• A Multi-Pulse PPK Telemetry System Based on PC

      Jian, Zhang; Ming-Sheng, Huang; Xinan Electronic Engineering Institute (International Foundation for Telemetering, 1995-11)
      A new kind of telemetry ground data system--Multi-Pulse PPK (Pulse Position Keying) Telemetry System Based on PC(MPPK-PCTS) is presented in this paper. Being Aimed at the lower bit rate which is the essential shortcoming of Single-Pulse PPK(SPPK), Multi-Pulse PPK(MPPK) signal is introduced to this system. Its signal forms, bit rate, energy efficiency and error probability have been analysed in detail. The symmetric Bi-Pulse PPK(BPPK) signal with fixed reference pulse can be practised in engineering. In this system, front-ends are intelligent and modular, all modules are integrated in a personal computer chassis through EISA/PCI bus. The system operates under multi-media WINDOWS environment, with intelligent user interface. Faults can be detected and located automatically. With flexible performance, good expandibility and small size, the system can be used in reentry telemetry and many other fields where higher rate and lower power are both required.
    • Integrated CCSDS, SGLS and STDN Telemetry, Tracking and Command Processing System

      Nichols, Alex; Goodstein, F. Robert; VanCouvering, Ken; TRW Components International; TRW Inc. (International Foundation for Telemetering, 1995-11)
      This paper describes the use of an open architecture, low-cost, turnkey Telemetry, Tracking and Command (TT&C) processor system. The workstation based system was developed to satisfy the requirement for ground station equipment to handle and process multiple vehicle platforms for telemetry, command and tracking (tone or PRN), including STDN, SGLS and CCSDS link formats. The open architecture of the system allows for easy interface with external equipment for control of antenna systems, encryption units and other related station equipment. Reconfiguration for the various data formats and for system verification is done through a graphical user interfaces using operationally proven commercial-off-the-shelf (COTS) software and hardware. The open architecture of the system will allow for modifications and upgrades to be cost effective.
    • The Use of Non-Linear Amplifier Models in Bandlimited Channels

      Ross, Michael D.; Osborne, William P.; Jean-Baptiste, Gregory (International Foundation for Telemetering, 1995-11)
      The non-linear operating characteristics of efficient, high-powered amplifiers has motivated the development of constant envelope signaling schemes for satellite, mobile, and range communications. As such applications face demands for greater spectral efficiency, it has become useful to re-examine non-linear amplifiers with respect to spectral regrowth of filtered signals, and the performance of non-constant envelope signaling. This paper examines the use of amplifier models, empirical measurements, and software tools in the development of spectrally efficient QAM signal schemes.
    • The Merging of Multisource Telemetry Data to Support Over the Horizon Missile Testing

      Peterson, Dwight M.; Naval Warfare Assessment Division (International Foundation for Telemetering, 1995-11)
      The testing of instrumented missile systems with extended range capabilities present many challenges to existing T&E and training ranges. Providing over-the-horizon (OTH) telemetry data collection and displaying portions of this data in real time for range safety purposes are just a few of many factors required for successful instrumented range support. Techniques typically used for OTH telemetry data collection are to use fixed or portable antennas installed at strategic down-range locations, instrumented relay pods installed on chase aircraft, and instrumented high flying relay aircraft. Multiple data sources from these various locations typically arrive at a central site within a telemetry ground station and must be merged together to determine the best data source for real time and post processing purposes. Before multiple telemetered sources can be merged, the time skews caused by the relay of down-range land and airborne based sources must be taken into account. The time skews are fixed for land based sources, but vary with airborne sources. Various techniques have been used to remove the time skews associated with multiple telemetered sources. These techniques, which involve both hardware and software applications, have been effective, but are expensive and application and range dependent. This paper describes the use of a personal computer (PC) based workstation, configured with independent Pulse Code Modulation (PCM) decommutators/bit synchronizers, Inner-Range Instrumentation Group (IRIG) timing, and data merging resident software to perform the data merging task. Current technology now permits multiple PCM decommutators, each built as a separate virtual memory expansion (VME) card, to be installed within a PC based workstation. Each land based or airborne source is connected to a dedicated VME based PCM decommutator/bit synchronizer within the workstation. After the exercise has been completed, data merging software resident within the workstation is run which reads the digitized data from each of the disk files and aligns the data on a bit by bit basis to determine the optimum merged result. Both time based and event based alignment is performed when merging the multiple sources.This technique has application for current TOMAHAWK exercises performed at the Air Force Development Test Center, Eglin Air Force Base (AFB), Florida and the Naval Air Warfare Center/Weapons Division (NAWC/WD), Point Mugu, California and future TOMAHAWK Baseline Improvement Program (TBIP) testing.
    • FM/FM Preemphasis Schedule Design for Concurrent All Channel Dropout and Minimum Transmission Bandwidth

