• DOPPLER SHIFTED SPREAD SPECTRUM CARRIER RECOVERY USING REAL-TIME DSP TECHNIQUES

      De Leon, Phillip L.; Scaife, Bradley J.; New Mexico State University (International Foundation for Telemetering, 1998-10)
      In any satellite communication, the Doppler shift associated with the satellite’s position and velocity must be calculated in order to determine the carrier frequency. If the satellite state vector is unknown then some estimate must be formed of the Doppler-shifted carrier frequency. One elementary technique is to examine the signal spectrum and base the estimate on the dominant spectral component. If, however, the carrier is spread (as in most satellite communications) this technique may fail unless the chip rate-to-data rate ratio (processing gain) associated with the carrier is small. In this case, there may be enough spectral energy to allow peak detection against a noise background. In this paper, we present a method to estimate the frequency (without knowledge of the Doppler shift) of a spread-spectrum carrier assuming a small processing gain and binary-phase shift keying (BPSK) modulation. Our method relies on a simple, averaged discrete Fourier transform along with peak detection. We provide simulation results indicating the accuracy of this method. In addition, we will describe an all-digital hardware design based around a Motorola DSP56303 and high-speed A/D which implements this technique in real-time. The hardware design is to be used in NMSU’s implementation of NASA’s demand assignment, multiple access (DAMA) service.
    • MINIATURE PENETRATOR (MINPEN) ACCELERATION RECORDER DEVELOPMENT AND TEST

      Franco, R. J.; Platzbecker, M. R.; Sandia National Laboratories (International Foundation for Telemetering, 1998-10)
      The Telemetry Technology Development Department at Sandia National Laboratories actively develops and tests acceleration recorders for penetrating weapons. This new acceleration recorder (MinPen) utilizes a microprocessor-based architecture for operational flexibility while maintaining electronics and packaging techniques developed over years of penetrator testing. MinPen has been demonstrated to function in shock environments up to 20,000 Gs. The MinPen instrumentation development has resulted in a rugged, versatile, miniature acceleration recorder and is a valuable tool for penetrator testing in a wide range of applications.
    • Application of IP Multicasting to the NASA Communications Command and Telemetry Ground Network

      Spinolo, M. Chris; National Aeronautics and Space Administration (International Foundation for Telemetering, 1998-10)
      The NASA Communications (Nascom) Division has been directed to deploy Internet Protocol (IP) based technology for the ground segments of all present and future spaceflight telemetry networks. The Nascom network supports all NASA spaceflight telemetry, command and status requirements, from sounding rockets and balloons to the Hubble Space Telescope and the Space Shuttle. This paper discusses the challenges of transitioning a 35 year old, custom engineered, worldwide legacy telemetry network to IP, and the resulting, new NASA IP Operational Network for ground transport of spacecraft telemetry and command.
    • REDUCED APERTURE MICROSTRIP ANTENNAS FOR AIRBORNE VEHICLES

      Kujiraoka, Scott R.; De Vries, James M.; Naval Air Warfare Center (International Foundation for Telemetering, 1998-10)
      The available space for the mounting of antennas on missiles and airborne targets is very limited. The vehicle integrator is constantly striving for smaller antenna apertures while requiring increased performance. Microstrip antennas with moderate dielectric loading have been successfully utilized in the past to meet these requirements. With the advent of high dielectric substrate materials, the designer now has the option of further reducing the size of the antenna while preserving the most desirable performance attributes. An example of the size reduction achievable with the new substrate materials is presented along with performance characteristics.
    • ELIMINATION OF SIDELOBE RESPONSE

      Herold, F. W.; Kaiser, J. A.; Fredrick Herold & Associates, Inc. (International Foundation for Telemetering, 1998-10)
      Conventional phased arrays nominally sum the signals received by the elements prior to detection. By multiplying rather than summing signals received from pairs of elements, i.e., interferometer pairs, a set of Spatial Frequencies (SFs) is obtained. Obtaining the SFs requires employment of a multiple local oscillator technique. When summed, these spatial frequencies produce a single lobed (voltage) radiation pattern which, when passed through a biased detector, removes all sidelobes from the response at a small loss of desired signal power.
    • TELEMETERY DATA COLLECTION FROM OSCAR SATELLITES

