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.
    • Best Source Selection on Encrypted Data

      Guadiana, Juan M.; White Sands Missile Range (International Foundation for Telemetering, 2006-10)
      The size of the range at White Sands means multiple acquisition sites are needed to properly cover a typical vehicle trajectory. As vehicle complexity increase, the need for robust acquisition grows. Multiple acquisition sites are needed to provide as complete coverage as practical. Space Diversity combining would provide a single composite source for all the displays and recording, but this is not practical due to the large distances between acquisition sites. Instead a composite is made from the various sites by correlation on non-encrypted (or decrypted) data. The previous best source selector, a frame synch histogrammer, could produce encrypted and decrypted composites. Some of our customers have missed the encrypted composites, hence the subject is revisited to encourage development. This paper reviews post decryption correlation and then focuses on correlating on encrypted data. The encryption serves to eliminate the ambiguities that are inherent in decrypted (nonencrypted) signals. So, it may be possible to accomplish this with a small correlator. The expected performance would be similar to that of correlated composites on decrypted or unencrypted data. The typical configuration would be considerably smaller as well since only two decrypters would be needed. One decrypter alone would be insufficient and could not resolve the case where only one site has data and the remaining sites have noise. When there is no correlation the correct site cannot be resolved. Testing these compositing methods is also discussed, as a good test method also provides insight on how the compositor should work.

      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).

      Tsai, Chiou-Wei; Cagley, Richard E.; Iltis, Ronald A.; University of California; Toyon Research Corporation (International Foundation for Telemetering, 2006-10)
      Spatial multiplexing (SM) systems have received significant attention because the architecture offers high spectral efficiency. However, relatively little research exists on optimization of SM systems in the presence of jamming. In a spatially uncoded SM system, such as V-BLAST, the channel state information is assumed to be unavailable a priori at both transmitter and receiver. Here, Kalman filtering is used to estimate the Rayleigh fading channel at the receiver. The spatial correlation of the jammer plus noise is also estimated, and spatial whitening to reject the jammers is employed in both the Kalman channel estimator and detector. To avoid the exponential complexity of maximum-likelihood (ML) detection, the QRD-M algorithm is employed. In contrast to sphere decoding, QRD-M has fixed decoding complexity of order O(M), and is thus attractive for hardware implementation. The performance of the joint Kalman filter channel estimator, spatial whitener and QRD-M detector is verfied by simulations.
    • The SoftDecom Engine

      Benitez, Jesus; Guadiana, Juan; Torres, Miguel; Creel, Larry; White Sands Missile Range (International Foundation for Telemetering, 2006-10)
      The software decommutator was recently fielded at White Sands to address the requirements of a new missile test program. This software decommutator is rewritten as a simple C program Function or Class with a simple interface. The function and an Interface Control Definition (ICD) comprise the SoftDecom Engine (SDE). This paper addresses how an SDE can deliver Enterprise Wide Portability, not only that of the SDE, but more importantly a test program!s Verification & Validation (V&V). The crux of the portability issue is reduced to defining the interface of the SDE. In the simplest manifestation only two interfaces are needed and one is a given. The input structure is defined by the telemeter minor frame with time appended if desired. The output structure is no more than an array containing the parameters required. The ICD could be generalized into a standard for most applications, but that isn!t necessary, as the structures are simple, hence easy to adapt to anyway. This new paradigm!s importance will flourish on industries irreversible migration to faster and more complex telemeters. The paper reviews the relative ease that software exhibits when addressing very complex telemeters. With confidence it may be said “ if the telemeter format can be described in writing, it can be processed real time”. Also discussed are tasks that normally require specialized or customized and expensive equipment for example, merged streams, complex simulations and recording and reproducing PCM (sans recorder). Hopefully, your creativity will be engaged as ours has been.
    • Current Status of Integrating GPS and Flight Termination Capabilities into a Missile Telemetry Section

      Kujiraoka, Scott R.; Fielder, Russell G.; NAVAIR (International Foundation for Telemetering, 2006-10)
      Last year (2005), a paper discussed the efforts of integrating Joint Advanced Missile Instrumentation (JAMI) Program components (JAMI TSPI Unit - JTU, and the Flight Termination Safe & Arm device - FTS&A), commercial off the shelf parts (Flight Termination Receivers, Telemetry Transmitter, Encryptor and Thermal Batteries) and in-house developed devices (PCM Encoder and Tri-band Antenna with integrated Limiter, Filter, & Amplifier) into a five-inch diameter Missile Telemetry (TM) Section. This retrofitted missile would be captive-carried on a F/A-18 jet. This paper is a continuation of that one presented at the 2005 International Telemetry Conference (ITC) Symposium. It annotates the latest status of the JAMI Effort, as well as the Follow-On Effort to qualify the Missile TM Section for an actual missile firing. This would include the developmental and flight qualification efforts for the Explosive Train (Detonation Cord-to-Cutter Ring Assembly) and Thermal Batteries.

      Kelkar, Anand; Lamarra, Norm; Gonzalez, Daniel; Creative Digital Systems; Malibu Research Associates (International Foundation for Telemetering, 2006-10)
      A Synthetic Beamforming antenna was built for Airborne Telemetry. Low-Noise Block-converters translated RF to IF suitable for direct analog-to-digital conversion. Then all telemetry functions were performed digitally via parallel FPGAs for 10 independent sources. Monopulse tracking and optimal diversity combination was performed using 4 antenna quadrants at two orthogonal polarizations. Novel estimation approaches drove digital demodulation, symbol- and bit- synchronization. Final telemetry outputs include: digital, analog (video), and analog IF (e.g., for downlink relay). This program has incubated several concepts that we believe have the combined potential to significantly improve the future of telemetry.