      Carden, Frank; New Mexico State University (International Foundation for Telemetering, 1995-11)
      This work is concerned with the design of the FM/FM preemphasis schedule such that all channel dropout occurs concurrently in that threshold is reached at the same signal-to noise ratio at the same time in all the channels. That is, threshold occurs in the carrier IF at the same time as threshold occurs in all the subcarrier bandpass filters. This design assures that this is the minimum transmission bandwidth achievable with no channel in threshold. The procedure developed is a systematic approach to the design of the preemphasis schedule that is readily converted to an algorithmic code. When the code is implemented on a computer, the preemphasis schedule may be modified and studied for various anticipated operational parameters such as carrier-to-noise ratio at the receiver and the D(si)'s. The impact on the output signal-to-noise ratios by the specified D(si)'s can also be evaluated. A design examples is given.
    • An ACTS Mobile Receiver Simulation

      Mott, Brian J.; Wise, Kevin D.; Brigham Young University (International Foundation for Telemetering, 1995-11)
      The continuing demand for mobile communication and the growing congestion of currently assigned frequency bands has precipitated the development of K/Ka band mobile-satellite technology. The Jet Propulsions Lab (JPL), using the Advanced Communications Technology Satellite (ACTS), has conducted prototype testing of a K/Ka band mobile-satellite link. The JPL system uses a narrow beam antenna which tracks the satellite signal. As the JPL vehicle experienced changes in yaw, pitch, and roll, the antenna experienced a pointing error. A model to describe the power losses caused by pointing error is developed. This model shows a received power loss on the order of 2.0 dB.
    • Digitally Recorded Data Reduction on a PC Using CAPS

      Rarick, Michael J.; Lawrence, Ben-z (International Foundation for Telemetering, 1995-11)
      The Common Airborne Processing System (CAPS) provides a general purpose data reduction capability for digitally recorded telemetry data on a cost-efficient platform. Telemetry data can be imported from a variety of formats into the CAPS standard file format. Parameter dictionaries describing raw data structures and output product descriptions describing the desired outputs can be created and edited from within CAPS. All of this functionality is performed on an IBM compatible personal computer within the framework of the graphical user interface provided by Microsoft Windows.
    • BYU SAR: A Low Cost Compact Synthetic Aperture Radar

      Long, David G.; Jarrett, Bryan; Arnold, David V.; Cano, Jorge (International Foundation for Telemetering, 1995-11)
      Synthetic Aperture Radar (SAR) systems are typically very complex and expensive. They generate enormous quantities of data, requiring very high capacity data storage, transmission, and processing systems. We have developed an experimental SAR system with a very simple design which includes near-real-time onboard processing. This system is based on recent developments in low-cost, high-rate analog-to-digital (A/D) and digital-to-analog (D/A) data conversion systems. Most of the system is based on off-the-shelf components. A very simple RF subsystem is used. The system has been successfully operated from a moving surface vehicle and exhibits a range resolution of 2.5 m though this could be improved to 1.5 m at the expense of higher sidelobes. The four look azimuth resolution is 0.4 m. This paper describes the system as well as our plans for upgrading the system for aircraft operation and improved resolution.
    • An Analysis of Various Digital Filter Types for Use as Matched Pre-Sample Filters in Data Encoders

      Hicks, William T. (International Foundation for Telemetering, 1995-11)
      The need for precise gain and phase matching in multi-channel data sampling systems can result in very strict design requirements for presample or anti-aliasing filters. The traditional use of active RC-type filters is expensive, especially when performance requirements are tight and when operation over a wide environmental temperature range is required. New Digital Signal Processing (DSP) techniques have provided an opportunity for cost reduction and/or performance improvements in these types of applications. This paper summarizes the results of an evaluation of various digital filter types used as matched presample filters in data sampling systems.
    • Shrinking the Cost of Telemetry Frame Synchronization

