• High Explosive Radio Telemetry System

      Crawford, Ted; Bracht, Roger; Johnson, Richard; Mclaughlin, Barry; Los Alamos National Laboratories; AlliedSignal Federal Manufacturing & Technologies (International Foundation for Telemetering, 1998-10)
      This paper overviews the High Explosive Radio Telemetry (HERT) system, under co-development by Los Alamos National Laboratories and AlliedSignal Federal Manufacturing & Technologies. This telemetry system is designed to measure the initial performance of an explosive package under flight environment conditions, transmitting data from up to 64 sensors. It features high speed, accurate time resolution (10 ns) and has the ability to complete transmission of data before the system is destroyed by the explosion. In order to affect the resources and performance of a flight delivery vehicle as little as possible, the system is designed such that physical size, power requirements, and antenna demands are as small as possible.
    • High Rate Digital Demodulator ASIC

      Ghuman, Parminder; Sheikh, Salman; Koubek, Steve; Hoy, Scott; Gray, Andrew; National Aeronautics and Space Administration; Lockheed Martin Space Mission Systems & Services; SGT Inc. (International Foundation for Telemetering, 1998-10)
      The architecture of the High Rate (600 Mega-bits per second) Digital Demodulator (HRDD) ASIC capable of demodulating BPSK and QPSK modulated data is presented in this paper. The advantages of all-digital processing include increased flexibility and reliability with reduced reproduction costs. Conventional serial digital processing would require high processing rates necessitating a hardware implementation other than CMOS technology such as Gallium Arsenide (GaAs) which has high cost and power requirements. It is more desirable to use CMOS technology with its lower power requirements and higher gate density. However, digital demodulation of high data rates in CMOS requires parallel algorithms to process the sampled data at a rate lower than the data rate. The parallel processing algorithms described here were developed jointly by NASA’s Goddard Space Flight Center (GSFC) and the Jet Propulsion Laboratory (JPL). The resulting all-digital receiver has the capability to demodulate BPSK, QPSK, OQPSK, and DQPSK at data rates in excess of 300 Mega-bits per second (Mbps) per channel. This paper will provide an overview of the parallel architecture and features of the HRDR ASIC. In addition, this paper will provide an overview of the implementation of the hardware architectures used to create flexibility over conventional high rate analog or hybrid receivers. This flexibility includes a wide range of data rates, modulation schemes, and operating environments. In conclusion it will be shown how this high rate digital demodulator can be used with an off-the-shelf A/D and a flexible analog front end, both of which are numerically computer controlled, to produce a very flexible, low cost high rate digital receiver.

      Law, Gene; Whiteman, Don; IFM EFFECTS ON PCM/FM TELEMETRY SYSTEMS (International Foundation for Telemetering, 1998-10)
      Incidental Frequency Modulation (IFM) products in telemetry transmitters can be a significant cause of bit errors in received Pulse Code Modulation/Frequency Modulation (PCM/FM) telemetry data. Range Commanders Council (RCC) and other documents give little or no guidance as to acceptable levels of IFM for telemetry applications. The expected higher vibration levels of future high velocity missile systems means that IFM levels are likely to be higher than previously encountered. This paper presents measured data on Bit Error Rate (BER) versus IFM levels at given Signal to Noise Ratios (SNR’s) for PCM/FM telemetry systems. The information presented can be utilized with BER versus SNR plots in the Telemetry Applications Handbook, RCC Document 119, to determine the additional link margin required to minimize IFM effects on telemetry data quality.

      Skelley, Daniel S.; Jones, Sidney R., Jr.; Naval Air Warfare Center Aircraft Division (International Foundation for Telemetering, 1998-10)
      The purpose of this paper is to present a broad view of the impact of network architectures on future data acquisition systems. The major advantages and challenges associated with the use of network architectures are rooted in the packetized structure of the data. Many of the issues raised are subtle and complex. It is not the intent of this paper to give these issues the thorough academic and technical analysis they deserve. It is the hope of the authors this paper will generate awareness and discussion on these issues.

