• THE APPLICATION OF DISK RECORDING TECHNOLOGY TO PLATFORM DATA CAPTURE & ANALYSIS

      Howard, John M.; Avalon Electronics Ltd (International Foundation for Telemetering, 2003-10)
      Disk Recorders now represent a high performance, low cost and reliable alternative to traditional tape recorders for a wide range of platform data recording applications. This paper discusses the latest advances in disk-based recording technology in the context of multi-channel Telemetry applications, showing the degree of flexibility that is now possible in terms of both channel count and the ability to record synchronous and asynchronous digital data streams alongside multiple wideband analog channels. The techniques described are equally applicable to Acoustic, SIGINT and Telecommunications data capture and analysis applications aboard static, airborne and maritime platforms. Topics covered include how new disk-based data capture technologies have been able to extend bandwidth, storage capacity, signal fidelity and the overall capability of mission recorders. Advanced operational issues, including true ‘read-after-write’, data security, portability and archiving, enhanced data management and analysis strategies are also covered. The Paper includes detailed test results from COTS Disk Recorders already in service as well as an informative Road Map for this exciting new technology.
    • INTEGRATED NETWORK-ENHANCED TELEMETRY

      Skelley, Dan S.; Naval Air Warfare Center (International Foundation for Telemetering, 2003-10)
      The integrated Network-Enhanced Telemetry (iNET) study is a unique effort that will, for the first time in fifty years, redefine the basic test and evaluation telemetry infrastructure used at every DoD major range and test facility base (MRTFB). Sponsored by OSD/DOT&E, the iNET study is a single-year effort in progress dedicated to identifying end-user needs, developing an experimental network-enhanced architecture, documenting technology gaps, and reporting on the overall feasibility of implementing and deploying telemetry network(s) at the MRTFBs. Using organizational approaches similar to that used to manage the Internet, the vision is to establish and iterate an experimental architecture toward mature and stable standards that accommodate the needs of the broadest possible user base. The Integrated Network Enhanced Telemetry (iNET) study will produce a needs discernment document, telemetry network architecture document, technology shortfalls document, and feasibility report that addresses the ability of a telemetry network system to enhance current pointto- point telemetry systems to meet the future needs of the Major Range Test Facility Base (MRTFB). The conclusions of the feasibility report will be backed up with an extensive analysis of the future needs of the MRTFBs, a draft telemetry network architecture that meets these needs, and analysis of the technical challenges of implementing the system. The scope of this study include s the on-vehicle data acquisition network, the RF network, and the interface to the data management and archival system. This forum will present an overview of the study efforts and viewpoints to date, followed by an interactive panel discussion.
    • TELEMETRY DATA DISTRIBUTION UTILIZING A MULTICAST IP NETWORK

      DeLong, Brian; Sypris Data Systems (International Foundation for Telemetering, 2003-10)
      The efficient distribution of telemetry data via standard Ethernet networks has become an increasingly important part of telemetry system designs. While there are several methods and architectures to choose from, a solution based on IP multicast transmission provides for a fast and efficient method of distributing data from a single source to multiple clients. This data distribution method allows for increased scalability as data servers are no longer required to service individual client connections, and network bandwidth is minimized with multiple network clients being simultaneously serviced via a single data transmission.
    • WINGS NETWORK ARCHITECTURE FOR THE MISSION SEGMENT DATA DISTRIBUTION

      Downing, Bob; Harris, Jim; Coggins, Greg; James, Russell W.; Arcata Associates, Incorporated; National Aeronautical Space Adminstration; James Bros. Systems, Inc. (International Foundation for Telemetering, 2003-10)
      The Western Aeronautical Test Range (WATR) Integrated Next Generation System (WINGS) Mission Segment provides data acquisition, processing, display and storage in support of each project’s mission at NASA Dryden Flight Research Center (DFRC). The network architecture for WINGS Mission Segment is responsible for distributing a variety of information from the Telemetry and Radar Acquisition and Processing System (TRAPS), which is responsible for data acquisition and processing, to the Mission Control Centers (MCCs) for display of data to the user. WINGS consists of three TRAPS and four MCCs, where any TRAPS can drive any one or multiple MCCs. This paper will address the requirements for the TRAPS/MCC network and the design solution.
    • A DYNAMIC MULTI-PROTOCOL INTERFACE FOR TT&C SATELLITE BASEBAND PROCESSOR

