• TELEMETRY AND RADIO FREQUENCY IDENTIFICATION

      Heikkinen, Jouko; Tampere University of Technology (International Foundation for Telemetering, 1999-10)
      Comparison of short-range telemetry and radio frequency identification (RFID) systems reveals that they are based on very similar operating principles. Combining the identification and measurement functions into one transponder sensor offers added value for both RFID and telemetry systems. The presence of a memory (e.g. FRAM) in the transponder, required for ID information, can also be utilized for storing measurement results. For passive transponders low power consumption is one of the main objectives. Wireless power transfer for passive transponder sensors together with above aspects concerning a combined telemetry and identification system are discussed.
    • A VERSATILE PROGRAMMABLE FUNCTION RF ASIC FOR SPACE-BASED RF SYSTEMS

      McMahon, Michael; Rhoads, Albert; Winter, Frank; Pierson, Graham; L-3 Communications (International Foundation for Telemetering, 1999-10)
      A programmable RF ASIC is described which provides most of the RF functions within a next generation S-band transponder for space applications. The unique 18-contact LCC device can be programmed to perform a variety of RF and analog functions. This single space qualified high speed bipolar "function toolbox" is used in 39 locations throughout the transponder to provide a flexible radio architecture. The ASIC design process, internal electrical design, circuit application, space environment performance, and RF testing of the RF ASIC are described. This proprietary part provides a space-qualified solution for RF circuitry that can be applied to a variety of space application products.
    • FLIGHT TEST INSTRUMENTATION OF THE PUSH-PULL EFFECT ON A CF-18 AIRCRAFT

      Caballero, Rubén; Canadian Forces Base Cold Lake (International Foundation for Telemetering, 1999-10)
      During high performance fighter aircraft manoeuvres, a fighter pilot may be exposed to a physiological phenomenon known as the “Push-Pull Effect” (reference (ref) [1]). This effect will alter the pilot’s homeostasis whereas blood flow to the brain will be increased during low negative normal acceleration (-Gz) and suddenly decreased during positive normal acceleration (+Gz). It has been hypothesized that this effect can lessen the Gtolerance of the human body thereby making the subject more susceptible to G induced Loss of Consciousness (G-LOC) (refs [2], [3] and [4]). G-LOC is not a desirable state for a pilot in a high performance aircraft such as a CF-18. To better understand and study the Push-Pull Effect on a fighter pilot, the Aerospace Engineering Test Establishment (AETE) and the Defence and Civil Institute of Environmental Medicine (DCIEM) produced an In-Flight Research (IFR) Program sponsored by the Canadian Forces (CF). The aim of this program was to measure the physiological response of relaxed test subjects, unprotected by a G-suit, when exposed to the Push-Pull manoeuvre in flight. This IFR would validate the centrifuge data and confirm that the Push-Pull Effect can occur in flight. This paper will present the instrumentation, design, telemetry system and installation methodology utilized to perform experimental physiological research on a high performance, ejection seat equipped fighter aircraft (CF-18). Also, preliminary results on the Push-Pull Effect, obtained through this IFR Program will be presented.
    • A LAUNCH VEHICLE VIDEO TELEMETRY SYSTEM

      Meier, Robert C.; Cincinnati Electronics Corporation (International Foundation for Telemetering, 1999-10)
      Collecting and analyzing vehicle performance data is an essential part of the launch process. Performance data is used to determine mission success. Performance data also provides essential feedback to the launch vehicle design engineers. This feedback can be used to improve the overall vehicle design and thereby improve the probability of a successful launch. Various Telemetry products are used to gather and process critical information on board launch vehicles. Data is transmitted by RF links to fixed or mobile receiving stations. These Telemetry products are ruggedized for the extreme launch environments. This paper discusses the use of video telemetry as a means of providing launch vehicle performance data.
    • FLIGHT TESTING IS OUR PROFESSION – AN OVERVIEW OF TEST FLIGHT AND DEVELOPMENT CENTRE