      Dongkai, Yang; Qishan, Zhan; Lung, Cheng Lee; Beijing University of Aeronautics and Astronautics; City University of Hong Kong (International Foundation for Telemetering, 1998-10)
      An Improved AMI (Alternate Mark Inverse) Code used in telemetry system is proposed, its implementation and properties analysis are reported, including error performance analysis, power spectrum analysis, the relationship between acqusition probability of the first frame marker and error threshold and length of frame marker, etc. This type of code has the approximately identical power spectrum performance as the AMI Code. In addition, there have no long continuous zeroes in the data stream, which will cause phase-locked loop to fail. Using the Improved AMI Code, the equal probability of 0 and 1 is changed, which will increase acqusition probability of the first frame marker. Detailed description about how to create the Improved AMI Code is also discussed in this paper.

      Abbott, Laird; 49th Test Squadron (Air Combat Command) (International Foundation for Telemetering, 1998-10)
      Airborne instrumentation used during flight tests is being installed and maintained in a unique way by operational bomber testers from the Air Force’s 53d Wing. The ability of the flight test community to test on operational aircraft has always been somewhat curtailed by the need for advanced forms of instrumentation. Operational fighter flight test squadrons have aircraft assigned to them, which they modify on as needed basis, much the same as developmental testers. However, bomber operational test units must use operational aircraft to accomplish their mission as there are no bombers in the Air Force’s Air Combat Command (ACC) specifically set aside for operational tests. During test missions, these units borrow aircraft from operational bomb wings, and then return them to service with the bomb wing after testing is complete. Yet, the requirement for instrumentation on these test missions is not much different than that of developmental testers. The weapon system engineer’s typically require Mil-Std-1553, video, telemetry, and Global Positioning System (GPS) Time-Space-Position-Information airborne receiver recordings. In addition, this data must be synchronized with an IRIG-B time code source, and recorded with the same precision as the data gathered during development test and evaluation (DT&E). As a result, several techniques have been developed, and instrumentation systems designed for these operational test units to incorporate instrumentation on operational aircraft. Several factors hamper the usual modification process in place at bases such as Edwards AFB and Eglin AFB. Primary among these is the requirement to maintain the aircraft in an operational configuration, and still meet all of the modification design safety criteria placed on the design team by the aircraft’s single manager. Secondary to the list of restrictions is modification time. Aircraft resources are stretched quite thin when one considers all of the bomb wing’s operational commitments. When they must release an aircraft for test missions, the testers must insure that schedule impacts are minimal. Therefore, these systems must install and de-install within one to two days and be completely portable. Placing holes in existing structures or adding new permanent structure is unacceptable. In addition, these aircraft must be capable of returning to combat ready status at any time. This paper centers on the B-52 bomber, and the active aircraft temporary modifications under control of the 49th Test Squadron (49 TESTS) at Barksdale AFB in Louisiana. The B-52 presents unique design challenges all its own, in addition to the general restrictions already mentioned. This paper will present the options that the 49 TESTS has successfully used to overcome the aforementioned restrictions, and provide an appropriate level of specialized instrumentation for its data collection requirements.

      Wells, Lawrence L.; Montgomery, Robert S.; Interstate Electronics Corporation (International Foundation for Telemetering, 1998-10)
      This paper describes a highly integrated and low cost GPS Translator/Telemetry system for use on missile platforms – the Digital GPS Translator (DGT), a component part of the Translated GPS Range System (TGRS). The DGT provides translated GPS tracking capability combined with transmission of telemetry at rates of up to 10 Mbps with optional encoding and/or encryption. This integrated approach to GPS tracking and telemetry results in a significant reduction in hardware size and cost compared to a segregated approach. The TGRS includes a ground-processing unit that provides real time processing of both the GPS and telemetry portions of the DGT transmission.
    • International Telemetering Conference Proceedings, Volume 34 (1998)

      International Foundation for Telemetering, 1998-10
    • ISO 9001 Registration for the Electronic Hardware Fabrication Process at the Jet Propulsion Laboratory

      Bonner, J. K. “Kirk”; de Silveira, Carl; California Institute of Technology (International Foundation for Telemetering, 1998-10)
      More and more companies and organizations are recognizing the benefits to be gained by achieving ISO 9000 registration. An effort is underway at JPL to become ISO 9001 registered. To facilitate this activity, the entire laboratory has been divided into processes, each one having a designated process owner. This paper concentrates more specifically on one of these processes, namely, the Packaging and Fabrication of Electronic Hardware (PAFEH), and the effort being undertaken to ensure that this process will successfully pass registration. A comprehensive approach is being utilized by the Electronic Packaging and Fabrication Section to bring this about.

