporation (International Foundation for Telemetering, 1988-10)
      The Multi-Vehicle Metric & Telemetry System (MMTS) is a complete range system which performs real-time tracking, command destruct, and telemetry processing functions for support of range safety and the test and evaluation of airborne vehicles. As currently configured, the MMTS consists of five hardware and software subsystems with the capability to receive, process, and display tracking data from up to ten range sensors and telemetry data from two instrumented vehicles. During a range operation, the MMTS is employed to collect, process, and display tracking and telemetry data. The instrumentation sites designated for operational support acquire tracking and telemetered data and transmit these data to the MMTS. The raw data is then identified, formatted, time tagged, recorded, processed, and routed for display to mission control and telemetry display areas. Additionally, processed tracking data is transmitted back to instrumentation sites as an aid to acquire or maintain vehicle track. The mission control area consists of a control and status console, high resolution color graphics stations, and large screen displays. As the mission controller observes mission progress on the graphics stations operational decisions can be made and invoked by activation of the appropriate console controls. Visual alarms provided my MMTS will alert mission control personnel of hazardous conditions posed by any tracked vehicle. Manual action can then be taken to activate transmission of the MMTS vehicle destruct signal. The telemetry display area consists of ten fully-functional, PC compatible computers which are switchable to either of two telemetry front end processors. Each PC can be independently set up by telemetry analysts to display data of interest. A total of thirty data pages per PC can be defined and any defined data page can be activated during a mission. A unique feature of the MMTS is that telemetry data can be combined with tracking data for use by the range safety functions.
    • The Need for Standardized Performance Characteristics for Digital Strip Chart Recorders

      Smith, Grant M.; Gaskill, Dave; Astro-Med, Inc. (International Foundation for Telemetering, 1988-10)
      Digital-based linear-array chart recorders are replacing conventional stylus recorders in telemetry data stations everywhere. They offer advantages in virtually all respects, and are becoming indispensable. But because of the completely different writing method and technology employed, it is difficult to make completely analogous performance comparisons between analog and digital chart recorders. This has led to some confusion when replacing aging stylus recorders is contemplated. Objectives: Establish a set of universal, standardized performance characteristics for digital chart recorders. Introduce appropriate terminology, allowing valid, repeatable comparison of old and new systems.
    • Static RAM Data Recorder for Flight Tests

      Stoner, D. C.; Eklund, T. F. F.; Sandia National Laboratories (International Foundation for Telemetering, 1988-10)
      A static Random Access Memory (RAM) data recorder has been developed to recover strain and acceleration data during development tests of high-speed earth penetrating vehicles. Bi-level inputs are also available for continuity measurements. An iteration of this system was modified for use on water entry evaluations.
    • Distributed, Real-Time, High-Resolution Color Graphics Display System for Telemetry

      Querido, Robert; Friedman, Paul J.; Loral Instrumentation (International Foundation for Telemetering, 1988-10)
      Dramatic increases in telemetry data rates and sources require test engineers to view and digest real-time data in order to make cogent decisions about whether to continue or modify flight tests. Traditional telemetry systems offer limited insight through a myriad of strip charts and alphanumeric displays. Attempts to improve this human interface employed expensive central superminicomputers and display systems. Although these methods have been successful, development and procurement costs and delays have limited their deployment. Recent advances in low-cost standard display, processing, and network technology have led to the development of the System 500. The System 500 employs a distributed architecture. Independent, relatively low cost, high-resolution color graphics workstations connect to the data acquisition and processing subsystems via Ethernet.* Each station is independent, requesting and then receiving only data for display. The combined ability to physically display and update only a few hundred parameters, each at relatively few samples per second makes Ethernet and standard upper layer protocols ideal for this application. The state-of-the-art human interface lets users select or mix a variety of methods to create and modify display contents, including: choosing from a list using arrow keys or a mouse, moving a scroll bar to pan through parameter files, or entering commands via keyboard where response anticipation reduces keystrokes to those uniquely defining a choice. A repertoire of graphic window displays is available to present real-time and static data concisely in analog and alphanumeric formats. Window size, location, and color have been chosen to focus attention rather than beautify. Standard windows and accent colors direct user attention to specific areas without cluttering and distracting.
    • A Programming Parallel Real-Time Process Data Flow Telemetry System

      Da-qing, Huang; Nanjing Aeronautical Institute (International Foundation for Telemetering, 1988-10)
      In this paper, a programming parallel real-time process data flow telemetry system is presented. What we developed recently is a advanced telemetry system which can process multi-data-flow of multi-target for mulit-user at the same time. It can be used in RPV, missile and others. Its main characteristics are as follows: Input radio frequency is S wave band (multi-dot frequencies). In telemetry front-end, the chip microprocessor is used to make demodulation and decode. Telemetry preprocessor consists of parallel distributed chip microprocessor mould plates (bus link). There are menu shope man-computer dialogue, figure display, intelligence display and intelligence self-diagnosis in this system. Now, we have developed data compress mould plate, floating-point arithmetic mould plate, derive calculation mould plate and signal process mould plate etc. The main computer is VAX-II.
    • Practical Decom List Switching

