• Sensing of Irregularities on Fast Moving Surfaces by Microwaves and Millimeterwaves

      Ishii, T. Koryu; Marquette University (International Foundation for Telemetering, 1988-10)
      Fine cracks and irregularities on a fast moving conducting surface were detected by the use of microwave and millimeter wave radio responder techniques. The interrogation angle was restricted to an oblique incidence angle less than ±0.5 degree from the surface. The fast moving conducting surface was surrounded by both fast moving and stationary reflective conducting structures. Experimental methods and results from a fine crack 0.1 mm wide, 0.9 mm deep, and 25 mm long on a conducting surface travelling with a speed of 20.23 m/s and measured at 10.525 GH(z) and 73 GH(z) are presented. The reflection-type microwave radio responder consisted of a 10.525 GH(z) 50 mW Gunn diode cw transmitter, a circulator, and a horn antenna used as the interrogator. The receiver in the same responder consisted of the same horn antenna, the circulator and detector diode. The detector diode output was observed with a Norland 3106R digital memory oscilloscope. A reflex kylstron VA 250 was used as the transmitter signal source for the millimeter wave responder. There was a distinct difference between the responder output patterns with uncracked and cracked surfaces. It is therefore possible to use this type of responder for hair-line crack detection of fast moving conducting surfaces. It was also found that this type of radio responder can detect the surface irregularity even before the hairline crack actually occurs.
    • Several Problems in Chinese Development of Telemetry Technology

      Chang-jie, Shi; Shang-ren, Li; Ministry of Aeronautics and Astronautics; Beijing Research Institute of Telemetry (International Foundation for Telemetering, 1988-10)
      1. What is the reason for the telemetry ground station using computer technology widely and deeply? 2. How to solve the problem of measuring fast varing signal? 3. Bit rate of telemetry ground station.
    • A New Multi-Mission Data System for Space Flight Support Through the 1990's

      Gainsborough, A. J.; California Institute of Technology (International Foundation for Telemetering, 1988-10)
      Individual data systems for flight projects at JPL are in the process of being replaced by the single new Space Flight Operations Center (SFOC) that is designed to support multiple missions. The design provides a baseline system that supplies a common set of functions needed by every mission. Low cost adaptations of the baseline with any needed missionspecific additions are made for each mission. The SFOC is being developed in phases. The current phase provides baseline functions for downlink spacecraft telemetry processing with the necessary adaptations and additions for the downlink launch support in April 1989 of the Magellan mission to Venus. The SFOC will be completed in 1991, at which time the planned support includes both downlink and uplink processing for a projected six mission set.
    • A High Data Rate Airborne Rotary Recorder with Long Record Time

      Leung, Victor; DATATAPE Incorporated (International Foundation for Telemetering, 1988-10)
      Application of instrumentation recorders for data acquisition in hostile environments has for years been accomplished by means of longitudinal recorders specially designed for that application. DATATAPE Incorporated has been the leader in providing such recorders beginning with its MARS series. Two recent trends have impacted the applicability of these machines: the need for record times longer than can be provided by the longitudinal machines and the trend in the instrumentation industry to utilize digital recording techniques.
    • Video Compression Standardization Issues

      Stephens, Charles R.; Premmco (International Foundation for Telemetering, 1988-10)
      This paper discusses the development of a standard for compressed digital video. The benefits and applications of compressed digital video are reviewed, and some examples of compression techniques are presented. A hardware implementation of a differential pulse code modulation approach is examined.
    • 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.
    • Applications of Measurement Instrumentation for Advanced Launch Vehicles of the 90's Using MicroDACS Technology

      Martin, Robert D.; SCI Technology Inc. (International Foundation for Telemetering, 1988-10)
      Using MicroDACS* SMT ASIC technology, an instrumentation and control system is designed to meet the low cost, fault tolerant, data handling requirements for advanced launch vehicles of the 901's. Advanced launch vehicles will require low cost autonomous, and reliable measurement circuits. This paper describes many measurements and signal conditioning applications for various types of analog transducers needed to insure missile health and safety on boosters of the future.
    • Application of Digital Video in Modern Telemetry Systems

      Druif, David; LORAL/CONIC (International Foundation for Telemetering, 1988-10)
      This paper addresses the system issues of applying digital video to modern telemetry systems and problems. Comparison of typical link budgets, block diagrams, as well as improvements and limitations for both analog and digital video are included. Encryption issues are covered from a generic unclassified point of view.
    • The Searching Method of Optimum Frame Synchronization Codes Based on the Synthetic Optimum Criterior

      Jie, Cao; Qiu-Cheng, Xie; Nanjing Aeronautical Institute (International Foundation for Telemetering, 1988-10)
      This paper gives a new searching criterior of optimum or suboptimum frame sync codes that escapes from unnecessary calculation and presents a searching method. It has a great improvement on existing methods (exhaustion technique, and so on) and the computing time is decreased by 1~2 order of magnitudes. Finally, the optimum frame sync codes with the length n from 7 to 32 are given.
    • Problems and Methodology of High Data Rate Telemetry