      Haddock, Paul C.; New Mexico State University (International Foundation for Telemetering, 1998-10)
      This paper discusses the design, configuration, and operation of a satellite station built for the Center for Space Telemetering and Telecommunications Laboratory in the Klipsch School of Electrical and Computer Engineering Engineering at New Mexico State University (NMSU). This satellite station consists of a computer-controlled antenna tracking system, 2m/70cm transceiver, satellite tracking software, and a demodulator. The satellite station receives satellite telemetry, allows for voice communications, and will be used in future classes. Currently this satellite station is receiving telemetry from an amateur radio satellite, UoSAT-OSCAR-11. Amateur radio satellites are referred to as Orbiting Satellites Carrying Amateur Radio (OSCAR) satellites.
    • RADIO FREQUENCY PATH CHARACTERIZATION FOR WIDE BAND QUADRATURE AMPLITUDE MODULATION

      Bracht, Roger; Los Alamos National laboratory (International Foundation for Telemetering, 1998-10)
      Remote, high speed, high explosive wave front monitoring requires very high bandwidth telemetry to allow transmission of diagnostic data before the explosion destroys the sensor system itself. The main motivation for this study is that no known existing implementation of this sort has been applied to realistic weapons environments. These facts have prompted the research and gathering of data that can be used to extrapolate towards finding the best modulation method for this application. In addition to research of similar existing analysis and testing operations, data was recently captured from a Joint Test Assembly (JTA) Air Launched Cruise Missile (ALCM) flight.
    • High Rate Digital Demodulator ASIC

      Ghuman, Parminder; Sheikh, Salman; Koubek, Steve; Hoy, Scott; Gray, Andrew; National Aeronautics and Space Administration; Lockheed Martin Space Mission Systems & Services; SGT Inc. (International Foundation for Telemetering, 1998-10)
      The architecture of the High Rate (600 Mega-bits per second) Digital Demodulator (HRDD) ASIC capable of demodulating BPSK and QPSK modulated data is presented in this paper. The advantages of all-digital processing include increased flexibility and reliability with reduced reproduction costs. Conventional serial digital processing would require high processing rates necessitating a hardware implementation other than CMOS technology such as Gallium Arsenide (GaAs) which has high cost and power requirements. It is more desirable to use CMOS technology with its lower power requirements and higher gate density. However, digital demodulation of high data rates in CMOS requires parallel algorithms to process the sampled data at a rate lower than the data rate. The parallel processing algorithms described here were developed jointly by NASA’s Goddard Space Flight Center (GSFC) and the Jet Propulsion Laboratory (JPL). The resulting all-digital receiver has the capability to demodulate BPSK, QPSK, OQPSK, and DQPSK at data rates in excess of 300 Mega-bits per second (Mbps) per channel. This paper will provide an overview of the parallel architecture and features of the HRDR ASIC. In addition, this paper will provide an overview of the implementation of the hardware architectures used to create flexibility over conventional high rate analog or hybrid receivers. This flexibility includes a wide range of data rates, modulation schemes, and operating environments. In conclusion it will be shown how this high rate digital demodulator can be used with an off-the-shelf A/D and a flexible analog front end, both of which are numerically computer controlled, to produce a very flexible, low cost high rate digital receiver.
    • ISO 9001 Registration for the Electronic Hardware Fabrication Process at the Jet Propulsion Laboratory

      Bonner, J. K. “Kirk”; de Silveira, Carl; California Institute of Technology (International Foundation for Telemetering, 1998-10)
      More and more companies and organizations are recognizing the benefits to be gained by achieving ISO 9000 registration. An effort is underway at JPL to become ISO 9001 registered. To facilitate this activity, the entire laboratory has been divided into processes, each one having a designated process owner. This paper concentrates more specifically on one of these processes, namely, the Packaging and Fabrication of Electronic Hardware (PAFEH), and the effort being undertaken to ensure that this process will successfully pass registration. A comprehensive approach is being utilized by the Electronic Packaging and Fabrication Section to bring this about.
    • ALCATEL TELEMETRY TRANSMITTER AND BEACON TRANSMITTER (NEW GENERATION)

      Tonello, E.; Monica, G. Della; ALCATEL (International Foundation for Telemetering, 1998-10)
      Presentation for ITC 98 of Alcatel Espace last studies and developments regarding TTC Products This document lays on 3 parts: · a technical point of view · a technology/design description · a synthesis showing main performance and results
    • A DEVICE DRIVER ARCHITECTURE FOR TELEMETRY APPLICATIONS

