• DOPPLER BANDWIDTH CHARACTERIZATION OF ARTM CHANNEL SOUNDING DATA

      Rice, Michael; Landon, David; Brigham Young University (International Foundation for Telemetering, 1999-10)
      Data from ARTM channel sounding test flights is examined to characterize the dynamic channel behavior of aeronautical telemetry channels. The dynamic behavior is characterized using the Doppler power spectrum. The width of the Doppler power spectrum is the Doppler bandwidth of the channel which indicates the required bandwidth of adaptive detection techniques such as adaptive equalization, adaptive modulation, adaptive channel selection and adaptive error control coding. Data collected from ARTM Flight 11 suggest a Doppler bandwidth exceeding 6.7 Hz for the channel, but greater accuracy and resolution will only be possible with more data.
    • ADVANCED RANGE TELEMETRY DYNAMIC MEASUREMENT LISTS

      Luten, Robert H.; Diekmann, Vernon; Luten Data Systems; Tybrin Corp. (International Foundation for Telemetering, 1999-10)
      A typical telemetry system for aircraft flight-testing transmits one or several data streams to the ground for real-time display and analysis, and also records the same stream onboard for later playback. During test operations, only a fraction of the available data is used at any given time for real-time display or analysis. More efficient use of the RF channel could be realized if only the data needed for the current test point is transmitted, rather than the entirety of the data. Intelligent selection of a subset of the data stream can provide large reductions in the required telemetry downlink bandwidth. As one of the Advanced Range Telemetry (ARTM) On-Board Data Management (OBDM) initiatives, a prototype on-board data selection subsystem is being developed and demonstrated. The demonstration utilizes COTS telemetry workstations to the maximum extent possible and includes “plug-in” data requestor, selection, and server components to implement the added DML functionality. A significant objective of the OBDM/DML project will be to validate RF channel models to help minimize the amount of flight-testing necessary to validate the DML concept. This paper will discuss the OBDM/DML architecture, integration of several custom components with the COTS portions of the ARTM “test bench”, and the current status of the OBDM/DML development and test program.
    • 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.
    • 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.
    • 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.
    • COMBINING TECHNOLOGIES TO FOSTER IMPROVED TSPI ACCURACY AND INCREASE SHARING OF THE FREQUENCY SPECTRUM

      Switzer, Earl R.; Wrin, John; Huynh, James; Air Force Flight Test Center; TYBRIN Corporation (International Foundation for Telemetering, 1999-10)
      The loss of radio frequency (RF) spectrum for use in testing has steadily increased the likelihood that users of the few remaining frequencies available to test ranges will experience scheduling conflicts and interference with nontest users. A gradual increase in the base of test customers engaged in scientific, military, and commercial R&D, point toward a near term situation in which more test customers will be competing for fewer frequencies. The test ranges, often operating in close geographical proximity with other communications-intensive functions as well as with each other, will also encounter increasing out-of-band and adjacent-channel interference. This projected growth of R&Drelated testing constrained to operate in a diminished RF spectrum (and a more confined test space), will undoubtedly stimulate the development of new products that make more efficient use of the RF spectrum. This paper describes one such innovative approach to spectrum sharing. The authors assess the operational need for an affordable miniaturized avionics instrument package based on a C-band radar transponder integrated with a Global Positioning System/Inertial Measurement Unit (GPS/IMU). The proposed approach would make use of frequencies already allocated for use by existing C-band aeronautical transponders. It would augment the format of the transponder output data to include the vehicle position obtained from an onboard GPS/IMU. Existing range instrumentation radars, such as the venerable AN/FPS-16, could be modified with lowcost upgrade kits to provide uniformly higher accuracy over the entire transponder coverage range.
    • FLEXIBLE ALL-DIGITAL RECEIVER FOR BANDWIDTH EFFICIENT MODULATIONS

      Gray, Andrew; Srinivasan, Meera; Simon, Marvin; Yan, Tsun-Yee; California Institute of Technology (International Foundation for Telemetering, 1999-10)
      An all-digital high data rate parallel receiver architecture developed jointly by Goddard Space Flight Center and the Jet Propulsion Laboratory is pre- sented. This receiver utilizes only a small number of high speed components along with a majority of lower speed components operating in a parallel fre- quency domain structure implementable in CMOS, and can process over 600 Mbps with numerous varieties of QPSK modulation, including those incorpo- rating precise pulse shaping for bandwidth eÆcient modulation. Performance results for this receiver for bandwidth eÆcient QPSK modulation schemes such as square-root raised cosine pulse shaped QPSK and Feher’s patented QPSK are presented, demonstrating the great degree of exibility and high performance of the receiver architecture.
    • MATCHED FILTER-BOUND OF BANDWIDTH EFFICIENT MULTISCALE WAVELET SIGNALING OVER MULTIPATH RAYLEIGH FADING CHANNELS