      Devlin, Steve; Aydin Monitor Systems (International Foundation for Telemetering, 1988-10)
      With more complex vehicle designs, the frequency and number of measurements contained in telemetry data streams has dramatically increased. One way of improving the use of bandwidth is to change the sample rate, quantity, or type of measurements dynamically. A telemetry front end must be programmable to handle different formats. In a front end that decommutates and routes measurements, a decom list is a control program, which defines the location, size, orientation, and identity of the measurements. To deal with dynamic format changes, a telemetry front end must be able to switch between decom lists. A practical approach to decom list switching must address the needs of error avoidance, packet switching, and the location of switching keys in any portion of the format. Switching between formats should not be restricted to a preprogrammed sequence, but should allow multiple destinations from a particular decom list. A practical and flexible implementation of decom list switching is detailed along with an explanation of how this implementation solves a variety of decommutation problems.
    • High Performance, Real-Time, Parallel Processing Telemetry System

      Powell, Richard L.; Williamson, Gale L.; Razavian, Farhand; Friedman, Paul J.; Loral Instrumentation (International Foundation for Telemetering, 1988-10)
      Flight test and signal and image processing systems have shown an increasingly voracious appetite for computer resources. Previous solutions employed special-purpose, bit-sliced technology to supplant costly general purpose computers. Although the hardware is less expensive and the throughput greater, the expense to develop or modify applications is very high. Recent parallel processor technology has increased capabilities, but the high applications development cost remains. Input/output (I/O) such as intermediate mass storage and display has been limited to transfer to general purpose or attached I/O computers. The PRO 550 Processing and Storage Subsystem of the System 500 was developed to provide linearly expandable, programmable real-time processing and an interface to distributed data acquisition subsystems. Each data acquisition subsystem can acquire data from multiple telemetry and other real-time sources. Processing resources are provided by one or more 8 MIPS (20 MFLOPS peak) processor modules, which utilize an array of predefined algorithms, algorithms specified by algebraic notation, or developed via high level languages (C and Fortran). Setup and program development occur on an external, general purpose color graphics workstation that is connected to the subsystem via an Ethernet network for command, control, and resultant data display. High-performance peripherals and processors communicate with each other via a 16-MHz broadcast bus, the MUXbus II, where any or all devices can acquire data elements called tokens. A token is a single MUXbus II word of 32 bits of data and a 16-bit tag to identify the word uniquely to the acquiring modules. The output of each device to the bus can be one or more tokens, but each device captures the bus to insert a single token. This ensures all devices receive equal priority and the MUXbus II is maximally utilized. This multiple instruction, multiple data (MIMD) architecture automatically schedules and routes data to processors or to I/O modules without control processor overhead. Traditional peripherals and administrative functions utilize the second subsystem bus, which is a traditional VMEbus. It controls the high performance devices while permitting the utilization of standard off-the-shelf controllers (e.g., magnetic tape, Ethernet, and bus controllers) for less demanding I/O tasks. A dedicated Bridge Module is the gateway for moving data between bus domains.
    • Decommutation of Mil-Std 1553B Data from EA6B or IRIG Telemetry Formats

      Devlin, Steve; Aydin Monitor Systems (International Foundation for Telemetering, 1988-10)
      With the acceptance of Mil-Std-1553B by vehicle and weapons industries a wealth of new information is available for vehicle testing. In the past, selected data was extracted and included in a standard PCM telemetry stream. But only the selected data was made available. In EA6B and in the proposed IRIG Standard, multiple Mil-Std-1553B data busses are combined with identifying control bits in a single PCM telemetry stream. All of the information traveling each bus is available to the ground station. These formats share a number of features. One is that for each Bus the Mil-Std-1553B word appears in the same order in the telemetry stream. Another is that individual data words do not depend on their position in the telemetry stream for identification, but they do depend on the control information associated with the current message to give meaning to the data words. An efficient approach is outlined for identifying, selecting and routing individual measurements, messages, and/or all Mil-Std-1553B bus information to processes and I/O devices in a data flow environment.
    • The Application of a Distributed Computing Architecture to a Large Telemetry Ground Station

      Buell, Robert K.; Fairchild Weston Systems Inc. (International Foundation for Telemetering, 1988-10)
      The evolution of telemetry ground station systems over the past twenty years has tracked the evolution of the mini-computer industry during that same time period. As the various mini-computer vendors introduced systems offering ever increasing compute power, and ever increasing capabilities to support multiple simultaneous users, the high end of the telemetry ground station systems offered by the industry evolved from single stream, single user, raw data systems to multi-user, multiple stream systems supporting real-time data processing and display functions from a single CPU or, in some cases, a closely coupled set of CPUs. In more recent years we have seen the maturation of networking and clustering concepts within the digital computer industry to a point where such systems coupled with current workstation technology, now permit the development of large telemetry ground station systems which accommodate large numbers of simultaneous users, each with his or her own dedicated computing resources. This paper discusses, at a hardware block diagram and software functional level, the architecture of such a distributed system.
    • Telemetry Data Processing: A Modular, Expandable Approach

