• INTERFERENCE REJECTION PERFORMANCE AS A MEANS OF FREQUENCY OPTIMISATION IN A MIXED CELLULAR/MANET NETWORK

      Dean, Richard; Webley, Kayonne; Morgan State University (International Foundation for Telemetering, 2006-10)
      Research at Morgan State University shows a means of enabling both a mobile ad-hoc network (MANET) and a cellular network to operate simultaneously in the same spectrum. This enhanced frequency efficiency would facilitate the creation of a hybrid or Mixed Cellular/MANET network (MCMN) in which each of the MCMN sub-networks would have access to the entire allotted spectrum. Interference rejection and excision have been identified as a means of distinguishing between and isolating the two different kinds of signals. This paper shows the promising performance of such techniques within the MCMN environment as a part of the integrated Network Enhanced Telemetry (iNET) project.
    • EVERYTHING YOU WANTED TO KNOW ABOUT DOUBLE DIFFERENTIAL ENCODERS BUT WERE AFRAID TO ASK

      Perrins, Erik; University of Kansas (International Foundation for Telemetering, 2006-10)
      The existing offset quadrature phase shift keying (OQPSK) differential encoder in IRIG-106 is a curious scheme with a rather mysterious origin. In this paper, an alternative scheme known as double differential encoding is proposed. In many aspects, the proposed scheme has equivalent performance to the existing scheme: it successfully resolves the 4-phase ambiguity introduced by most carrier phase tracking loops and it also produces two decoded bit errors for each detection error. However, the proposed scheme has a number of conceptual advantages: it can be derived easily from first principles, it decouples the operations of even-bit/odd-bit demultiplexing and differential encoding, and it greatly simplifies the overly-complicated binary-to-ternary symbol mapping for OQPSK. It is also demonstrated to have tangible benefits, such as improved performance in systems with error control coding.
    • REDUCED COMPLEXITY TRELLIS DETECTION OF SOQPSK-TG

      Rice, Michael; Nelson, Tom; Brigham Young University (International Foundation for Telemetering, 2006-10)
      The optimum detector for shaped offset QPSK (SOQPSK) is a trellis detector which has high complexity (as measured by the number of detection filters and trellis states) due to the memory inherent in this modulation. In this paper we exploit the cross-correlated, trellis-coded, quadrature modulation (XTCQM) representation of SOQPSK-TG to formulate a reduced complexity detector. We show that a factor of 128 reduction in the number of trellis states of the detector can be achieved with a loss of only 0.2 dB in bit error rate performance as compared to optimum at P(b) = 10^(-5).
    • An approach to Integrated Spectrum Efficient Network Enhanced Telemetry (iSENET)

      Okino, Clayton; Gao, Jay; Clare, Loren; Darden, Scott; Walsh, William; Loh, Kok-kiong; Jet Propulsion Laboratory; LinQuest Corporation (International Foundation for Telemetering, 2006-10)
      As the integrated Network Enhanced Telemetry (iNET) program moves forward in resolving systems engineering design and architecture definition, critical technology “gaps” and a migration path to realizing the integration of this technology are needed to insure a smooth transition from the current legacy point to point telemetry links to a network oriented telemetry system. Specifically identified by the DoD aeronautical telemetry community is the need for a migration to a network solution for command, control, and transfer of test data by optimizing the physical, data link, and network layers. In this paper, we present a network centric telemetry preliminary architecture approach based on variants of 802.11 that leverages the open standards as well as the previous Advanced Range Telemetry (ARTM) work on the physical layer waveform. We present a burst modem approach based on the recent AOFDM 802.11a work, a TDMA-like MAC layer based on 802.11e, and then add additional MAC layer features to allow for the multi-hop aeronautical environment using a variant of the current working standard of 802.11s. The combined benefits of the variants obtained from 802.11a, 802.11e, and 802.11s address the needs for both spectrum efficiency in the aeronautical environment and the iNET program.
    • SIMULATION OF THE AERONAUTICAL RADIO CHANNEL FOR TELEMETRY APPLICATIONS