      Lo, Chet; Moon, Todd K.; Utah State University (International Foundation for Telemetering, 1999-10)
      In this paper, we extended the matched filter bound (MFB) of time-discrete multipath Rayleigh fading channels derived in [1,2] for multiscale wavelet signaling communication.
    • Bandwidth Efficient Signaling Using Multiscale Wavelet Functions and its Performance in a Rician Fast Fading Channel Employing Differential Detection

      Moon, Todd K.; Lo, Chet; Utah State University (International Foundation for Telemetering, 1999-10)
      In this paper, orthogonal wavelets are employed to produce multiscale signaling. It is shown that signaling using these functions is bandwidth efficient compared other signaling schemes, including SFSK and GMSK. For signaling in Rician fast fading channel, it is also shown that scaling functions is superior in term of achieving low level of probability of error. Even for multiscale signaling, the level probability of error achieved by using wavelet is lower than conventional flat-top signaling. The benefits are largest for channels with small B(D)T , in which the degradation due to fading is most severe.
    • HYPERSPECTRAL IMAGE COMPRESSION

      Hallidy, William H., Jr.; Doerr, Michael; Systems & Processes Engineering Corporation (International Foundation for Telemetering, 1999-10)
      Systems & Processes Engineering Corporation (SPEC) compared compression and decompression algorithms and developed optimal forms of lossless and lossy compression for hyperspectral data. We examined the relationship between compression-induced distortion and additive noise, determined the effect of errors on the compressed data, and showed that the data could separate targets from clutter after more than 50:1 compression.
    • DATA COMPRESSION STATISTICS AND IMPLICATIONS

      Horan, Sheila; New Mexico State University (International Foundation for Telemetering, 1999-10)
      Bandwidth is a precious commodity. In order to make the best use of what is available, better modulation schemes need to be developed, or less data needs to be sent. This paper will investigate the option of sending less data via data compression. The structure and the entropy of the data determine how much lossless compression can be obtained for a given set of data. This paper shows the data structure and entropy for several actual telemetry data sets and the resulting lossless compression obtainable using data compression techniques.
    • AN INTRODUCTION TO SPECTRUM REALLOCATION LEGISLATION

      Ryan, Mikel R.; Naval Air Warfare Center Aircraft Division (International Foundation for Telemetering, 1999-10)
      In the past four years Congress has passed legislation mandating the reallocation of 255 MHz of radio frequency bands from Federal to non-Federal or “MIXED USE.” Several of the frequency bands supporting telemetering functions were affected, and more legislation of this nature is forecasted.
    • LEVERAGING GOVERNMENT AND COMMERCIAL INVESTMENTS

      D’Amico, William P.; US Army Research Laboratory (International Foundation for Telemetering, 1999-10)
      It is tempting to conceive a program that is self-contained and to fiscally control the all the necessary developments. Such a path will lead to a program that is technically stovepiped and extremely expensive. For the test and evaluation (T&E) community, products are often developed only for single application. We do not exist in such times. The use of other program’s products and commercial products is basically required. This is the path that the Hardened Subminiature Telemetry and Sensor System (HSTSS) has taken. The HSTSS philosophy required that the technologies common to telemetry systems be examined for reduction in cost, size, ease of use, and above all the survivability under high-g or high shock environments. It was clear that HSTSS could not support all of these requirements for transmitters, batteries, electronic packaging, and sensors and be realistically affordable with a good return on investment. This paper describes how the HSTSS program has accomplished the development of new batteries, transmitters, and data acquisition devices based upon a leveraged acquisition strategy.
    • HSTSS-DAC CUSTOM ICS IMPACT ON 2.75" MISSILE TELEMETRY

      Gibson, David A.; Penrose, Newton B.; Wade, Ralph B., Jr.; Systems & Processes Engineering Corporation (SPEC); Eglin Air Force Base (International Foundation for Telemetering, 1999-10)
      We analyze several telemetry data acquisition systems to gage the system impact of denser custom ICs being developed under the HSTSS-DAC project. Our baseline is a telemetry system recently developed at Eglin AFB to support 16 analog input channels, signal conditioning and encoding for Pulse Code Modulation (PCM) using Commercial Off-the- Shelf (COTS) ICs. The data acquisition portion of the system occupies three double-sided, round circuit cards, each 2.3" in diameter. A comparable system using HSTSS-DAC custom Ics will occupy only one side of one card - a factor of six-volume reduction compared to the COTS approach.
    • Digital FDM for the HSTSS DAC Program