      Schuite, Gerard; South African Air Force (International Foundation for Telemetering, 1999-10)
      The aim of this presentation is to give an overview of TFDC’s capabilities as a flight test centre and the approach with respect to the management of flight testing.
    • Shallow Water Training Range

      Reid, Robert; Naval Undersea Warfare Center Division Newport (International Foundation for Telemetering, 1999-10)
      During the cold war, undersea warfare (USW) was perceived as a large-area, deep-water operation. The need for USW has recently shifted to the shallow water, littoral environment. Consequently, US naval forces must train to operate in these littoral environments where regional conflicts are most likely to occur. In light of these requirements the Shallow Water Training Range (SWTR) has been initiated. Telemetry is used in the following areas of SWTR: fiber optic, microwave, RF and underwater. Only phase 1 of 8 phases of the program is executing therefore SWTR is a good opportunity for telemetry industry involvement.
    • COMBINING SENSORS WITH AIRBORNE TELEMETRY INSTRUMENTATION TO MAKE RANGE MEASUREMENTS AND OBTAIN AERODYNAMICS

      Davis, Bradford S.; Brown, T. Gordon; U.S. Army Research Laboratory (International Foundation for Telemetering, 1999-10)
      Obtaining a projectile’s free-flight motion profile and its aerodynamic coefficients is typically accomplished at indoor test ranges using photographic techniques synchronized to timing stations. Since these ranges are relatively short, many discrete tests are necessary to compile a complete understanding of the projectile’s behavior. When Time Space Position Information (TSPI) is requested over long-range flights, it has been gathered with expensive video, laser, and radar trackers. These can be inaccurate at times and are limited to locations where the range equipment is able to track the projectile’s entire flight. With the ever-increasing sophistication of ordnance, such as smart and competent munitions that have multi-stage thrusting and maneuvering capability, it is becoming increasingly difficult to make the necessary measurements using current measurement techniques. Microelectromechanical Systems (MEMS) sensors and other electro-optical and magnetic sensors referenced to the sun and earth allow the projectile’s angular rates (spin, pitch, and yaw) and accelerations (axial and radial) to be measured throughout the flight. These sensors have been packaged into miniaturized telemetry instrumentation systems and placed within empty voids of the munition or in place of the fuze or warhead section. By combining this sensor data with a 6-DOF trajectory code, many of the projectiles aerodynamic coefficients including drag, static moment, and damping moment over a large Mach Number range and over multiple flight paths have been obtained. These techniques decrease the number of test shots required, reduce the complexity of the test setup, and reduce the test costs. Test data from instrumented tank, artillery, and rocket flight tests are presented in this report to show the current capability of making inflight measurements using telemetry-based techniques.
    • ADVANCED SIMULATION TOOLS TO MODEL AND ANALYZE OPERATIONAL ENVIRONMENTS

      Claffey, Douglas J.; Analytical Graphics, Inc. (International Foundation for Telemetering, 1999-10)
      Advances in high-level architectures in both hardware and software now allow 3D software modeling and interactive simulation to be done from the desktop computer. This paper will address the increasing demand for 3D software modeling and simulation applications throughout the aerospace industry, what kinds of tools are currently available, how operational data is being used in real-world applications, and how to couple real-time data with terrain models and simulation tools to model and analyze operational environments. The following specific areas will be addressed: · The creation of real-world environments by merging virtual objects and ground data with interactive simulation and advanced graphics. · Recent advances in software modeling and simulation tools, which mirror general industry trends. · The ongoing effort to establish standards for modeling and simulation applications throughout the aerospace industry. · Examples of applications using high-level architecture-enabling technology like the visual display of detailed terrain data, drag-and-drop imagery, the enhancement of graphical performance without compromising the quality of rendered data, and expanded support for raster file format images.
    • OPTIMIZATION OF REFERENCE WAVEFORM FILTERS IN COHERENT DELAY LOCKED LOOPS

