• FLIGHT SAFETY SYSTEM FOR UNMANNED AIRBORNE VEHICLES (UAVs)

      Pérez-Falcón, Tony; Kolar, Ray; Reliable System Services Corporation; Atlantic Coast Technologies, Inc. (International Foundation for Telemetering, 2002-10)
      This paper presents a Flight Safety System (FSS) for multiple, reliable Unmanned Air Vehicles (UAV’s) capable of flying Over-the-Horizon (OTH) and outside test range airspace. Expanded uses beyond flight safety, such as UAV Air Traffic Control, are considered also. This system satisfies the operational requirement for a Hazard Control Communication Channel as well as providing a reverse communications channel to provide Safety Critical Information to the Range Safety Officer (RSO). Upon examining 60 communications candidates, IRIDIUM accessed through a Data Distribution Network (DDN), with ARINC being a potential service provider, is recommended.
    • FLIGHT TERMINATION COMMAND AUTHENTICATION USING BLOCK ENCRYPTION

      Arce, Dennis; Bourne Technologies, Inc. (International Foundation for Telemetering, 2002-10)
      Next generation flight termination systems (FTSs) will use digital technologies to verify the authenticity of range safety commands by command receiver-decoders located on each vehicle. This paper will discuss the general principles behind simplex message authentication using a block encryption cipher, and presents examples for demonstration.
    • FPGAs: RE-INVENTING THE SIGNAL PROCESSOR

      Dick, Chris; Xilinx Inc. (International Foundation for Telemetering, 2002-10)
      FPGAs are increasingly being employed for building real-time signal processing systems. They have been used extensively for implementing the PHY in software radio architectures. This paper provides a technology and market perspective on the use FPGAs for signal processing and demonstrates FPGA DSP using an adaptive channel equalizer case study.
    • FQPSK-B Baseband Filter Alternatives

      Jefferis, Robert; TYBRIN Corporation (International Foundation for Telemetering, 2002-10)
      Designers of small airborne FQPSK-B (-B) transmitters face at least two significant challenges. First, many U.S. Department of Defense (DOD) test applications require that transmitters accommodate a continuum of data rates from 1, to at least 20 Mb/s in one design. Another challenge stems from the need to package a high-speed digital baseband signal generator in very close proximity to radio frequency (RF) circuitry required for 1.4 to 2.4 GHz operation. The -B baseband filter options prescribed by Digcom/Feher [2] are a major contributor to variable data rate design challenges. This paper summarizes a study of -B filter alternatives and introduces FQPSK-JR (JR), an alternative to -B that can simplify digital baseband transmitter designs. Very short impulse response digital filters are used to produce essentially the same spectral efficiency and nonlinear amplifier (NLA) compatibility as -B while preserving or improving detection efficiency (DE). In addition, a strategy for eliminating baseband shaping filters is briefly discussed. New signaling wavelets and, modified wavelet versus symbol sequence mapping rules associated with them, can be captured from a wide range of alternative filter designs.
    • A Fresh View of Digital Signal Processing for Software Defined Radios: Part I

      Harris, Fred; San Diego State University (International Foundation for Telemetering, 2002-10)
      Digital signal processing has inexorably been woven into the fabric of every function performed in a modern radio communication system. In the rush to the marketplace, we have fielded many DSP designs based on analog prototype solutions containing legacy compromises appropriate for the technology of a time past. As we design the next generation radio we pause to examine and review past solutions to past radio problems. In this review we discover a number of DSP design methods and perspectives that lead to cost and performance advantages for use in the next generation radio.
    • A Fresh View of Digital Signal Processing for Software Defined Radios: Part II

      Harris, Fred; San Diego State University (International Foundation for Telemetering, 2002-10)
      A DSP modem is often designed as a set of processing blocks that replace the corresponding blocks of an analog prototype. Such a design is sub-optimal, inheriting legacy compromises made in the analog design while discarding important design options unique to the DSP domain. In part I of this two part paper, we used multirate processing to transform a digital down converter from an emulation of the standard analog architecture to a DSP based solution that reversed the order of frequency selection, filtering, and resampling. We continue this tack of embedding traditional processing tasks into multirate DSP solutions that perform multiple simultaneous processing tasks.
    • Hardware Description for the Advanced Subminiature Telemetry System

      Sadowski, Eric M.; Schmidt, Robert; Cleveland Medical Devices Inc. (International Foundation for Telemetering, 2002-10)
      The Advanced Subminiature Telemetry System (ASMT) contract was awarded several years ago and the basic framework for the overall system has been described in earlier papers. This paper discusses an overview of the design of the hardware pieces to create the ASMT system.
    • HARDWARE SYSTEM DESIGN FOR VEHICLE NAVIGATOR

