• Auto-tracking antenna pattern effects on multipath channel model at test range

      Sung-hoon, Jang; Sung-hee, Han; Heung-bum, Kim; Agency for Defense Development (International Foundation for Telemetering, 2001-10)
      Telemetry propagation channel is modeled to predict PCM/FM telemetry receiving signal level at APG(Anheung Proving Ground), ADD(Agency for Defense Development). Channel model is composed of direct wave and reflected wave in sea surface, so-called 2-ray model. Our 2-ray model includes transmitting antenna radiation pattern, auto-tracking antenna radiation pattern, sea surface reflection coefficient and phase depending on incident angle. Vertical and horizontal polarized receiving signal strength is obtained from pre-calculated flight trajectory of transmitter. Calculated results are compared with measured data in real flight test. 2-ray channel model can predict almost identical receiving signal level and calculate starting point of multi-path fading effect. Using these results, receiving system can be moved to more proper position before flight test.
    • WAVEFORM SIGNAL SHAPING USING WAVELET PARAMETERIZATIONS

      Moon, Todd K.; Noru, Krishna Kishor; Utah State University; Sun Microsystems (International Foundation for Telemetering, 2001-10)
      We explore the idea of matching a scaling function - the basic building block of a wavelet function - to a desired spectrum. This would allow the scaling function to be used as the signal pulse for a digital communication system that is matched to the channel, avoiding problems such as energy loss or noise amplification due to spectral nulls. An unconstrained parameterization of the scaling function coefficients represents the scaling functions. This parameterization is adapted using gradient descent. Tests indicate that the adaptation is able to capture major features of a desired spectrum, including spectral nulls and major lobes.
    • EXPERIMENTAL RESULTS FOR MULTI-SYMBOL DETECTION OF PCM/FM

      Geoghegan, Mark; Nova Engineering Inc. (International Foundation for Telemetering, 2001-10)
      It has been previously shown, through computer simulations, that a multiple symbol detector can provide substantial gains in detection efficiency (nearly 3 dB) over traditional PCM/FM detectors. This is accomplished by performing correlations over multiple symbol intervals to take advantage of the memory inherent in the continuous phase PCM/FM signal. This paper presents measured hardware results, from a prototype developed for the Advanced Range Telemetry (ARTM) Project, that substantiate the previously published performance and sensitivity predictions. Furthermore, this work confirms the feasibility of applying this technology to high-speed commercial and military telemetry applications.
    • ADVANCE PRACTICAL CHANNEL SIMULATORS FOR LEO SATELLITE CHANNELS WITH SELECTIVE FADING AND DOPPLER SHIFTS

      Haghdad, Mehdi; Feher, Kamilo; University of California Davis (International Foundation for Telemetering, 2001-10)
      Dynamic hardware and software schemes for trajectory based simulation of LEO satellite channel are presented and evaluated. The simulation models are based on the practical LEO satellite channels and change dynamically with the trajectory using the latitude and longitude of the LEO satellite as input. The hardware simulator is consisted of a trajectory based selective fade generator, a trajectory based Doppler shifter, trajectory based time shadowing simulator and a standard channel for addition of noise, ACI and CCI. A FQPSK modulated signal is passed through a trajectory based dynamic fade generator and the spectrum is distorted. Then the resulting signal is exposed to a trajectory based dynamic Doppler Shifter, simulating the passage of the satellite overhead. Then the proper AWGN, ACI or CCI is added to the signal. At the final stage the signal is passed through a trajectory based time Shadowing simulator. The software simulator is a dynamic real time simulator written in MatLab and its structure is similar to the hardware simulator.
    • SENSATE-LINER EPLRS TELEMETERED DATA INPUT FOR ENCOMPASS