      DiLemmo, Marc C.; Aydin Telemetry (International Foundation for Telemetering, 1998-10)
      This paper illustrates a device driver implementation used to support a PC compatible telemetry device. Device requirements included operation on Windows NT 4.0, Windows 95, Windows NT 5.0 and Windows 98 platforms. A single device driver was not possible due to the differences between driver requirements on the various operating systems. The Windows Driver Model (WDM) was considered for NT 5.0 and Win98, however, NT 4.0 and Win95 does not support the WDM. To minimize software development and support efforts, it was clear that an architecture compatible to both WDM, NT 4.0 and Windows 95 needed to be developed. The resulting layered device driver architecture provides a common upper interface and uses a register based model to describe the hardware at the lower interface. The common upper interface is compatible with all of the target operating systems and presents a consistent Applications Programming Interface (API) for the telemetry application developer. The lower interface is specific for each platform but contains minimal device specific functionality. A simple register I/O driver is easily implemented using all of the target operating systems. The layered architecture and register based interface to the hardware results in a multiple operating system code set which differs only at the lowest layer.
    • FQPSK-L: An Improved Constant Envelope Modulation Scheme for QPSK

      Lee, Tong-Fu; Wang, Shih-Ho; Liu, Chia-Liang; Bao, Liu; University of California Davis; Industrial Technology Research Institute; Tianjin University (International Foundation for Telemetering, 1998-10)
      A new constant envelope modulation scheme and architecture for QPSK by cubic spline interpolation methods which increase spectral efficiency and power efficiency, named FQPSK-L, is presented. This modulation technique is an extension of the Feher Quadrature Shift Keying (FQPSK) patented technologies, see Ref [1]. Being a constant envelope modulation, FQPSK-L can operate with class C power amplifier without spectrum regrowth. We achieve a more compact spectrum with comparable bit error rate performance. For example, FQPSK-L is about 20% more spectral efficient than GMSK BTb=0.3 from 40 to 70 dB attenuation point. Moreover, FQPSK-L intrinsically has spikes at fc ± 0.5fb, fc ± 1.0fb, fc ± 1.5fb, ... which are useful for carrier recovery, symbol time recovery and fading compensation. In Rayleigh fading channel, FQPSK-L outperform GMSK BTb=0.3 by 0.8 dB. FQPSK-L is an excellent scheme for wireless and satellite communications which require high spectral and power efficiency.
    • AN EFFICIENCY STUDY OF TELEMETRY DATA CYCLE MAPS

      Jones, Charles H.; Edwards Air Force Base (International Foundation for Telemetering, 1998-10)
      Data cycle maps (DCM) describe the cyclic mapping of telemetered data. The efficiency of a DCM thus directly effects the efficiency of the use of the telemetry spectrum. The availability of this spectrum is decreasing while the demand is increasing. Certainly one of the first things to be done in trying to alleviate this bandwidth crunch is to make sure that all bits in a telemetry stream are useful and required. This paper provides results of a study on what types of bits there are in a DCM and how the bits were allocated in DCMs actually used at Edwards AFB, California.
    • NEXT GENERATION DIGITAL BEAMFORMING ARRAY OPTIMIZED BY NEURAL NETWORK BEAMFORMING TECHNIQUES

      Sullivan, Arthur; Christodoulou, Christos; Chandler, Charles W. (International Foundation for Telemetering, 1998-10)
      The next generation Digital Beamforming Array (DBFA) requires techniques beyond the existing adaptive processing and optimization approaches. By utilizing neural network processing and genetic algorithms that mimic complicated natural processes, such as the brain and natural selection, new and superior Antenna Arrays can be designed. The use of Neural Networks and Genetic Algorithms combined with the existing techniques for DBFAs can yield the ultimate in “real-time,” “smart” antenna performance. Cost is significantly reduced by; allowing large manufacturing tolerances, the use of inexpensive components, and correcting by neural network techniques. This paper describes the technology and proposes a practical application of the technique to design a DBFA to track and transmit/receive telemetry from a shipboard vertically launched medium range missile.
    • TELEMETRY DESIGN FOR A BOBSLED ANALYSER

      Schooley, L.C.; Chyr, Y-H.; Jordan, M.; Hagedorn, M.; Han, B.; Pat, J.; Ting, S.; Trotman, T.; University of Canterbury (International Foundation for Telemetering, 1998-10)
      This paper was prepared as part of the team design competition for a graduate level course given at the University of Canterbury, in Christchurch, New Zealand. It presents a high level design of a bobsled data acquisition system which is intended to aid athletes and coaches in achieving the maximum benefit from their time at the bobsled track. The system will measure every applicable aspect of the bobsled’s performance down the track, and provide real time and near real time feedback for the athletes and the coach. This system implements an inertial navigation and position system, monitors wind speed, measures the drivers steering input and effort, measures individual pushing effort in the critical start stage of the run, and provides cue signals to the runners when to mount the sled. A robust packet format and error correction in conjunction with a E2ROM backup system ensure data integrity. The data is transmitted utilising a GMSK signalling scheme, operating at a frequency of 400MHz. A space conserving patch antenna is mounted on the bobsled and a leaky wave antenna placed alongside the track for the transmission system. A link budget and the error performance of the transmission system are analysed. A graphical front end at the coach’s base station provides real time data display and analysis.
    • Calendars and Current Calendar Issues: Year 2000 and GPS 1999 Week Number Roll Over