      Shigemoto, Fred; Wei, Mei; Somes, Austin; Ng, Sunny; NASA; Sterling Software (International Foundation for Telemetering, 1998-10)
      FAA is currently evaluating DGPS based CAT III Landing Systems for use as the next generation commercial aviation landing system standard. Any technique to validate such a DGPS based system must have at least equivalent accuracy. A laser position tracking system coupled with a high performance real-time computational capability was developed providing real-time analysis of performance. This real-time performance measurement system was key in enabling the quick completion of a large number of test approach and landings needed to achieve statistically accurate results.

      Barton, Randal L.; New Mexico State University (International Foundation for Telemetering, 1998-10)
      The Near Earth Asteroid Prospector (NEAP) has a scheduled launch date between mid- 1999 and mid-2000, and will encounter a yet to be determined near Earth asteroid (1.1 - 2.2 AU distance from Earth) some ten months later [2]. The purpose of this mission is not only to collect valuable scientific and geological data, but to also determine the value of the asteroid’s materials for possible mining and exploitation [2], [3]. The purpose of this paper is to detail frequency allocation issues and to determine possible return (space to Earth) data rates associated with deep space communications with the NEAP spacecraft.

      Franco, R. J.; Platzbecker, M. R.; Sandia National Laboratories (International Foundation for Telemetering, 1998-10)
      The Telemetry Technology Development Department at Sandia National Laboratories actively develops and tests acceleration recorders for penetrating weapons. This new acceleration recorder (MinPen) utilizes a microprocessor-based architecture for operational flexibility while maintaining electronics and packaging techniques developed over years of penetrator testing. MinPen has been demonstrated to function in shock environments up to 20,000 Gs. The MinPen instrumentation development has resulted in a rugged, versatile, miniature acceleration recorder and is a valuable tool for penetrator testing in a wide range of applications.

      Leung, Joseph; Aoyagi, Michio; Billings, Donald; Hoy, Herbert; Lin, Mei; Shigemoto, Fred; NASA (International Foundation for Telemetering, 1998-10)
      As renewal interest in building vehicles based on hypersonic technologies begin to emerge again, test ranges anticipating in supporting flight research of these vehicles will face a set of engineering problems. Most fundamentals of these will be to track and gather error free telemetry from the vehicles in flight. The first series of vehicles will likely be reduced-scale models that restrict the locations and geometric shapes of the telemetry antennas. High kinetic heating will further limit antenna design and construction. Consequently, antennas radiation patterns will be sub-optimal, showing lower gains and detrimental nulls. A mobile system designed to address the technical issues above will be described. The use of antenna arrays, spatial diversity and a hybrid tracking system using optical and electronic techniques to obtain error free telemetry in the present of multipath will be presented. System tests results will also be presented.

      Glim, Carl; Universal Space Network, Inc. (International Foundation for Telemetering, 1998-10)
      The recent proliferation of Low Earth Orbiting (LEO) science, earth resources, and global communication satellites requires a significant number of ground stations for support. A network of satellite tracking ground stations with the ability to support multiple users and communicate with multiple satellites requires a robust scheduling and conflict resolution system. This paper describes an automated scheduling implementation for managing such a commercial, multi-user, multiple satellite, ground station network.
    • A Narrowband Model For Aeronautical Telemetry Channels

      Rice, Michael; Welling, Kenneth; Brigham Young University (International Foundation for Telemetering, 1998-10)
      This paper presents a narrowband channel model appropriate for modeling multipath interference in aeronautical telemetry applications. This model uses a simplified version of Bello’s aeronautical fading channel model [1] with the following three parameters: the specular to direct power ratio T, the direct to diffuse power ratio K and the relative Doppler shift of the specular component. Data taken from Patuxent River NAWC, Edwards AFB and White Sands Missile Range demonstrate that the model is a reasonably accurate statistical representation of the envelope (and power) fluctuations observed in the data. The model works well for those cases where a dominate line-of-sight signal component exists, as well as for those cases where the power in the specular reflections is on the order of the power in the line-of-sight component.