      Li, Chen; Qi-shan, Zhang; Beijing University of Aeronautics and Astronautics (International Foundation for Telemetering, 2002-10)
      This paper introduces the essential points for designing a navigating system, and describes the modules of a typical vehicle navigator. This paper also gives a practical navigator example. Some experience for design is also mentioned.
    • An IF Sampling Digital Receiver Implementation for Space-based Command and Telemetry Applications

      Maples, Bruce W.; Fix, Keith A.; CMC Electronics Cincinnati (International Foundation for Telemetering, 2002-10)
      This paper describes an approach to the implementation of an IF sampling digital receiver for low data rate command and telemetry applications in the NASA Goddard Spaceflight Tracking and Data Network (STDN) and Air Force Space-Ground Link System (SGLS). The digital design is targeted for an FPGA-based implementation and was written entirely in VHDL. Several size and clock reduction techniques are described which were utilized due to limited gate-array resources and power. The system-level design architecture is described followed by a discussion of algorithms and performance of critical stages in the receiver chain. Bit error performance of the prototype receiver is also presented. Finally, although this design is specifically targeted for a narrowband command and telemetry application, the methodology forms the basis of a configurable receiver for higher data rate applications.
    • IMPACT OF NETWORKED DATA ACQUISITION SYSTEMS ON TRANSDUCERS

      Eccles, Lee H.; Boeing Commercial Airplanes (International Foundation for Telemetering, 2002-10)
      Transducers have traditionally been incorporated into data systems by connecting the transducer to a signal conditioner that is then connected to a multiplexer with an Analog-to-Digital Converter (ADC). The signal conditioning, multiplexer and the ADC are usually included within the same assembly that is called a Data Acquisition Unit (DAU) or an encoder. A network centric data system allows the same architecture to be used if the interface to the encoder is changed to be a network interface. However, a network centric architecture allows other options as well. The signal conditioning and ADC can be included within the same package as the transducer and the assembly can be interfaced to the network. When this is combined with the processing capability now available, a whole new range of possibilities present themselves. The transducer can now be digitally processed to provide a linear output, it can be converted to Engineering Units, digitally filtered or have a host of other functions performed within the housing that contains the transducer. However, the network centric approach does not produce these advantages without some disadvantages. The major problem that needs to be solved is how we time stamp the data. With the encoder we could time stamp the PCM frame and be able to determine the time that a sample was taken from that information. Even in systems that convert the encoder to have a network interface, the time stamp needs to be affixed to the data in the encoder. With a network centric approach, the sample can be taken in the transducer and how to time stamp it becomes a real problem. This is a problem that must be considered at the system level. Some method of making time available at a low enough level in the system to allow transducer outputs to be time stamped is either a network issue or it requires a separate interface.
    • THE IMPACT OF NETWORKS ON THE RF LINK

      Brierley, Scott; Boeing Company (International Foundation for Telemetering, 2002-10)
      Using a network-based telemetry system places additional requirements on the Radio Frequency (RF) link. Limitations imposed by this link must be considered in advance when designing a network-based telemetry system.
    • The Impact Of Wireless Security Protocols on Post Processed Telemetry Data Transfer

      Kalibjian, Jeffrey R.; Hewlett Packard Corporation (International Foundation for Telemetering, 2002-10)
      Commercial wireless protocol use (e.g. Wireless Access Protocol, Bluetooth, etc.) is becoming widespread as the demand to access computing devices in remote locations grows. Although not widely prevalent today, wireless access of post processed telemetry data will become a common activity. Essential to the use of such a capability is the security of the wireless links involved in the data transfer. Each wireless protocol has an associated security paradigm. Some protocols have stronger security schemes than others and this should influence protocol selection for particular telemetry data transfer applications.
    • IMPLEMENTATION AND PERFORMANCE OF A HIGHSPEED, VHDL-BASED, MULTI-MODE ARTM DEMODULATOR

      Hill, Terrance; Geoghegan, Mark; Hutzel, Kevin; Nova Engineering Inc. (International Foundation for Telemetering, 2002-10)
      Legacy telemetry systems, although widely deployed, are being severely taxed to support the high data rate requirements of advanced aircraft and missile platforms. Increasing data rates, in conjunction with loss of spectrum have created a need to use available spectrum more efficiently. In response to this, new modulation techniques have been developed which offer more data capacity in the same operating bandwidth. Demodulation of these new waveforms is a computationally challenging task, especially at high data rates. This paper describes the design, implementation and performance of a high-speed, multi-mode demodulator for the Advanced Range Telemetry (ARTM) program which meets these challenges.
    • IN-SERVICE DETECTION OF MULTIPATH FADING