      Dean, Richard; Mwangi, Patricia A. W.; Haj-Omar, Amr; Montaque, Kishan; Morgan State University (International Foundation for Telemetering, 2006-10)
      The aeronautical channel is an air to ground channel characterized by multipath, high doppler shifts, Rayleigh fading and noise. Use of a channel sounder ensures proper estimation of the parameters associated with the impulse response of the channel. These estimates help us to characterize the radio channels associated with aeronautical telemetry. In order to have a satisfactory channel characterization, the amplitudes, phase shifts and delays associated with each multipath component in the channel model must be determined.
    • CHAPTER 10 RECORDING STANDARD UPDATE

      Lockard, Michael T.; Garling, James A. Jr; EMC Corporation, Solutions Engineering Group (International Foundation for Telemetering, 2006-10)
      The IRIG 106 Chapter 10 Standard has evolved significantly since its inception. This paper covers the background, technology, status, users, supporting vendors and future considerations such as ground-based recording and archiving. Also covered are samples of toolsets available for troubleshooting, validation, data processing and display of Chapter 10 data
    • MANAGING MULTI-VENDOR INSTRUMENTATION SYSTEMS WITH ABSTRACTION MODELS

      Lockard, Michael T.; Garling, James A. Jr; EMC Corporation, Solutions Engineering Group (International Foundation for Telemetering, 2006-10)
      The quantity and types of measurements and measurement instrumentation required for a test are growing. This paper describes a methodology to define and program multi-vendor instrumentation using abstraction models in a database that allows new instrumentation to be defined rapidly. This allows users to support multiple vendors’ systems while using a common user interface to define instrumentation networks, bus catalogs, measurements, pulse code modulated (PCM) formats, and data processing requirements.
    • AN IP-BASED RECORDING SYSTEM

      Roach, John; Hildin, John; Teletronics Technology Corporation (International Foundation for Telemetering, 2006-10)
      Traditionally, acquired instrumentation data on a non-destructive test article is recorded to a nonvolatile memory recorder. The data acquisition system usually samples and formats its inputs before transmitting the data to the recorder (also known in this paper as a data sink) via a PCM serial data stream (i.e., clock and data). In a network-based data acquisition architecture, the inclusion of an IP-based recorder adds a new dimension to the data acquisition process. Any IP network inherently allows for the bi-directional exchange of data. In this environment, the IPbased recorder can be treated as both a data sink for parameter recording and a data source for parameter extraction, data rate statistics, and recorder status reporting. The network model recasts the data recorder’s function as a file server to which multiple clients could be simultaneously requesting services. Those clients that represent the data acquisition nodes are requesting storage of their acquired parameters. Clients, such as transmitters or test engineers, are requesting access to archived data or status information for further processing. This paper presents the advantages of using an IP-based recorder in a network-based data acquisition system. The availability of an IP interface along with the intelligence built into the recorder expands its capabilities beyond that of a conventional PCM recorder. These capabilities include real-time health monitoring, support for the Simple Network Management Protocol (SNMP), data mining, reporting of real-time performance and network statistics.
    • AIRBORNE NETWORK SWITCH WITH IEEE-1588 SUPPORT