      Gunawardana, Upul; Kosbar, Kurt; Motorola, Inc.; University of Missouri (International Foundation for Telemetering, 1999-10)
      In this paper, a new coherent correlation-loop architecture for tracking direct-sequence spread-spectrum signals is proposed. In the proposed correlation loop model, the mean-square tracking error is minimized by varying the cross-correlation function between the received signal and the locally generated signal. The locally generated signal is produced by passing a replica of the transmitted signal through a linear time-invariant filter, which is termed the VCC filter. The issue of bandwidth of a correlation loop is addressed and a bandwidth definition for comparative purposes is introduced. The filter characteristics to minimize the tracking errors are determined using numerical optimization algorithms. This work demonstrates that the amplitude response of the VCC filter is a function of the input signal-to-noise ratio (SNR). In particular, the optimum filter does not replicate a differentiator at finite signal-to-noise ratio as is sometimes assumed. The optimal filter characteristics and the knowledge of the input SNR can be combined to produce a device that has very low probability of loosing lock.
    • USING SHORT-BLOCK TURBO CODES FOR TELEMETRY AND COMMAND

      Wang, Charles C.; Nguyen, Tien M.; The Aerospace Corporation (International Foundation for Telemetering, 1999-10)
      The turbo code is a block code even though a convolutional encoder is used to construct codewords. Its performance depends on the code word length. Since the invention of the turbo code in 1993, most of the bit error rate (BER) evaluations have been performed using large block sizes, i.e., sizes greater than 1000, or even 10,000. However, for telemetry and command, a relatively short message (<500 bits) may be used. This paper investigates the turbo-coded BER performance for short packets. Fading channel is also considered. In addition, biased channel side information is adopted to improve the performance.
    • DATA-AIDED SYMBOL TIME AND CARRIER PHASE TRACKING FOR PRE-CODED CPM SIGNALS

      Lui, Gee L.; Tsai, Kuang; The Aerospace Corporation (International Foundation for Telemetering, 1999-10)
      A data-aided approach to symbol time and carrier phase synchronization applicable to general continuous phase modulation (CPM) signals with modulation index 0.5 is described. Simulated BER performance of two receivers equipped with these synchronizers is presented for a GMSK BT=1/5 signal received in noise with constant and dynamic synchronization errors. Results demonstrate that these synchronizers provide a very promising and yet simple solution to the tracking problem in the design of coherent CPM receivers.
    • HARDWARE PERFORMANCE FOR BINARY GMSK WITH BT=1/5

      Bow, R. T.; The Aerospace Corporation (International Foundation for Telemetering, 1999-10)
      The design, implementation, and performance of a digital modem employing Gaussian minimum shift keying (GMSK) is described. The GMSK modem is implemented in field programmable gate array (FPGA) chips, and a laboratory test setup was developed to validate its performance for a signal BT value of 1/5. The measured spectrum of the GMSK modem and its bit error rate (BER) performance, which are found in very close agreement with those of theory and simulation, are presented in this paper.
    • PROGRAM MANAGEMENT FOR 2001 INSTRUMENTATION

      Colangelo, Ronald; Simulation, Training and Instrumentation Command (International Foundation for Telemetering, 1999-10)
      The Hardened Subminiature Telemetry and Sensor System (HSTSS) is a model program; executing Department of Defense (DoD) initiatives, such as Acquisition Reform, Industry Partnering, and the use of Integrated Product Teams (IPT). HSTSS is using partnering because the expertise is spread across the industry, and integration is required to fabricate an instrumentation system that would meet tri-service test requirements. This paper will describe the programmatic and technical approaches being used to mitigate risk. In this paper key management strategies will be addressed. I will discuss the affect that the IPT process has had on HSTSS to make the program so successful. This paper will essentially discuss the acquisition strategy as it has evolved to mitigate obsolescence. The strategy has been influenced by acquisition streamlining , commercial technology and the limited production requirements. In this paper I will address how partnering and the use of commercial technology will reduce the program costs as well as the unit cost. The importance of working together within the services and sharing funds and technology to accomplish more with less will be addressed in this paper. This paper will address how we intend to deliver a low cost, microminiature, high g (100,000 g), modular instrumentation system. This instrumentation is to be used for indirect fire and direct fire projectiles and small missiles. Data is to be collected from launch to impact. The modules being developed will include but not be limited to batteries, transmitter, data acquisition chipset and a variety of sensors (pressure, spin rate, GPS, etc.).
    • PROPOSED NEW WAVEFORM CONCEPT FOR BANDWIDTH AND POWER EFFICIENT TT&C