      Jefferis, Robert; TYBRIN Corporation (International Foundation for Telemetering, 2002-10)
      Multipath (MP) fading is the dominant channel impairment in many aeronautical telemetry links. One product of a recent multipath mitigation study is the discovery of a simple technique for detecting its presence over a useful range of conditions. The technique also detects significant random noise levels in the channel. This paper describes the “Signal Degradation Indicator” (SDI) and its application to FQPSK-B and SOQPSK [2] modulation. Laboratory emulation data is presented and implementation considerations are discussed.
    • International Telemetering Conference Proceedings, Volume 38 (2002)

      International Foundation for Telemetering, 2002-10
    • INTERNET TECHNOLOGY FOR FUTURE SPACE MISSIONS

      Rash, James; Hogie, Keith; Casasanta, Ralph; NASA; Computer Sciences Corporation (International Foundation for Telemetering, 2002-10)
      Ongoing work at National Aeronautics and Space Administration Goddard Space Flight Center (NASA/GSFC), seeks to apply standard Internet applications and protocols to meet the technology challenge of future satellite missions. Internet protocols and technologies are under study as a future means to provide seamless dynamic communication among heterogeneous instruments, spacecraft, ground stations, constellations of spacecraft, and science investigators. The primary objective is to design and demonstrate in the laboratory the automated end-to-end transport of files in a simulated dynamic space environment using off-the-shelf, low-cost, commodity-level standard applications and protocols. The demonstrated functions and capabilities will become increasingly significant in the years to come as both earth and space science missions fly more sensors and the present labor-intensive, mission-specific techniques for processing and routing data become prohibitively. This paper describes how an IP-based communication architecture can support all existing operations concepts and how it will enable some new and complex communication and science concepts. The authors identify specific end-to-end data flows from the instruments to the control centers and scientists, and then describe how each data flow can be supported using standard Internet protocols and applications. The scenarios include normal data downlink and command uplink as well as recovery scenarios for both onboard and ground failures. The scenarios are based on an Earth orbiting spacecraft with downlink data rates from 300 Kbps to 4 Mbps. Included examples are based on designs currently being investigated for potential use by the Global Precipitation Measurement (GPM) mission.
    • JAVA FOR REAL-TIME TELEMETRY SYSTEMS

      K/Bidy, Gilles; L-3 Communications (International Foundation for Telemetering, 2002-10)
      Because of an ever-increasing need for performance and high predictability in modern real-time telemetry systems, the Java programming language is typically not considered a viable option for embedded software development. Nevertheless, the Java platform provides many features that can easily be applied to embedded telemetry systems that other development platforms cannot match. But obviously, there are pitfalls to be aware of. This paper will present an alternative solution to address today’s problems in real-time telemetry systems and will cover the following topics: • Java development platforms for the embedded world • Impact on software portability and reusability • Performance and optimization techniques • Direct access to hardware devices • Memory management and garbage collection • Network-centric component-oriented architecture • Real-time examples from past experience • Future developments
    • LAUNCH VEHICLE EXHAUST PLASMA / PLUME EFFECTS ON GROUND TELEMETRY RECEPTION, QRLV-2

      McWhorter, Mark; Honeywell Aerospace Electronic Systems (International Foundation for Telemetering, 2002-10)
      This paper discusses the effect of vehicle exhaust plasma/plume on the ability to receive telemetered data via an S-band RF link. The data discussed herein was captured during the launch of the QRLV-2 (Quick Reaction Launch Vehicle) on April 24, 2002 from Kodiak Launch Center, Kodiak, Alaska using Honeywell’s BMRST (Ballistic Missile Range Safety Technology) system.
    • LEGACY SYSTEMS’ SENSORS BECOME PLUG-N-PLAY WITH IEEE P1451.3 TEDS

      Sinclair, Robert; Beech, Russell; Jones, Kevin; Mundon, Scott; Jones, Charles H.; NVE Corporation.; Edwards Air Force Base (International Foundation for Telemetering, 2002-10)
      Replacing and maintaining sensors in existing legacy systems is costly and time consuming since no information beyond voltage or current is supplied by these sensors. When a sensor is replaced or added, information for that sensor has to be incorporated by the software programmer into the main system software – a costly and time-consuming process. A method has been developed to give these old sensors the intelligence to meet the requirements of the proposed IEEE P1451.3 standard. This is accomplished with no changes to the legacy hardware and a minor, one time change to the legacy main system software.
    • LINEAR POWER AMPLIFIERS: A FINAL FRONTIER FOR SOFTWARE DEFINED RADIOS

      Andrews, M. S.; TRW Radio Systems (International Foundation for Telemetering, 2002-10)
      The scope of the problem with generalized linear power amplifiers is herein addressed. In this paper, after an introduction to the problem of linearity and power amplifiers is addressed, a survey of various design issues from PA topology, materials, and linearization electronics is given. Following this, a look toward future work in this very active area of current research is also offered.