      Lind, Eric J.; Murray, Steve; Stevens, Ilya; Drozdowski, Nick; SPAWARSYSCEN; High Technology Systems Inc. (International Foundation for Telemetering, 2001-10)
      A systems engineering development for acquisition, transmission, processing, dissemination and display of information vital to combat casualty care and related first responder activities is presented. It utilizes a synergistic combination of two existing state-of-the-art Defense Advanced Research Projects Agency/Space and Naval Warfare Systems Center San Diego (DARPA/SSCSD) technologies (Sensate-Liner and ENCOMPASS) coupled via the Enhanced Position Location Reporting System (EPLRS), an existing wireless military tactical communication data system. Transmission Security and Communication Security (TRANSEC/COMMSEC) of environmental and biomedical data is thus accomplished from the battlefield via selected data links and Ethernet. System functionality and appropriate candidate interfacing technologies will be discussed.
    • SYNTHETIC APERTURE GROUND PENETRATING RADAR IMAGING FOR NONDESTRUCTIVE EVALUATION OF CIVIL AND GEOPHYSICAL STRUCTURES

      Brown, Andrew; Lee, Hua; University of California Santa Barbara (International Foundation for Telemetering, 2001-10)
      Synthetic-aperture microwave imaging with ground penetrating radar systems has become a research topic of great importance for the potential applications in sensing and profiling of civil and geophysical structures. It allows us to visualize subsurface structures for nondestructive evaluation with microwave tomographic images. This paper provides an overview of the research program, ranging from the formation of the concepts, physical and mathematical modeling, formulation and development of the image reconstruction algorithms, laboratory experiments, and full-scale field tests.
    • SATELLITE GROUND OPERATIONS AUTOMATION – LESSONS LEARNED AND FUTURE APPROACHES

      Catena, John; Frank, Lou; Saylor, Rick; Weikel, Craig; National Aeronautics and Space Administration; Honeywell Technology Solutions, Inc.; Computer Sciences Corporation (International Foundation for Telemetering, 2001-10)
      Reducing spacecraft ground system operations costs are a major goal in all missions. The Fast Auroral Snapshot (FAST) flight operations team at the NASA/Goddard Spacecraft Flight Center developed in-house scripts and procedures to automate monitoring of critical spacecraft functions. The initial staffing profile of 16x7 was reduced first to 8x5 and then to “lights out”. Operations functions became an offline review of system performance and the generation of future science plans for subsequent upload to the spacecraft. Lessons learned will be applied to the challenging Triana mission, where 24x7 contact with the spacecraft will be necessary at all times.
    • A SMALL SATELLITE FOR MEASURING ATMOSPHERIC WATER CONTENT; PART I, DOWNLINK AND COMMAND SYSTEMS

      Schooley, L. C.; Cramer, J.; Biggs, B.; Contapay, J.; Iskandar, A.; Mahan, A.; University of Arizona (International Foundation for Telemetering, 2001-10)
      This student paper was produced as part of the team design competition in the University of Arizona course ECE 485, Radiowaves and Telemetry. It describes a telemetering system design recommendation for a small satellite capable of conducting scientific research regarding atmospheric water content. This paper focuses on the subsystems required to send the scientific data and monitored operational conditions from the satellite to, and commands to the satellite from, a ground station. A companion paper (Hittle, et. al.) focuses on the cross-link subsystem required to make the scientific measurements and on the power generation and distribution subsystem for the satellite.
    • PYROTECHNIC SHOCK AND RANDOM VIBRATION EFFECTS ON CRYSTAL OSCILLATORS

      Carwell, James W.; CMC Electronics Cincinnati (International Foundation for Telemetering, 2001-10)
      Today’s telemetry specifications are requiring electronic systems to not only survive, but operate through severe dynamic environments. Pyrotechnic shock and Random Vibration are among these environments and have proven to be a challenge for systems that rely on highly stable, low phase noise signal sources. This paper will mathematically analyze how Pyrotechnic shock and Random Vibration events deteriorate the phase noise of crystal oscillators (XO).
    • LESSONS LEARNED AND PROCESS IMPROVEMENT FOR PAYLOAD OPERATIONS AT THE LAUNCH SITE