      Devlin, Steve; Aydin Monitor Systems (International Foundation for Telemetering, 1988-10)
      The growing complexity of missle, aircraft, and space vehicle systems, along with the advent of fly-by-wire and ultra-high performance unstable airframe technology has created an exploding demand for real time processing power. Recent VLSI developements have allowed addressing these needs in the design of a multi-processor subsystem supplying 10 MIPS and 5 MFLOPS per processor. To provide up to 70 MIPS a Digital Signal Processing subsystem may be configured with up to 7 Processors. Multiple subsystems may be employed in a data processing system to give the user virtually unlimited processing power. Within the DSP module, communication between cards is over a high speed, arbitrated Private Data bus. This prevents the saturation of the system bus with intermediate results, and allows a multiple processor configuration to make full use of each processor. Design goals for a single processor included executing number system conversions, data compression algorithms and 1st order polynomials in under 2 microseconds, and 5th order polynomials in under 4 microseconds. The processor design meets or exceeds all of these goals. Recently upgraded VLSI is available, and makes possible a performance enhancement to 11 MIPS and 9 MFLOPS per processor with reduced power consumption. Design tradeoffs and example applications are presented.
    • Evolutionary Factors in the Development of a Realtime Multiprocessor System

      Trover, William F.; Teledyne Controls (International Foundation for Telemetering, 1988-10)
      Architectural decisions made three years ago in the design of a high speed preprocessor system for realtime data processing at sustained rates of 200k to 300k parameters per second were driven by the need to provide expansion flexibility and to permit the user to program application algorithms through the use of a high level language. The original design concept was a two bus architecture which would accept and merge data from up to 8 data sources with the required number of parallel computers driven by the realtime processing needs - not the 1.5M wps aggregate throughput capability. Other configuration variables were to enable the use of an optional raw data circular (wrap around) file for intermaneuver or anomaly analysis, the number of analog and discrete outputs for strip chart and visual displays, and the ability to support a wide range of processed data throughputs to one or more host computers. As a result of future defined requirements, the expansion capability ultimately grew to allow up to 30 data sources, 256 analog outputs, and 196 discrete outputs. A concurrent study of the engine and airborne test community showed that in many applications over 50% of the processing was restricted to repetitive computations such as FFTs and first order EU conversions. Although bit slice processors were much faster than general purpose Application Processors (APs), nobody in the user community said they wanted to write microcode to install their application programs. As the first customer's requirements could be easily handled by adding a few APs, the initial system design concentrated only on general purpose processors with provisions being made for the future addition of special purpose digital signal processors to co-reside with the general purpose APs. At the some time, much of the rotary wing test community's data processing was highly floating point intensive so the AP processor was designed with an independent floating point processor using the fastest possible device technology. The original two bus architecture using industry standard Versa and VME buses evolved as the design matured to a six bus architecture capable of supporting up to 60 parallel processors. The use of industry standard buses has permitted successful development of configurations using a wide range of third party processors and peripherals from a variety of sources. Larger system configurations are implemented by a multi-chassis structure with functions arranged so that no realtime bus is unterminated or physically longer than 19 inches. The simultaneous software development supporting these changes and encompassing 25 man-years of work is beyond the scope of this paper and will be covered in a separate publication.
    • Research and Recommendation of Optimum Group Synchronization Codes for N = 7 -- 32

      Zhongkui, Lei; Qiucheng, Xie; Jie, Cao; Nanjing Aeronautical Institute (International Foundation for Telemetering, 1988-10)
      In this paper, based on a series of research achievements [2,3,4,5,6], are examined the "The Optimum Frame Synchronization Codes" provided by J. L. Maury Jr. and F. J. Styles for IRIG Telemetry Standards USA, and furthermore, recommended a set of Optimum Group Synchronization Codes for China Telemetry Standards.
    • Characteristics and Application of "Smart" Shaft Encoders

      Breslow, Donald H.; Litton Industries (International Foundation for Telemetering, 1988-10)
      A family of absolute optical shaft encoders has been configured which is based upon an electro-optical multiplexing architecture. When interfaced to a microprocessor, the resulting "smart" encoder can perform several allied data processing functions and can replace many types of electro-mechanical components. Encoder architecture, interfacing, and several allied signal processing examples are discussed.
    • VLSI High Speed Packet Processor

      Grebowsky, Gerald J.; Dominy, Carol T.; NASA Goddard Space Flight Center (International Foundation for Telemetering, 1988-10)
      The Goddard Space Flight Center Mission Operations and Data Systems Directorate has developed a Packet Processor card utilizing semi-custom very large scale integration (VLSI) devices, microprocessors, and programmable gate arrays to support the implementation of multi-channel telemetry data capture systems. This card will receive synchronized error corrected telemetry transfer frames and output annotated application packets derived from this data. An adaptable format capability is provided by the programmability of three microprocessors while the throughput capability of the Packet Processor is achieved by a data pipeline consisting of two separate RAM systems controlled by specially designed semi-custom VLSI logic.