      Ghuman, Parminder; Bennett, Toby; Solomon, Jeff; NASA, Goddard Space Flight Center; RMS Technologies Inc. (International Foundation for Telemetering, 1995-11)
      To support initiatives for cheaper, faster, better ground telemetry systems, the Data Systems Technology Division (DSTD) at NASA Goddard Space Flight Center is developing a new Very Large Scale Integration (VLSI) Application Specific Integrated Circuit (ASIC) targeted to dramatically lower the cost of telemetry frame synchronization. This single VLSI device, known as the Parallel Integrated Frame Synchronizer (PIFS) chip, integrates most of the functionality contained in high density 9U VME card frame synchronizer subsystems currently in use. In 1987, a first generation 20 Mbps VMEBus frame synchronizer based on 2.0 micron CMOS VLSI technology was developed by Data Systems Technology Division. In 1990, this subsystem architecture was recast using 0.8 micron ECL & GaAs VLSI to achieve 300 Mbps performance. The PIFS chip, based on 0.7 micron CMOS technology, will provide a superset of the current VMEBus subsystem functions at rates up to 500 Mbps at approximately one-tenth current replication costs. Functions performed by this third generation device include true and inverted 64 bit marker correlation with programmable error tolerances, programmable frame length and marker patterns, programmable search-check-lock-flywheel acquisition strategy, slip detection, and CRC error detection. Acquired frames can optionally be annotated with quality trailer and time stamp. A comprehensive set of cumulative accounting registers are provided on-chip for data quality monitoring. Prototypes of the PIFS chip are expected in October 1995. This paper will describe the architecture and implementation of this new low-cost high functionality device.
    • CCSDS in the Loral 550

      Sutton, Jerry; Taylor, Larry; Loral Test & Information System (International Foundation for Telemetering, 1995-11)
      The Consultative Committee on Space Data Systems (CCSDS) did not create a specification like the IRIG 106, but rather a recommendation [1-4]. That means that each country, community, and application is free to select subsets, adapt techniques, and even alter the structure to suit particular needs. This variability places new demands on a decommutation system. The implementation of the CCSDS Recommendation in the Loral 550 accommodates this "variability within a structure" by using a modular and adaptable collection of structured components. The result covers the two most popular versions of CCSDS: Conventional/Telecommand and the Advanced Orbital Systems (AOS) in both operational and test modes, and couples the CCSDS inputs and outputs to a host of other data format and processing options.
    • Implementing an Open Setup Environment Across Multiple Vendor Products Using TMATS

      Comperini, Robert G.; Scardello, Michael A.; Perimeter Computer Systems (International Foundation for Telemetering, 1995-11)
      The Inter-Range Instrumentation Group (IRIG) introduced the Telemetry Attributes Transfer Standard (TMATS) in IRIG 106-93. This long needed standardization was designed to provide a common thread through which test programs could move from one test range to another without significant re-work in the setup environment. TMATS provides the definition of telemetry attributes and specifies the media and data format necessary to permit the ready transfer of the information required to setup telemetry receiving/processing functions at a test range. These attributes are defined as those parameters required by the receiving/processing system to acquire, process and display telemetry data received from a test item or source. As the telemetry vendor community develops more and more board level products designed to be integrated into various platforms such as Personal Computer (PC), VME, and VXI, the necessity of providing a setup environment, which is independent of a specific vendor product, becomes essential. An significant advantage of TMATS lies in its ability to provide a mechanism for setup of "multiple vendor systems" without the necessity of restructuring telemetry attribute information for each unique vendor's product. This paper describes the use of TMATS for the setup of a VXI based telemetry acquisition system containing board level products (including Antenna Control Units, RF Receivers, Combiners, Bit Synchronizers, PCM Decommutators, and PCM Simulators) from multiple vendors.
    • The New Generation Spacecraft Data Simulator to Test Level Zero Processing Systems

      Michandani, Chandru; Kozlowski, Chuck; Bennett, Toby; Loral AeroSys; RMS Technologies; NASA, Goddard Space Flight Center (International Foundation for Telemetering, 1995-11)
      Over the last several years, the Data Systems Technology Division (DSTD) at Goddard Space Flight Center (GSFC) has developed software tools to generate simulated spacecraft data to support the development, test, and verification of prototype and production of its Very Large Scale Integration (VLSI) telemetry data systems. Recently, these data simulation tools have demonstrated their versatility and flexibility in the testing and deployment of several very high performance Level Zero Processing (LZP) systems. Because LZP involves the wide scale reordering of transmitted telemetry data, the data simulation tools were required to create a number of very large and complex simulated data sets to effectively test these high rate systems. These data sets simulated spacecraft with numerous instrument data sources downlinking out-of-sequence and errored data streams. Simulated data streams were encapsulated in Consultative Committee for Space Data Systems (CCSDS) packet and NASCOM data formats. The knowledge and expertise gained in the development of the current simulation tools has been used to develop a new generation data simulation tool, known as the Simulated Telemetry Generation (STGEN) package. STGEN is a menu driven software package running on UNIX platforms that can implement dynamic test scenarios with very fast turn around times from the data set design to the data set generation. The error options and locations in the telemetry data stream are fed via simple programs which are in turn script-driven. Scripts are used to manipulate packets, frames, and permit error insertion more easily and quickly. This paper first describes the STGEN software package and its test data design strategies. It then provides an example of STGEN 's first usage in the testing of systems to support EOS-AM spacecraft. Finally, a description of future planned improvements and uses of STGEN are provided.
    • RADPAT: A NEW PORTABLE DIGITAL RADIATION PATTERN RECORDING SYSTEM