      Catena, John; Gates, Donald, Jr.; Blaney, Kermit, Jr.; National Aeronautics and Space Administration; Omitron, Inc. (International Foundation for Telemetering, 2001-10)
      For every space mission, there are challenges with the launch site/field operations process that are addressed too late in the development cycle. This potentially causes schedule delays, cost overruns, and adds risk to the mission success. This paper will discuss how a single interface, representing the payload at the launch site in all phases of development, will mitigate risk, and minimize or even alleviate potential problems later on. Experience has shown that a single interface between the project and the launch site allows for issues to be worked in a timely manner and bridges the gap between two diverse cultures.
    • Precious Bits: Frame Synchronization in Jet Propulsion Laboratory's Advanced Multi-Mission Operations System (AMMOS)

      Wilson, Elizabeth (Betsy); Jet Propulsion Laboratory (International Foundation for Telemetering, 2001-10)
      The Jet Propulsion Laboratory’s (JPL) Advanced Multi-Mission Operations System (AMMOS) system processes data received from deep-space spacecraft, where error rates are high, bit rates are low, and every bit is precious. Frame synchronization and data extraction as performed by AMMOS enhance data acquisition and reliability for maximum data return and validity. Unique aspects of data phase determination, sync acquisition and sync loss and other bit-level topics are covered.
    • THE ART OF INTERNATIONAL SPACE STATION TELEMETRY BANDWIDTH MANAGEMENT

      Cerna, Peter J.; Klein, Pamela R.; Mullett, Joy; National Aeronautics and Space Administration; United Space Alliance; Hernandez Engineering, Inc. (International Foundation for Telemetering, 2001-10)
      The technicalities of sharing telemetry bandwidth have been addressed in design and specification for the builders of the International Space Station. But success in sharing bandwidth comes from building relationships, documenting guidelines, negotiating, understanding human nature, peer review and willingness to participate in an evolving process. The station, 240 miles above Earth, moves through space at 17,000 mph, has its mass added to by humans and machines, regularly docks with visiting spacecraft, has year-round residents, and communicates with space agencies around the globe. Each new module -- with associated computers, multiplexers, and communications buses -- creates additional telemetry demands.
    • A SMALL SATELLITE FOR MEASURING ATMOSPHERIC WATER CONTENT; PART II, CROSSLINK AND DATA COLLECTION

      Schooley, L. C.; Hittle, K.; Braga, A.; Ackerman, R.; Afouni, F.; Khalid, H.; Coleman, J.; Keena, T.; Page, A.; University of Arizona (International Foundation for Telemetering, 2001-10)
      This student paper was produced as part of the team design competition in the University of Arizona course ECE 485, Radiowaves and Telemetry. It describes a telemetering system design recommendation for a small satellite capable of conducting scientific research regarding atmospheric water content. This paper focuses on the cross-link subsystem required to make the scientific measurements and on the power generation and distribution subsystem for the satellite. A companion paper (Cramer, et. al.) focuses on the subsystems required to send the scientific data and monitored operational conditions from the satellite to, and commands to the satellite from, a ground station. The central objective is to validate a new technique for precisely measuring water vapor profiles of clouds throughout the troposphere. This method involves the detection of 4 SHF tones sent out from the International Space Station (ISS), providing high-resolution amplitude and phase delay data.
    • REENGINEERING A TRADITONAL SPACECRAFT CONTROL CENTER

      Knauer, Christian; Nötzel, Klaus Ralf; CAM GmbH; Deutsche Telekom AG (International Foundation for Telemetering, 2001-10)
      Deutsche Telekom is operating various communication satellites since 1989. The SCC (spacecraft control center) is located near Frankfurt / Germany. The entire system is based on antenna/RF equipment, baseband and computer software packages running on a computer network of different machines. Due to increased maintenance effort the old baseband system needed to be replaced. This also had effects to the computer system, especially to the M&C. The aim was to design the entire system in a way that the operation effort in costs aspects and human intervention are minimized. This paper shows the successful real world project of reengineering a traditional spacecraft control center (SCC). It is shown how a fifteen year old hardware (baseband system) and software design was replaced by a modern concept during normal operations. The new software packages execute all necessary tasks for spacecraft- and ground station control. The Monitor and Control System (M&C) is a database driven design (FRAMTEC, from CAM Germany).
    • VIDEO COMPRESSION DECK FOR A MODULAR FLIGHT PCM ENCODER SYSTEM