      Mitchell, Marcella B.; Thomas, Alain; Enertec America, Inc.; Enertec SA (International Foundation for Telemetering, 2003-10)
      This paper presents the architecture of a new dynamic multi-protocol network interface implemented on a TT&C satellite baseband processor. Today Ethernet is the main connection of the equipment in a satellite system. Various protocols are necessary to optimize support of data exchange and are implemented using several supports such as Serial lines, Ethernet or Internet. The capability to dynamically switch from one service to another, using the most adapted interface, is the key factor for a multi-mission, multi-satellite system.
    • THE CASE FOR MIS-MATCHED FILTERING IN NONLINEARLY AMPLIFIED FQPSK AND GSM INTER-OPERABLE SYSTEMS

      Gonzalez, Maria C.; University of California, Davis (International Foundation for Telemetering, 2003-10)
      Structures for power-efficient systems, requiring the use of non-linear amplifiers and thus Mis-Matched filtering, are presented. These architectures allow for changeable amounts of power, bit rate, and modem selectable formats. The benefits include power/spectral efficiency, in addition to robust operation in mobile environments . Alternatives to matched filter receivers are addressed for power constrained systems associated with mobile systems in frequency selective channel environments. Two types of modulation format FQPSK[1][2][3] and GMSK[4], with different mismatch filters at the receiver, are analyzed.
    • AN EXTENSION OF SOQPSK TO M-ARY SIGNALLING

      Bishop, Chris; Fahey, Mike; Phase IV Systems, Inc. (International Foundation for Telemetering, 2003-10)
      Shaped Offset Quadrature Phase Shift Keying (SOQPSK) has the advantages of low sidelobes and high detection probability; however, its main lobe has a fixed width set by the number of constellation points. By slightly modifying the modulation scheme, the four constellation points of quadrature shift keying can be changed to M constellation points where M is a power of 2. After this change, the power spectral density (PSD) retains low sidelobes, and the desirable property of being able to detect the signal by integrating over two symbol periods is retained.
    • SELECTABLE PERMUTATION ENCODER/DECODER FOR A QPSK MODEM

      Weitzman, Jonathan M.; GDP Space Systems (International Foundation for Telemetering, 2003-10)
      An artifact of QPSK modems is ambiguity of the recovered data. There are four variations of the output data for a given input data stream. All are equally probable. To resolve this ambiguity, the QPSK data streams can be differentially encoded before modulation and differentially decoded after demodulation. The encoder maps each input data pair to a phase angle change of the QPSK carrier. In the demodulator, the inverse is performed - each phase change of the input QPSK carrier is mapped to an output data pair. This paper discusses a very simple and unique differential encoder/decoder that handles all possible data pair/phase change permutations.
    • MULTI-SYMBOL NONCOHERENT DETECTION OF MULTI-H CPM

      Rice, Michael; Perrins, Erik; Brigham Young University (International Foundation for Telemetering, 2003-10)
      Two receivers are presented for the general case of noncoherent detection of multi-h continuous phase modulation (CPM). Both receivers yield performance gains using multi-symbol observations. The first is an existing receiver [1, 2] which has previously been applied to PCM/FM [3] and is now applied to the ARTM Tier II telemetry waveform. The second receiver is presented for the first time in this paper. The existing noncoherent receiver is found to perform poorly (and with high complexity) for the ARTM Tier II case. For single-symbol observations, the new receiver outperforms conventional FMdemodulation for both telemetry waveforms, and for multi-symbol observation lengths its performance approaches that of the optimal coherent receiver. The performance is evaluated using computer simulations. Receiver performance is also evaluated using a simple channel model with varying carrier phase. The traditional FM demodulator approach is found to outperform both receivers as channel conditions worsen.
    • EXPERIMENTAL RESULTS FOR PCM/FM, TIER 1 SOQPSK, AND TIER II MULTI-H CPM WITH TURBO PRODUCT CODES