      Augustin, E. P.; Dunn, D. S.; Posada, J. F.; Sullivan, A.; Technical Systems Associates, Inc. (International Foundation for Telemetering, 1995-11)
      This paper describes a novel Radiating Antenna Digital Pattern Analysis Test system (RADPAT). The RADPAT system consists of a portable computer and a compact electronic module (EM) that interfaces to the antenna under test . The EM has standardized inputs and outputs that make it easy to adapt to any antenna or antenna system. In addition to functioning as a standard radiation pattern recorder, the RADPAT system can record conically scanning (CONSCAN), single channel monopulse, or sequential lobing patterns with only one sweep per axis . Since the radiation pattern is recorded digitally, it can automatically extract actual system data such as the error slope, crosstalk, 3 or 10 dB beamwidths, sidelobe levels, boresight shift, etc.. The briefcase size RADPAT system is portable, weighing only 18 lbs (8 kg). This can be a significant advantage for either verification of system parameters or for troubleshooting a component or system problem . Thus, the RADPAT system combined with a standard pattern receiver or a telemetry receiver can provide instantaneous, on-site evaluation of the radiation characteristics of an installed antenna system.
    • THE PHILLIPS LABORATORY’S MOBILE GROUND TRACKING STATION (MGTS)

      Stone, Christopher E.; Flint, Keith D.; Mathis, Gregory P.; Edwards Air Force Base (International Foundation for Telemetering, 1995-11)
      Phillips Laboratory's Space Experiments Directorate (PL/SX) is operating and upgrading the laboratory's premier transportable satellite tracking station, the Mobile Ground Tracking Station (MGTS) program. MGTS supports orbital, suborbital, and aircraft missions as a range system capable of processing and recording multiple data streams. MGTS receives, processes, displays, and records satellite state-of-health data, infrared images in a variety of wavelengths, video data, and state vector solutions based on IR returns from the Miniature Sensor Technology Integration (MSTI) satellite program. The program has began in 1990 under BMDO sponsorship, with the intent to supplement existing test ranges with more flexibility in range operations. Wyle Laboratories and Systems Engineering and Management Company (SEMCO) provided the technical expertise necessary to create the first MGTS system. Autonomy and off-road capability were critical design factors, since some of the operations envisioned require deployment to remote or hostile field locations. Since inception, MGTS has supported the Lightweight Exo-Atmospheric Projectile (LEAP) sub-orbital missions, the MSTI satellite program, and Air Force wargame demonstrations. In pursuit of these missions, MGTS has deployed to White Sands Missile Range (WSMR), NM; Air Force Flight Test Center (AFFTC), Edwards AFB, CA; Vandenberg AFB, CA; Falcon AFB, CO; and NASA's Wallops Island Flight Facility, VA, to receive critical mission telemetry data conforming to both IRIG and SGLS standards. This paper will describe the evolution of the MGTS program, current hardware configurations and past and future mission scenarios for the MGTS team.
    • A Low-Cost, Autonomous, Ground Station Operations Concept and Network Design for EUVE and Other Earth-Orbiting Satellites

      Abedini, A.; Moriarta, J.; Biroscak, D.; Losik, L.; Malina, R. F. (International Foundation for Telemetering, 1995-11)
      The Extreme Ultraviolet Explorer (EUVE) satellite was designed to operate with the Tracking and Data Relay Satellite System (TDRSS) and Deep Space Network (DSN). NASA, the Jet Propulsion Laboratory and the Center for EUV Astrophysics have been evaluating a commercially available ground station already used for NASA's Low Earth Orbit (LEO) weather satellites. This ground station will be used in a network of unattended, autonomous ground stations for telemetry reception, processing, and routing of data over a commercial, secure data line. Plans call for EUVE to be the initial network user. This network will be designed to support many TDRSS/DSN compatible missions. It will open an era of commercial, low-cost, autonomous ground station networks. The network will be capable of supporting current and future NASA scientific missions, and NASA's LEO and geostationary weather satellites. Additionally, it could support future, commercial communication satellites in low, and possibly medium, Earth orbit. The combination of an autonomous ground station and an autonomous telemetry monitoring system will allow reduction in personnel. The EUVE Science Operations Center has already reduced console work from three shifts to one by use of autonomous telemetry monitoring software.
    • AFFORDABLE GROUND STATION EQUIPMENT FOR COMMERCIAL AND SCIENTIFIC REMOTE SENSING APPLICATIONS