      Claflin, Ray, III; Claflin Associates (International Foundation for Telemetering, 1998-10)
      This paper will present a selected overview of calendars and calendar development from antiquity to the current Gregorian calendar. The current hot topics of the GPS 1999 Rollover and the Year 2000 Millennium Rollover will be explained.
    • TUNABLE FSK/AM SIGNAL DETECTOR ON A 6U-VME CARD

      Hordeski, Theodore J.,Jr.; GDP Space Systems (International Foundation for Telemetering, 1998-10)
      The telemetry and aerospace communities require communications equipment providing various modulation and demodulation formats. One format, with application in Space Ground Link Subsystems (SGLS), utilizes a Ternary (tri-tone) Frequency Shift-Keyed (FSK) signal Amplitude Modulated (AM) by a triangle waveform. Historically, SGLS equipment has operated with a fixed tri-tone frequency set (e.g., 65 kHz, 76 kHz and 95 kHz). The need for additional transmission channels and increased bandwidth efficiency creates the requirement for equipment with the flexibility to generate and receive varied and higher frequency tone sets. Combining analog and digital techniques, GDP Space Systems has developed the FDT001. It is an FSK/AM detector which recovers a bit rate clock at one of four selectable bit rates and reproduces ternary FSK modulation data over a widely tunable range of tone frequencies. The tuning range is expanded by using two methods of digital frequency discrimination. The following paper describes the design of the FDT001.
    • Accuracy of Computer Simulations that use Common Pseudo-random Number Generators

      Dusitsin, Krid; Kosbar, Kurt; University of Missouri – Rolla (International Foundation for Telemetering, 1998-10)
      In computer simulations of communication systems, linear congruential generators and shift registers are typically used to model noise and data sources. These generators are often assumed to be close to ideal (i.e. delta correlated), and an insignificant source of error in the simulation results. The samples generated by these algorithms have non-ideal autocorrelation functions, which may cause a non-uniform distribution in the data or noise signals. This error may cause the simulation bit-error-rate (BER) to be artificially high or low. In this paper, the problem is described through the use of confidence intervals. Tests are performed on several pseudo-random generators to access which ones are acceptable for computer simulation.
    • ACQUISITION STRATEGY ADAPTING TO TODAY’S TRENDS

      Colangelo, Ronald; Simulation, Training and Instrumentation Command (International Foundation for Telemetering, 1998-10)
      There is an acquisition management challenge to a program which has a limited market. One approach which can improve competition is the utilization of commercial technology. This utilization helps reduce unit cost and system obsolescence. The Hardened Subminiature Telemetry and Sensor System (HSTSS) has experienced the affects of a limited market and the need to utilize commercial technology. HSTSS plans to use partnering because the expertise is spread across the industry, and technology integration is required to fabricate an instrumentation system that would meet tri-service test requirements. There are many challenges facing the Program Manager; which create high program risk when proper acquisition procedures are not followed. HSTSS is this type of project. This paper will essentially discuss the acquisition strategy as it has evolved as well as the technical strategy. These strategies have been influenced by Government acquisition streamlining , available commercial technology and the programs limited production requirements. This is what the Government’s Project Managers are facing in these times of shrinking budgets and downsizing. The importance of the services working together, and sharing funds and technology to accomplish more with less is discussed in this paper. It is essential that government and industry work together as partners to reach the program’s goals. This paper proposes a program strategy based on our experience as to what is needed to incorporate partnering and commercial technology to successfully complete your program.
    • TCP/IP Remote Control of a Ground Station

      Massey, Dale P.; Universal Space Network, Inc. (International Foundation for Telemetering, 1998-10)
      Satellite tracking ground stations are under continuous pressure to automate. Autonomy is generally the desired goal, but if the ground stations are in a Commercial Ground Network(CGN) setup to support many missions simultaneously, remote control of such stations is of much more importance. The proliferation of Low Earth Orbiting (LEO) science, earth resources and eventually global communications satellites either in orbit or planned, requires a much lower cost methodology for ground support. A CGN of TCP/IP remotely controlled ground stations lowers much of the manpower that was historically required to operate such stations. This paper will cover the remote control aspects needed for a satellite ground tracking station and offer a unique remote control topology utilizing TCP/IP.