      Hildin, John; Arias, Sergio; Teletronics Technology Corporation (International Foundation for Telemetering, 2006-10)
      Today’s data acquisition systems are typically comprised of data collectors connected to multiplexers via serial, point-to-point links. Data flows upstream from the sensors or avionics buses to the data acquisition units, to the multiplexer and finally to the recorder or telemetry transmitter. In a networked data acquisition system, data is transported through the network “cloud”. At the core of the network “cloud” is the network switch. The switch is responsible for distributing and directing data within the network. Network switches are commonplace in the commercial realm. Many businesses today could not function without them. A network-based data acquisition system, however, places additional burdens on the network switch. As in a commercial network, the switch in a data acquisition system must be able to distribute data packets within the network. In addition, it must be able to perform in a harsh environment, occupy a minimal amount of space, operate with limited or no external cooling, be configurable, and deal with the distribution of time information. This paper describes the required features of a ruggedized network switch and the implementation challenges facing its design. As a core component of a network-based data acquisition system, an ideal switch must be capable of operating in a large number of configurations, transporting and aggregating data between data sources and data sinks, with a mixture of devices operating at rates ranging from a few thousand bits per second to several gigabits per second, over twisted pair or fiber optic links. To ensure time coherency, the switch must also facilitate a time distribution mechanism, e.g., IEEE-1588 Precision Time Protocol (PTP). The gigabit switch described here uses the PTP to implement an end-to-end clock synchronization, for distributed acquisition nodes, to within 300 nanoseconds.
    • LAUNCH VEHICLE EXHAUST PLASMA / PLUME EFFECTS ON GROUND TELEMETRY RECEPTION, STARS FT-04-1

      McWhorter, Mark; Honeywell Aerospace Electronic Systems (International Foundation for Telemetering, 2006-10)
      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 presented herein were captured during the launch of the STARS FT-04-1 on February 23, 2006 from Kodiak Launch Center, Kodiak, Alaska using Alaska Aerospace Development Corporation’s (AADC) Range Safety and Telemetry System (RSTS), designed and integrated by Honeywell.
    • AN ADAPTIVE BASEBAND EQUALIZER FOR HIGH DATA RATE BANDLIMITED CHANNELS

      Wickert, Mark; Samad, Shaheen; Butler, Bryan; University of Colorado at Colorado Springs; Real-Time Logic Inc. (International Foundation for Telemetering, 2006-10)
      Many satellite payloads require wide-band channels for transmission of large amounts of data to users on the ground. These channels typically have substantial distortions, including bandlimiting distortions and high power amplifier (HPA) nonlinearities that cause substantial degradation of bit error rate performance compared to additive white Gaussian noise (AWGN) scenarios. An adaptive equalization algorithm has been selected as the solution to improving bit error rate performance in the presence of these channel distortions. This paper describes the design and implementation of an adaptive baseband equalizer (ABBE) utilizing the latest FPGA technology. Implementation of the design was arrived at by first constructing a high fidelity channel simulation model, which incorporates worst-case signal impairments over the entire data link. All of the modem digital signal processing functions, including multirate carrier and symbol synchronization, are modeled, in addition to the adaptive complex baseband equalizer. Different feedback and feed-forward tap combinations are considered as part of the design optimization.
    • COMMUNICATIONS OVER AIRCRAFT POWER LINES: A PRACTICAL IMPLEMENTATION

      Tian, Hai; Trojak, Tom; Jones, Charles H.; Teletronics Technology Corporation; Edwards Air Force Base (International Foundation for Telemetering, 2006-10)
      This paper presents a practical implementation of a hardware design for transmission of data over aircraft power lines. The intent of such hardware is to significantly reduce the wiring in the aircraft instrumentation system. The potential usages of this technology include pulse code modulation (PCM), Ethernet and other forms data communications. Details of the fieldprogrammable gate array (FPGA) and printed circuit board (PCB) designs of the digital and analog front end will be discussed. The power line is not designed for data transmission. It contains considerable noise, multipath effects, and time varying impedance. Spectral analysis data of an aircraft is presented to indicate the difficulty of the problem at hand. A robust modulation is required to overcome the harsh environment and to provide reliable transmission. Orthogonal frequency division multiplexing (OFDM) has been used in power line communication industry with a great deal of success. OFDM has been deemed the most appropriate technology for high-speed data transmission on aircraft power lines. Additionally, forward error correction (FEC) techniques are discussed.
    • DESIGN AND EXPERIMENTATION WITH A SOFTWARE-DEFINED ACOUSTIC TELEMETRY MODEM