      Chesney, James R.; Bakos, Roger; TSI TelSys, Inc. (International Foundation for Telemetering, 1995-11)
      The remote sensing industry is experiencing an unprecedented rush of activity to deploy commercial and scientific satellites. NASA and its international partners are leading the scientific charge with The Earth Observation System (EOS) and the International Space Station Alpha (ISSA). Additionally, there are at least ten countries promoting scientific/commercial remote sensing satellite programs. Within the United States, commercial initiatives are being under taken by a number of companies including Computer Technology Associates, Inc., EarthWatch, Inc., Space Imaging, Inc., Orbital Imaging Corporation and TRW, Inc. This activity is due to factors including: technological advances which have lead to significant reductions in the costs to build and deploy satellites; an awareness of the importance of understanding human impact on the ecosystem; and a desire to collect and sell data some believe will be worth $1.5 billion (USD) per year within five years. The success and usefulness of these initiatives, both scientific and commercial, depends largely on the ease and cost of providing remotely sensed data to value added resellers and end-users. A number of these spacecraft will provide an interface directly to users. To provide these data to the largest possible user base, ground station equipment must be affordable and the data must be distributed in a timely manner (meaning seconds or minutes, not days) over commercial network and communications equipment. TSI TelSys, Inc. is developing ground station equipment that will perform both traditional telemetry processing and the bridging and routing functions required to seamlessly interface commercial local- and wide-area networks and satellite communication networks. These products are based on Very Large Scale Integration (VLSI) components and pipelined, multi-processing architectures. This paper describes TelSys’ product family and its envisioned use within a ground station.
    • Talking GPS Locating System

      Buchwitz, Guy R. (International Foundation for Telemetering, 1995-11)
      The Talking GPS Locating System (TGLS) was developed to facilitate recovery of airborne targets by vocalizing and transmitting their Global Positioning System (GPS) coordinates to surface recovery teams following target splashdown. The airborne portion of the TGLS includes an off-the-shelf five-channel GPS receiver board, a GPS antenna, a microcontroller board with voice sample/playback circuitry, and a transmitter with antenna. Also part of the TGLS is a Record/Test Unit (RTU) which is used for pre-launch voice recording and ground tests. Upon splashdown, the TGLS is energized, the GPS receiver is initialized, and an optional homing tone burst -- periodically interrupted by a voice message relaying target and GPS receiver status -- is transmitted. Once the receiver has output valid longitude and latitude information to the microcontroller, this position is vocalized as the GPS status portion of the broadcast message. Just one intelligible reception of this message by any inexpensive, properly-tuned voice receiver will allow recovery teams to vector to within 25 to 100 meters of the target regardless of weather conditions or the time of day.
    • ANALYSIS AND DESIGN OF CONFORMAL PRINTED ANTENNAS

      Hall, Richard C.; Wu, Doris I.; Boulder Microwave Technologies, Inc. (International Foundation for Telemetering, 1995-11)
      Conformal printed antennas of arbitrary shape are used for telemetry applications on high velocity vehicles due to their small size and light weight. The design of these antennas is difficult, however, since there are few accurate analytical models that take the effects of curvature into account. This paper discusses a computer aided design (CAD) tool for arbitrarily shaped printed antennas on cylindrical structures based on a rigorous analytical model. The tool is combined with a graphical user interface and can help antenna designers achieve close to optimal performance. An overview of the mathematical model is given here and the CAD tool is used to highlight the effects of curvature on printed antenna performance. Methods of obtaining circular polarization are reviewed.
    • Incorporation of Micro-Machined Sensor Technology for Increased Accuracy at Reduced Cost

      Cook, F. Paul; Aydin Vector Division (International Foundation for Telemetering, 1995-11)
      Benefiting from the Automotive world, Micro-Machined Sensor Technology moves into the Military arena with greater accuracy at a reduced price tag. Advances in Micro-Machining have produced silicone cantilever beam Sensors which meet or exceed some Military environmental specifications while providing a higher overall accuracy, compared to traditional cantilever beam designs. There are several companies such as Motorola, Analog Devices, Sensym, Silicone Designs, and NovaSensor to name a few who have established product lines in Accelerometers and Pressure Transducers. This paper describes an experience utilizing micro-technology Accelerometers which were designed to replace older technology sensors.