      Olsen, Donald P.; The Aerospace Corporation (International Foundation for Telemetering, 1999-10)
      Most traditional approaches to TT&C have employed waveforms that are neither very power nor bandwidth efficient. A new approach to TT&C waveforms greatly improves these efficiencies. Binary Gaussian Minimum Shift Keying (GMSK) provides a constant envelope bandwidth efficient signal for applications above about 10 Kbps. The constant envelope preserves the spectrum through saturated amplifiers. It provides the best power efficiency when used with turbo coding. For protection against various kinds of burst errors it includes the hybrid interleaving for memory and delay efficiency and packet compatible operations in Time Division Multiple Access (TDMA) environments. Commanding, telemetry, mission data transmission, and tracking are multiplexed in TDMA format.
    • VITERBI AND SERIAL DEMODULATORS FOR PRE-CODED BINARY GMSK

      Lui, Gee L.; Tsai, Kuang; The Aerospace Corporation (International Foundation for Telemetering, 1999-10)
      Three different demodulators applicable to the coherent demodulation of binary Gaussian Minimum Shift Keying (GMSK) signal are described and their performance compared. These include a near-optimal trellis demodulator, which utilizes two matched filters and Viterbi algorithm to carry out maximum likelihood sequence estimation, and a singlefilter threshold demodulator with and without pulse equalization. The performance of these demodulators in noise and adjacent channel interference (ACI) are compared for several signal BT products. The equalized threshold demodulator is shown to perform nearly as well as the near-optimal trellis demodulator in additive white Gaussian noise (AWGN), and substantially outperform the trellis demodulator under severe ACI condition.
    • ARTM CHANNEL SOUNDING RESULTS – AN INVESTIGATION OF FREQUENCY SELECTIVE FADING ON AERONAUTICAL TELEMETRY CHANNELS

      Rice, Michael; de Gaston, David; Davis, Adam; German, Gus; Bettwieser, Christian; Brigham Young University (International Foundation for Telemetering, 1999-10)
      Initial results of wideband channel sounding experiments sponsored by the Advanced Range Telemetry (ARTM) program are presented. Data collected at Edwards EAFB during the Winter 1998-1999, are analyzed in the frequency domain to estimate the number, strength, and delays of the significant multipath reflections observed during the experiments. We observe that the channel is adequately modeled using two or three multipath reflections. The multipath fade events are correlated with recorded bit error rates and transmitter location to provide a comprehensive overview of the channel characteristics. Summaries from two test flights are included where it is seen that the 2- and 3-ray channel models provide excellent models for the data. In general, the 3-ray model captures the essential features of the multipath interference. In this model the first multipath is a strong specular reflection with relative amplitude greater than 0.5 and relative delay in the 30 to 70 ns range. The second multipath is a much weaker reflection with relative amplitude less than 0.5 and relative delay in the 175 to 325 ns range.
    • INSTRUMENTATION AND LOGISTICS: INFLUENCING DESIGN AND OWNERSHIP COSTS