      Geoghegan, Mark; Nova Engineering Inc. (International Foundation for Telemetering, 2003-10)
      Improving the spectral-efficiency of aeronautical telemetry has been a principal area of research over the last several years due to the increasing demand for more data and the limitation of available spectrum. These efforts have lead to the development of the ARTM Tier 1 SOQPSK and Tier II Multi-h CPM waveforms which improve the spectral efficiency by two and three times, as compared to legacy PCM/FM, while maintaining similar detection efficiency. Now that more spectrally efficient waveform options are becoming available, another challenge is to further increase the detection performance. Better detection efficiency translates into additional link margin that can be used to extend the operating range, support higher data throughput, or significantly improve the quality of the received data. It is well known that Forward Error Correction (FEC) is one means of achieving this objective at the cost of additional overhead and increased receiver complexity. However, as mentioned above, spectral efficiency is also vitally important meaning that the FEC must also have a low amount of overhead. Unfortunately, low overhead and high coding gain are generally conflicting trades, although recent work has shown that Turbo Product Codes (TPC) are a particularly attractive candidate. Computer simulations predict that very impressive gains in detection performance are possible for a relatively small increase in bandwidth. The main drawbacks are the additional complexity of the decoding circuitry and an increase in receive side latency. This paper presents the latest simulation and hardware performance results of PCM/FM, SOQPSK, and Multi-h CPM with TPC.
    • EXPERIMENTAL RESULTS FOR PCM/FM, TIER 1 SOQPSK, AND TIER II MULTI-H CPM WITH CMA EQUALIZATION

      Geoghegan, Mark; Nova Engineering Inc. (International Foundation for Telemetering, 2003-10)
      It is widely recognized that telemetry channels, particularly airborne channels, are afflicted by multipath propagation effects. It has also been shown that adaptive equalization can be highly effective in mitigating these effects. However, numerous other factors influence the behavior of adaptive equalization, and the type of modulation employed is certainly one of these factors. This is particularly true on modulations that exhibit different operating bandwidths. Computer simulations using the Constant Modulus Algorithm (CMA) have recently been reported for PCM/FM, ARTM Tier 1 SOQPSK, and Tier II SOQPSK. These encouraging results have led to a hardware implementation of a CMA equalizer. This paper presents the latest results from this work.
    • FREQUENCY CALIBRATION FOR THE TRANSMISSION SYSTEM OF QUARTZ CRYSTAL MEASUREMENT USING GPS

      Jun, Yang; Qishan, Zhang; Jinpei, Wu; Beihang University (International Foundation for Telemetering, 2003-10)
      Quartz crystal is an important electronic element in the field of communication systems, computer systems, etc. It is important to precisely measure the frequency of quartz crystal unit for manufacturing. The Pi-network transmission system recommended by International Electrotechnical Commission (IEC) is generally acknowledged as a measurement technique. However it needs a precise frequency source. The frequency source must be calibrated within a regular period in the process of manufacturing. Frequency counters, time internal counters, phase comparisons, which are the most common frequency calibrations, are introduced in the paper. Nowadays GPS has also become the primary system for frequency calibration. GPS receivers provide 1 PPS (Pulse Per Second) with accuracy < 100 nanoseconds to UTC under normal conditions. Motorola UT Oncore timing GPS with time accuracy < 50ns (1 sigma) uses time RAIM algorithm to ensure the validity and reliability of measurements. The comparison between the precise 1PPS and local reference is implemented. And the phase differences are logged and read by computer. According to the values, the frequency output of DDS is coordinated. In order to reduce the phase ambiguity, local reference is divided before comparison. The calibration can be implemented at any time by GPS. Block diagrams of calibration are presented in this paper.
    • TEST AND EVALUATION OF GPS/DR APPLICATION FOR CAR NAVIGATION SYSTEM

      Dongkai, Yang; Yanhong, Kou; Zhi, Chen; Qishan, Zhang; Aigong, Xu; BeiHang University; Nanyang Technological University (International Foundation for Telemetering, 2003-10)
      Global Positioning System (GPS) was analyzed in terms of its repeatable accuracy, UTM projection for 2D plane coordinate system, satellite visibility performance and the horizontal dilution of positioning (HDOP). The principle of Dead Reckoning together with body coordinate system transformation was introduced. The complementary performance of GPS and DR, and GPS/DR integration using gyroscope and accelerometer were given. Test results were demonstrated that the repeatable accuracy of GPS alone is about 10 meters in open air, and DR can provide continuous positioning output within sufficient accuracy when GPS signal is outage.
    • THE SPREAD-SPECTRUM MULTIPLEXING TELEMETRY SYSTEM USING PARALLEL MOVE EQUIVALENT SEQUENCE

      Wang, Yongjian; Zhao, Honglin; Zhou, Tingxian; Harbin Institute of Technology (International Foundation for Telemetering, 2003-10)
      In this paper, based on the parallel move equivalent sequence of m sequence ,one type of CDM telemetry system is issued. Also the method for anti multi-path interference(MPI) of the system is proposed and its performance is analyzed. We proved that this system not only holds the merits which are inherent in common spread-spectrum communication system, but also has better transmission efficiency.
    • TEMPORAL ALIGNMENT OF TELEMETRY STREAMS WITH DIVERSE DELAY CHARACTERISTICS