      Baghdady, Elie J.; EJB Research Associates (International Foundation for Telemetering, 1988-10)
      The ultimate limitations on data rate are set by factors categorized in this paper into transmission medium problems, equipment problems and signal characteristics in the generalized spectral dimensions of time, frequency and open space. The limiting factors and corresponding relieving approaches are briefly brought out in this essentially topical summary paper. This paper is primarily a topical guide for a much more detailed multiple-hour tutorial lecture.
    • 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.
    • Spaceborne Recording Systems for the Space Station Era

      Muench, Jerry; Odetics, Inc. (International Foundation for Telemetering, 1988-10)
      A detailed review of spaceborne magnetic tape recorder technology from the late 1970s to the Space Station era is presented. Background information indicates the oft maligned space tape recorder has continued to demonstrate improving reliability since the marginal performances throughout the 1960s. Specifically, the SPOT recorder is reviewed in technical detail to show evolution through LANDSAT 6 and 7 versions, JERS-1, and finally the proposed ultimate version for Space Station/EOS. Enabling technologies include active tape tracking, magnetic recording head advances, and extensive use of ASIC devices to reduce the EEE piece part count. Suitability of the proposed Space Station/EOS recorder technologies for even more advanced future applications are discussed with data rates to 1 Gbps and storage capacities to 1 X 10¹² bits.
    • A DPCM Approach to Video Compression

      West, Jim; Moore, Willard; LORAL/CONIC (International Foundation for Telemetering, 1988-10)
      This paper presents a working Variable Length Differential Pulse Code Modulation (VDLPCM) video compression/decompression and encryption system. Included are theory of operation and performance characteristics, as well as a study of packaging problems which arise from using this hardware for severe environmental applications. No classified issues are covered.
    • RF Hybrid Linear Amplifier Using Diamond Heat Sink

      Karabudak, Nafiz; Aydin Vector Division (International Foundation for Telemetering, 1988-10)
      This paper will address the applications and methods used for a high power output RF linear small signal amplifier using diamond heat sink. Comparison and the benefits of using diamond heat spreaders will be reviewed. Agrowing number of researchers, engineers and scientists are looking into the applications of diamond's unique properties such as physical, electrical and optical.
    • 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.
    • uDACS Micropackaged Data Acquisition and Control System

      Sodini, Gregory L.; SCI Technology Inc. (International Foundation for Telemetering, 1988-10)
      The miniaturization of Aerospace Systems, has created a demand for effective, compact, lightweight, and power efficient General Purpose Stand-Alone Flight Computers, as well as Command, Data Handling and Control Systems, that maintain High Reliability, Full Redundancy, Radiation Hardness, Explosive Processing Speed, Rapid Throughput, and High Accuracy. The innovative design techniques used in the uDACS (Micropackaged Data Acquisition and Control System) offer a unique and comprehensive solution to this quandary.
    • Addition of Video to Telemetry Tracking System Upgrades Spatial Data to Radar-Quality

      Fournier, John; Sullivan, Arthur; Electro Magnetic Processes, Inc. (International Foundation for Telemetering, 1988-10)
      Traditionally telemetry trackers have not been required to provide precision space-position data. Such data, when needed, has required expensive radar or optical support. Currently, an increasing number of flight test operations have need of precision spatial data, in conjunction with telemetry data reception, in areas where no radar or optical support is available. To meet this need, EMP has carefully combined existing technologies to upgrade the angle output data accuracy of telemetry trackers to the level expected of precision radars. A TV Boresight Camera and video Tracking Error Detector combined with the EMP Model ACU-6 microprocessor-based Antenna Control Unit provide the means to automatically measure and store all of the systematic bias errors inherent in a telemetry tracking system. The resulting error model is used to provide real-time-data-correction for each error parameter. Video tracking provides correction for dynamic tracking errors in real time. Calibrations utilize boresight and stellar targets. The design goal to reduce dynamic angle data error to <10 arc seconds, RMS, appears to be reasonable.
    • Simple Digital Encoder for NTSC Composite Video

      Milles, George T.; Naval Weapons Center (International Foundation for Telemetering, 1988-10)
      The need exists to encode NTSC composite video into a serial digital bit stream for encryption prior to transmission. Further, this need exists in places where power and volume are at a premium. This paper describes a simple solution using the Continuously Variable Slope Delta Modulation technique of encoding all lines and fields in real time and is usable with clock rates from 5 to 25 MHz. The circuits presented use only a 5-volt power supply and two active devices: a comparator and either a dual flip-flop or serial shift register.
    • 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 Speed Data Acquisition Systems

      Talmadge, Richard D.; Radmand, Mansour; Wright-Patterson Air Force Base; Aydin Vector Division (International Foundation for Telemetering, 1988-10)
      Air Force systems testing today requires that more and more data be acquired to a higher degree of accuracy and in fewer flights. This necessitates a new approach to dynamic data acquisition system design. In the past data acquisition organizations used either direct or FM recording techniques of one sort or another to acquire data for post test processing. This paper will outline the direction that this organization is taking to reduce the size of the installed system as well as the time and money required to maintain the system during the testing process. The system discussed provides a capability to acquire both static (DC) data and dynamic data up to 10,000 Hertz and has a dynamic range in excess of 120 dB.