      Doonan, Daniel; Fu, Tricia; Utley, Chris; Iltis, Ronald; Kastner, Ryan; Lee, Hua; University of California, Santa Barbara (International Foundation for Telemetering, 2006-10)
      This paper describes the design and successful development of an acoustic modem for potential use in underwater ecological sensor networks. The presentation includes theoretical study, design and development of both software and hardware, laboratory experiments, full-scale field tests, and the documentation and analysis of field-test results.
    • LEVERAGING INTERNET PROTOCOL (IP) NETWORKS TO TRANSPORT MULTI-RATE SERIAL DATA STREAMS

      Heath, Doug; Polluconi, Marty; Samad, Flora; RT Logic Incorporated (International Foundation for Telemetering, 2006-10)
      As the rates and numbers of serial telemetry data streams increase, the cost of timely, efficient and robust distribution of those streams increases faster. Without alternatives to traditional pointto- point serial distribution, the complexity of the infrastructure will soon overwhelm potential benefits of the increased stream counts and rates. Utilization of multiplexing algorithms in Field- Programmable Gate Arrays (FPGA), coupled with universally available Internet Protocol (IP) switching technology, provides a low-latency, time-data correlated multi-stream distribution solution. This implementation has yielded zero error IP transport and regeneration of multiple serial streams, maintaining stream to stream skew of less than 10 nsec, with end-to-end latency contribution of less than 15 msec. Adoption of this technique as a drop-in solution can greatly reduce the costs and complexities of maintaining pace with the changing serial telemetry community.
    • 1588-ENHANCED VEHICLE NETWORK CONCEPT DEMONSTRATION

      Grace, Thomas; Roach, John; Naval Air Systems Command; Teletronics Technology Corporation (International Foundation for Telemetering, 2006-10)
      CTEIP has launched the integrated Network Enhanced Telemetry (iNET) project to foster advances in networking and telemetry technology to meet emerging needs of major test programs as well as within the Major Range and Test Facility Base’s. This paper describes one objective of the vNET concept demonstration to provide a test vehicle instrumentation network architecture that can support additional capabilities for data access to the test vehicle. Specifically, this paper addresses the expansion of the current concept demonstration with the incorporation of the IEEE- 1588 standard as the basis for a network time distribution mechanism. Near-term network-based data acquisition systems will likely consist of a mix of standard IRIG 106 timekeeping and IEEE- 1588 timekeeping; in this paper we will examine the ramifications of using the two approaches with the same test vehicle instrumentation system.
    • A DESIGN OF A DIGITALLY CONTROLLABLE WIDEBAND MICROWAVE RECEIVER

      Huang, Heng; Legarsky, Justin; Lei, Qiang; University of Missouri-Columbia; Brigham Young University (International Foundation for Telemetering, 2006-10)
      Radar echo sounders provide a safe, inexpensive and effective means of obtaining ice sheet thickness. As the roughness of ice surface/subsurface depends on the radio wavelength, wideband radar sensors can provide flexibility for ice thickness measurement under areas with various surface conditions. This paper presents the design of a digitally controllable wideband microwave receiver for a potential radar sounding system. Its radio frequency (RF) frequency ranges from 50 to 500 MHz, while the intermediate frequency (IF) bandwidth is 20 MHz. The receiver provides eight channels for different RF band choices, as well as a number of convenient gain settings. Testing measurements have also been conducted to verify the design requirements.
    • AUTOMATION SYSTEM FOR THE FLIGHT TEST LABORATORY (SALEV)