      Kovach, Bob; Terawave Communications (International Foundation for Telemetering, 2003-10)
      In many test ranges, it is often required to acquire a number of telemetry streams and to process the data simultaneously. Frequently, the streams have different delay characteristics, requiring temporal alignment before the processing step. It is desired to have the capability to align these streams so that the events in each stream are coincident in time. Terawave Communications has developed technology to perform temporal alignment for a number of streams automatically. Additionally, the algorithm performs the delay compensation independent of the source data rate of each stream. Terawave will present the algorithm and share the results of their testing in a test installation.
    • The Realization Analysis of SAR Raw Data With Block Adaptive Vector Quantization Algorithm

      Yang, Yun-zhi; Huang, Shun-ji; Wang, Jian-guo; University of Electronic Science and Technology of China (International Foundation for Telemetering, 2003-10)
      In this paper, we discuss a Block Adaptive Vector Quantization(BAVQ) Algorithm for Synthetic Aperture Radar(SAR). And we discuss a realization method of BAVQ algorithm for SAR raw data compressing in digital signal processor. Using the algorithm and the digital signal processor, we have compressed the SIR_C/X_SAR data.
    • ADAPTIVE SIGNAL DEGRADATION INDICATION (SDI) FOR DIVERSITY BRANCH SELECTION (DBS)

      Laird, Daniel T.; 412TW/ENTI(ARTM) (International Foundation for Telemetering, 2003-10)
      One of several methods currently under investigation to increase telemetry efficiency is channel diversity selection. A spatial technique we are exploring exploits a signal quality indicator of phase demodulation to select ‘competing’ telemetry channels sourced by antenna separated by fractional wavelengths. The Advanced Range Telemetry (ARTM) program, a Centralized Test and Evaluation Improvement Program (CTEIP) research project funded by the Office of the Secretary of Defense (OSD), recently investigated three switching criteria for a multiple antenna system. This paper will discuss an algorithm that controls channel selection, or diversity branch selection (DBS), using a combination of the techniques investigated.
    • A Bit Error Rate Analysis of Offset QPSK over the Aeronautical Telemetry Multipath Channel

      Rice, Michael; Dang, Xiaoyu; Brigham Young University (International Foundation for Telemetering, 2003-10)
      The impact of multipath fading parameters on the probability of error for Offset QPSK (OQPSK) is derived. The multipath fading channel is modeled using the aeronautical telemetry channel model [1-2]. Expressions for the probability of bit error are derived that are a function of the multipath model parameters. The expressions are shown to agree with computer simulations and show that a strong multipath reflection with a short delay causes much more degradation than a weak multipath reflection with a long delay.
    • A DIGITAL INTEGRATOR FOR AN S-BAND HIGH-SPEED FREQUENCY-HOPPING PHASE-LOCKED LOOP

      Holtzman, Melinda; Johnson, Bruce; Lautzenhiser, Lloyd; University of Nevada; Emhiser Research, Incorporated (International Foundation for Telemetering, 2003-10)
      Phase-locked loop (PLL) frequency synthesizers used for high-speed data transmission must rapidly hop and lock to new frequencies. The fundamental problem is that the settling time depends inversely on the loop bandwidth, and increasing the bandwidth causes unwanted noise interference and stability problems for the circuit. We demonstrate the feasibility of replacing the analog integrator in the PLL with a digital integrator. This circuit has advantages of increased hopping speed, ability to compensate for temperature drift and system stability. PLL lock-in was demonstrated in a prototype circuit designed and built with both discrete components and with a programmable logic device.
    • SATELLITE GROUND STATION SECURITY USING SSH TUNNELING

      Horan, Stephen; Mauldin, Kendall; New Mexico State University (International Foundation for Telemetering, 2003-10)
      As more satellite ground station systems use the Internet as a means of connectivity, the security of the ground stations and data transferred between stations becomes a growing concern. Possible solutions include software-level password authentication, link encryption, IP filtering, and several others. Many of these methods are being implemented in many different applications. SSH (Secure Shell) tunneling is one specific method that ensures a highly encrypted data link between computers on the Internet. It is used every day by individuals and organizations that want to ensure the security of the data they are transferring over the Internet. This paper describes the security requirements of a specific example of a ground station network, how SSH can be implemented into the existing system, software configuration, and operational testing of the revised ground network.