      Doerr, Michael B.; Hallidy, William H., Jr.,; McMillian, Gary B.; Burke, Lawrence W., Jr.; Faust, Jonah N.; Systems & Processes Engineering Corporation; U. S. Army Research Laboratory (International Foundation for Telemetering, 1999-10)
      This paper presents the design of an innovative approach to Frequency Division Multiplexing (FDM) for the STRICOM Hardened Subminiature Telemetry and Sensor System (HSTSS) Data Acquisition Chipset (DAC) program. An ASIC (Application Specific Integrated Circuit) is being developed by Systems & Processes Engineering Corporation (SPEC) that implements this new digital FDM approach for telemetry applications. The FDM ASIC provides six channels that are IRIG-106 compatible, and may be used in conjunction with a Delay/Repeater ASIC. Together these ASICs make a complete instrumentation system for those applications requiring very small size, simplicity of use, and low cost, e.g. munitions/armament testing.
    • HSTSS-DAC CUSTOM INTEGRATED CIRCUITS FOR SUBMINIATURE PCM TELEMETRY AND SIGNAL CONDITIONING

      Gibson, David; Penrose, N.B.; Doerr, Michael; Borgen, Gary; Systems & Processes Engineering Corporation (SPEC); Naval Air Warfare Center Weapons Division (International Foundation for Telemetering, 1999-10)
      To meet specific test and evaluation requirements, the Hardened Subminiature Telemetry and Sensor Systems (HSTSS) program is addressing the miniaturization and ‘G’ hardening of telemetry components. Two custom Integrated Circuits (ICs) are in development to support the design of miniature Pulse Code Modulation (PCM) systems with up to 128 analog input channels. This paper describes the design and development of the custom IC chips of the HSTSS Data Acquisition Chipset (DAC). The original requirements, the roll of the Integrated Product Team (IPT), design decisions, a discussion of the additional features, and practical limitations of the Data Acquisition Chipset will be covered.
    • THE APPLICATION OF HARDENED CRYSTAL REFERENCE OSCILLATORS INTO THE HARDENED SUBMINIATURE TELEMETRY AND SENSOR SYSTEM (HSTSS) PROGRAM

      Hart, Alan D.; US ARMY YUMA PROVING GROUND (International Foundation for Telemetering, 1999-10)
      This paper briefly reports on concepts for hardening (physically toughening) crystal reference oscillators for the highly integrated program known as HSTSS. Within the HSTSS program is the L & S band transmitter development contract. The harshest requirements for this contract are surviving and functioning, to within 20 ppm of its center frequency, 30 ms after sustaining a shock pulse of 100,000 (g) for 0.5 ms on any axis. Additional requirements call for the transmitter to be no larger than 0.2 in3, and to operate within a 20 ppm frequency stability throughout the temperature range of -400 to +850 centigrade and during centrifugal spins of up to 300 Hz or 25,000 (g). Fundamentally the question is, is it feasible for any telemetry system to be capable of withstanding such harsh conditions and, to be practical on all DoD Test Ranges, still adhere to the stability tolerance guidelines set forth by the Range Commanders Council on Telemetry Standards - IRIG 106-96? Under "normal" conditions, stability requirements for "Range" transmitters are easily satisfied through the use of off-the-shelf crystal reference oscillators which provide the reference frequencies required within a transmitter’s phase lock loop circuitry. Unfortunately, the oscillator is also the most vulnerable part of a transmitter to the conditions listed and is the key to this problem. The oscillator’s weak points are in its resonator’s fragile quartz structure (the blank) and support mechanism. The challenge is to invent and adapt this area to these newer harsher conditions and to do it in the smallest space ever required.
    • A Modular Approach to Hardened Subminiature Telemetry and Sensor System (HSTSS) Development

      Carpenter, Robert E.; Schneider, Dennis; Advanced Systems Technology, Inc.; Simulation Training and Instrumentation Command (STRICOM) (International Foundation for Telemetering, 1999-10)
      In the past, typical telemetry systems for munitions and small missiles have often comprised adaptations of monolithic components originally conceived for aircraft or large missile applications. Programs have developed expensive monolithic systems to meet the needs of specific programs, but they often require extensive redesign for use by other potential users. The tri-service HSTSS Integrated Product Team (IPT) determined that a monolithic “one size fits all” approach has technical and fiscal risks. Thus, a modular approach to system development has been adopted. The HSTSS IPT is flight qualifying commercial microelectronic products designed for environments similar to that of munition interiors, and is developing microelectronic components required to complete a subminiature system. HSTSS components can then be integrated to support the form factor and measurement needs of any given user. In addition to offering a flexible system to the user, the HSTSS lends itself to upgradability (modernization through spares).
    • 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.
    • 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.