      Sousa, Lucas Benedito dos Reis; Leite, Nelson Paiva Oliveira; Walter, Fernando; Cunha, Wagner Chiepa; CTA - Grupo Especial de Ensaios em Vôo; ITA - Divisão de Eletrônica (International Foundation for Telemetering, 2006-10)
      A novel Automation System for the Flight Test Laboratory (SALEV) is developed in full compliance with EA-4/02 Standard (i.e. Expression of the Uncertainty of Measurement in Calibration) to compute the uncertainty of the measurement at the calibration laboratory of the Flight Tests Group (GEEV). The GEEV performs flight test campaigns to certificate and/or develop aircrafts and its systems. Then, flight tests instrumentation (FTI) systems are developed and installed in the test bed. The FTI data acquisition complies with IRIG Standard. The FTI is composed by a data acquisition system, which performs signal conditioning, sampling and quantization of all measurements provided by a set of transducers. All parameters are coded in a PCM format and represented in a non-dimensional numerical form (i.e. counts).To allow the establishment of a relation between the non-dimensional form and the physical quantity, a calibration process is carried out to provide the coefficients of a calibration curve. This process is also used to determine the systematic and random errors (i.e. the uncertainty). The accuracy and reliability of calibration process should comply with the requirements, which are customized for each flight test campaign. The satisfactory performance of the SALEV calibration process is achieved by automation in all steps. The SALEV development is presented, which includes the following steps: · Database definition; · Study of all steps and parts that forms the calibration process (i.e. from transducer to final uncertainty determination) to determine its associated uncertainties; · Automation of the entire calibration process (including the process itself up to the effective control of standard and instruments); · Development of algorithms to compute the uncertainty compliant with EA 4/02; and · System validation in compliance with ISO/IEC 17025. As result of the SALEV operation, it could be verified that measurement quality was improved, and the required time for calibration was substantially reduced. Also the standardization of this process allows failures forecast due to aging of systems parameters (i.e. bias).
    • Translation of L and S Band Tracking Assets to X Band High Dynamic Testing

      Winstead, Michael (International Foundation for Telemetering, 2006-10)
      Recent Constraints on the use of L and S band spectrum led to the search for additional Frequency Domain Bandwidth augmentation for test range telemetry needs. The ITU (International Telecommunications Union) approved X band region is listed as 7000 MHz to 8500 MHz for telemetry space applications. Bandwidth is available within this domain subject to the WARC (World Administrative Radio Consortium) approvals. This paper describes tests and presents results illustrating methodology that is available, and which can be used for conversion of S-band assets to the X band spectral region.
    • DUAL-BAND SWITCHED BEAM SYSTEM WITH HIGH FREQUENCY RATIO (1:1.8) FOR TELEMETRY APPLICATIONS

      Lee, Jung Kyu; De Flaviis, Franco; University of California, Irvine (International Foundation for Telemetering, 2006-10)
      In this paper, we propose a dual-band switched beam system operating at 4.05 and 7.4 GHz. This system comprise of a dual frequency Butler matrix feeding a microstrip antenna array. Very good agreement is shown between measured and simulated data. The system can provide a tilted beam of ±13° and ±48° at the lowest frequency band and ±9° and ±27° at the higher frequency band.
    • AN AFFORDABLE ARCHITECTURE FOR SATELLITE COMMUNICATIONS ON-THE-MOVE (COTM) ANETENNA SYSTEMS

      Gargasz, John; DRS CODEM SYSTEMS, INC. (International Foundation for Telemetering, 2006-10)
      There is a growing demand for an affordable Satellite Communications On-The-Move (COTM) Antenna system to serve Military and high commercial requirements. Current COTM architectures do not meet the Government’s price point objectives and thus are not effective production solutions. DRS Codem Systems has developed an affordable COTM the move antenna system architecture that meets the market price point while maintaining superior technical performance. The core elements of the architecture include: low-cost antenna reflector technology, integrated navigation sensors, integrated antenna control electronics with intelligent sensor fusion, maximum use of COTS components and an overall design intended to meet MILSpec environments. We have also selected X-band as the initial band for operation enabling a low-cost design and reliable network performance.