      Monica, G. Della; Tonello, E.; ALCATEL (International Foundation for Telemetering, 1998-10)
      Presentation of Alcatel Espace last studies and developments regarding TT&C receiver Products for satellite. This document lays on 3 parts: · a technical point of view showing digital demodulation principles used (base band recovery, analytical head, PM or FM demodulation) and their related offered possibilities(digital controlling loop, lock status detection, jammer detection,....) · a technology/design description · a synthesis showing performance and results

      Thames, Fred; Avalon Electronics Ltd (International Foundation for Telemetering, 1998-10)
      As the performance of inexpensive commercial off-the-shelf (COTS) data storage devices continues to increase, the temptation to use them as the basis for data capture products for military and industrial applications becomes ever more compelling. For example, the Digital Linear Tape (DLT) format now offers a 270 Gigabits per cassette capacity at a sustained transfer rate of 40 Mbits/s – performance which would have cost tens or even hundreds of thousands of dollars per system just a few years ago. But to transplant such a device from its benign office habitat into a data capture product which will function reliably and consistently in a wide range of field and platform environments is an engineering task fully as difficult and complex as designing an environmentally robust recorder from scratch. This paper discusses the problems which typically have to be overcome; environmental protection, reliability, data integrity, power supplies, software issues, control and data interfacing, etc., citing practical examples of analog and digital DLT-based data recorders which are now entering service for telemetry, intelligence gathering, anti-submarine warfare and related applications

      Jensen, Peter; Thacker, Christopher; Merlin Engineering Works (International Foundation for Telemetering, 1998-10)
      The Test & Evaluation community is starting to migrate toward solid state recording. This paper outlines some of the important areas that are new to solid state recording as well as examining some of the issues involved in moving to a direct recording methodology. Some of the parameters used to choose a solid state memory architecture are included. A matrix to compare various methods of data recording, such as solid state and magnetic tape recording, will be discussed. These various methods will be evaluated using the following parameters: Ruggedness (Shock, Vibration, Temperature), Capacity, and Reliability (Error Correction). A short discussion of data formats with an emphasis on efficiency and usability is included.

      Sullivan, Arthur; Christodoulou, Christos; Chandler, Charles W. (International Foundation for Telemetering, 1998-10)
      The next generation Digital Beamforming Array (DBFA) requires techniques beyond the existing adaptive processing and optimization approaches. By utilizing neural network processing and genetic algorithms that mimic complicated natural processes, such as the brain and natural selection, new and superior Antenna Arrays can be designed. The use of Neural Networks and Genetic Algorithms combined with the existing techniques for DBFAs can yield the ultimate in “real-time,” “smart” antenna performance. Cost is significantly reduced by; allowing large manufacturing tolerances, the use of inexpensive components, and correcting by neural network techniques. This paper describes the technology and proposes a practical application of the technique to design a DBFA to track and transmit/receive telemetry from a shipboard vertically launched medium range missile.

      Walter, Patrick L.; Texas Christian University; Endevco (International Foundation for Telemetering, 1998-10)
      Acquiring shock and vibration data from flight vehicles through rf telemetry links has numerous associated challenges. Yet, these measurements are important to establish environmental specifications to provide a basis for system or component design and testing. The principal limitation in acquiring these measurements is the frequency bandwidth available for data transmission. This limited bandwidth is often responsible for invalid data being accepted as valid. This work provides a brief review of time and frequency division multiplexing to identify the potential error contributors to shock and vibration measurements. Its focus is on the design of acceleration measurement systems to eliminate these errors and optimize individual measurement channel performance.