      Phillips, Martin; US Army Simulation (International Foundation for Telemetering, 1999-10)
      A program’s success is measured by the three parameters of cost, schedule and performance. This is true of any acquisition program, including instrumentation development and procurement. The primary purpose of Logistics is to influence and reduce the Total Ownership Costs (TOCs) to the Department of Defense while procuring a supportable system that meets the customer’s needs. The time to influence the TOCs is as early in the life-cycle of the program as can be done - where it is cheapest to affect a “fix.” This paper will briefly describe where Logistics influences ownership costs in the acquisition process. Examples of cost drivers identified in the Hardened Subminiature Telemetry Sensor System (HSTSS) program will be provided and the role of Integrated Product Team (IPT) members in influencing and reducing the TOCs will be discussed. This process is not just in the purview of the traditional logistician, but is also performed by each member of the program’s IPT. Each IPT member brings his unique knowledge and experiences to the teams pool of corporate knowledge. Examples will be provided of decisions made by the IPT that reduced TOCs.
    • INTERACTIVE ANALYSIS AND DISPLAY SYSTEM (IADS) TO SUPPORT LOADS/FLUTTER TESTING

      Williams, Jenny; Lange, Don; Mattingly, Pat; Suszek, Eileen; Edwards Air Force Base (International Foundation for Telemetering, 1999-10)
      The Interactive Analysis and Display System (IADS) provides the structures flight test engineer with enhanced test-data processing, management and display capabilities necessary to perform safety critical aircraft analysis in near real-time during a flight test mission. The IADS provides enhanced situational awareness through an analysis and display capability designed to increase the confidence of the engineer in making clearance decisions within the Mission control Room (MCR) environment. The engineer achieves this confidence level through IADS’ real-time display capability and simultaneous near real-time processing capability consisting of both time domain and frequency domain analyses. The system displays real-time data while performing interactive and automated near real-time analyses; alerting the engineer when displayed parameters exceed predefined threshold limits. Real-time data and results created in near real-time may be compared to previous flight test data to enhance the user’s confidence in making point-to-point clearance decisions. The IADS provides a post flight capability at the engineer’s project area desktop, with a user interface common with the real-time system. The post flight IADS provides all of the capabilities of the real-time IADS with additional data access and data organization, allowing the engineer to perform structural analysis with test data from the each flight and compile summary plots and tables over the most of the test program. The IADS promotes teamwork by allowing the engineers to share data and test results during a mission and in the post flight environment. This paper discusses the system overview and capabilities of the IADS.
    • LINK AVAILABILITY AND BIT ERROR CLUSTERS IN AERONAUTICAL TELEMETRY

      Jefferis, Robert P.; TYBRIN Corporation (International Foundation for Telemetering, 1999-10)
      Radio frequency power margins in well planned line-of-sight (LOS) air-to-ground digital data transmission systems usually produce signal to noise ratios (SNR) that can deliver error free service. Sometimes field performance falls short of design and customer expectations. Recent flight tests conducted by the tri-service Advanced Range Telemetry (ARTM) project confirm that the dominant source of bit errors and short term link failures are “clusters” of severe error burst activity produced by flat fading, dispersive fading and poor antenna patterns on airborne vehicles. This paper introduces the techniques used by ARTM to measure bit error performance of aeronautical telemetry links.
    • Estimating the Characteristics of the Aeronautical Telemetry Channel during Bit Error Events

      Law, Eugene L.; NAWCWD (International Foundation for Telemetering, 1999-10)
      This paper presents estimated aeronautical telemetry channel characteristics during bit error events. A T-39 aircraft was flown around various test corridors while transmitting a filtered 10 Mb/s pseudo-noise (PN) sequence binary phase shift keying (BPSK) signal. The received signal was down converted to 70 MHz, digitized when trigger criteria were met, and stored for later analysis. Received signal strength was also recorded. The first step in data analysis consisted of dividing the fast Fourier transform (FFT) of the recorded signal by the FFT of the expected signal. The received signal strength data was then used to correct for flat fade effects. The resulting signal is the difference (dB) between the expected signal at the receiver intermediate frequency (IF) output and the measured receiver IF output during the error event. This difference is the aeronautical telemetry channel characteristic. The characteristics of this difference signal were then matched against a 2-ray and 3-ray multipath fading model with reflected signal amplitude and path delay as the variables.