      Gammill, Troy; Stoner, Mark; New Mexico State University (International Foundation for Telemetering, 2001-10)
      Overview of video compression modules developed and flown as part of PSL’s flight-proven family of modular PCM components. Wavelet based video compression deck is compatible with PCM Encoder modules, allowing video to be included in instrumentation data stream. Video compression modules allow the user to select video frame rate and video quality, supports 8-16 bits/word, and non-symmetrical PCM matrices. Video Compression and formatting is achieved with a wavelet compression IC and specialized DSP code. Video output is achieved with PSL PCM Decommutator and Video Decompression Module.
    • MAGNETIC ROLL SENSOR FOR ROLLING AIRFRAMES

      Meyer, Steven; Naval Air Warfare Center Weapons Division (International Foundation for Telemetering, 2001-10)
      Measuring the roll rate or roll position of a rolling airframe can be difficult. Some of the smaller missiles, which have roll rates in excess of 20 revolutions per second, have the least amount of room for a roll sensor such as a laser ring gyro or a quartz rate sensor. The large roll rates coupled with the rate sensor’s resolution can cause large errors in just a few seconds. The cost for these devices can be very high. The roll problem on rolling airframes has been solved by using two magnetic sensors that are 90 degrees out of phase from each other to measure the roll. The cost of the sensor is approximately $15 and is packaged in a 20-pin-surface-mount device. This paper addresses the design and the data processing algorithm to produce roll position. The sensor and algorithm were checked for accuracy on a CARCO table.
    • SERVING INTERACTIVE WEB PAGES TO TechSat21 CUSTOMERS

      Self, Lance; Kirtland Air Force Base (International Foundation for Telemetering, 2001-10)
      TechSat21 is an innovative satellite program sponsored by the Air Force Research Laboratory Space Vehicles Directorate and the Air Force Office of Scientific Research. Its mission is to control a cluster of satellites that, when combined, create a “virtual satellite” with which to conduct various experiments in sparse aperture sensing and formation flying. Because TechSat21 customers have a need to view very large data sets that vary from the payload to the satellite state of health1 a modern viewing method using Java Server Pages and Active Server Pages is being developed to meet these interactive dynamic demands.
    • APPLYING INTERACTIVE WEB PAGES

      Self, Lance; Kirtland Air Force Base (International Foundation for Telemetering, 2001-10)
      Visitors to web pages are, in most cases, restricted to viewing information the page designer has anticipated they will be interested in viewing. Many times this is adequate, but there are instances where the visitor wants the information they view to be based on selections they choose. The Air Force Research Laboratory (AFRL) Space Vehicles Directorate anticipates selected customers will have a need to view very large data sets that vary from the satellite payload to the satellite state of health1, and will require controlling what they view in an “ad hoc” manner. In response, AFRL is using Java Server Pages developed within the data center to bring interactive and dynamic web page content to these customers.
    • CONCEPTUAL DESIGN OF CENTIMETER ACCURACY LOCAL POSITIONING SYSTEM

      Annamraju, Venu; Kosbar, Kurt; University of Missouri – Rolla (International Foundation for Telemetering, 2001-10)
      This project investigates the feasibility of position detection in an office or industrial setting. The objective is to design a low-cost positioning system that uses the unlicensed 5.7 GHz ISM band, with centimeter accuracy and limited range. During the conceptual design phase of the system, indoor channel models will be investigated to determine which of a variety of architectures will be useful. For triangulating the position, an array of widely spaced stationary receivers and a mobile transmitter is proposed.
    • Generating Spread-Spectrum Sequences by a Class of Chaotic Maps

      Chengquan, Au; Tingxian, Zhou; Yuxiang, Yang; Harbin Institute of Technology (International Foundation for Telemetering, 2001-10)
      Based on the fact that two topological conjugacy chaotic maps have identical dynamical behaviors, this paper proposes a method generating spreadspectrum sequences by creating chaotic maps topological conjugacy to Kent- Map, and analyses the correlation properties of the chaotic spread-spectrum sequences. The results of simulation verified the correctness of the theoretical analysis.