      Rice, Michael; Nelson, Tom; Brigham Young University (International Foundation for Telemetering, 2006-10)
      Motivated by the success of the ARTM Tier-1 modulation known as Shaped Offset QPSK, this paper examines whether improved spectral efficiency can be achieved using an a Shaped Offset 8PSK. Three possible interpretations of this question are examined and it is shown that there does not appear to be a shaped offset 8-PSK in the context of aeronautical telemetry.

      Wolf, Glen; Ortigoza, Saul; Streich, Ronald G.; Edwards Air Force Base (International Foundation for Telemetering, 2006-10)
      A rocket launch, as high dynamics target, was used to demonstrate X-band tracking and also to verify high bit rate frequency planning while demonstrating significant bandwidth reduction with IRIG standard advanced modulation methods. X-band tracking by a modified 8-foot mobile telemetry antenna was excellent. Three separate S-band transmitters with three separate wraparound antennas were launched as a piggyback payload on an Enhanced Orion sounding rocket at White Sands Missile Range (WSMR) to compare the performance of 10 Mbs and 20 Mbs bit error rate (BER) pattern data transmission from CPFSK, FQPSK-JR and ARTM CPM modulation formats under high dynamic conditions. The test is more remarkable in that another S-band wideband spread spectrum signal was also transmitted with good success. These results show that all three modulation methods performed well during ignition and liftoff, low aspect angle (receiving through the rocket motor plume during ascent from a tracker near the launch pad), spin stabilization antenna lobe fades and payload tumbling. Spectrum pictures are provided to show the dramatic reduction in transmission bandwidth from CPFSK to FQPSK-JR to ARTM CPM. Confirmation of the preflight RF adjacent channel interference planning procedures from IRIG 106-05 is described by spectrum pictures and data quality measurements.
    • Single Bounce Air to Ground Communication Channel Capacity for MIMO Applications

      Kosbar, Kurt; Potter, Chris; University of Missouri (International Foundation for Telemetering, 2006-10)
      This paper addresses the air-to-ground communication problem, where multiple transmit antennas are used on the aircraft to combat multi-path interference. The channel is assumed to have a line-of-sight component and a single ground reflection. Multiple input multiple output (MIMO) techniques can be used in this situation, to increase the reliability and data rate. In this paper we discuss how the MIMO channel capacity changes, with the aircraft antenna configuration, altitude, velocity, range, and a number of other parameters. For comparison, the MIMO results are compared to systems which have single antennas at the transmitter, at the receiver, or at both ends.

      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.
    • IEEE1588 – A solution for synchronization of networked data acquisition systems?

      Corry, Diarmuid; ACRA CONTROL INC (International Foundation for Telemetering, 2006-10)
      One of the problems for manufacturers and users of flight test data acquisition equipment, is to guarantee synchronization between multiple units acquiring data on the vehicle. Past solutions have involved proprietary interconnects and multiple wire installations increasing weight and complexity and reducing inter-operation of units. This problem has become particularly important given the trend towards commercial busses, especially Ethernet, as a system interconnect. The IEEE1588 standard offers a way to transmitting time accurately over Ethernet. This paper discusses the standard, how it might be implemented, and examines the issues involved in adopting this standard for flight test data acquisition. A particular implementation that results in a synchronized four-wire Ethernet based distributed data acquisition system is discussed in section 3.
    • An Overview Of An Instrumentation Hardware Abstraction Language

      Hamilton, John; Fernandes, Ronald; Koola, Paul; Jones, Charles H.; Knowledge Based Systems, Inc; Edwards Air Force Base (International Foundation for Telemetering, 2006-10)
      In this paper we provide the motivation for a neutral instrumentation hardware abstraction language that is focused on the description and control of instrumentation systems and networks. We also describe the design approach and structure of such a language that meets the needs. The language design is described according to the three roles it must serve: (1) as a descriptive language for specifying and describing the components and configuration of an instrumentation system, (2) as a command language for issuing configuration and data commands to instrumentation hardware and (3) as a query language for requesting the current state of instrumentation hardware.
    • 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.

      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.

      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.

      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.

      Xiangwu, Gao; Juan, Lin; Zhengguang, He; Beijing Institute of Astronautical Systems Engineering; China Academy of Launch Vehicle Technology (International Foundation for Telemetering, 2006-10)
      XX launch vehicle has been flying onboard video system which includes video cameras, data compression devices and channel switch device for the second Chinese spaceflight. The camera is a PAL analog camera that been sampled and compressed by compression device. The compressed digital video data is combined with telemetry data into the telemetry radio channel. Lighting is provided by sunlight, or a light has been equipped when sunlight is unavailable. IRIG-B timing is used to correlate the video with other vehicle telemetry. The video system’s influences to the vehicle flight have been decreased to minimum.

      May, Linda R.; Honeywell Technology Solutions, Inc.; NASA Goddard Space Flight Center (International Foundation for Telemetering, 2006-10)
      “Wind Weighting” is the process of assessing the effect of wind on a launch vehicle and determining launcher settings which would counteract that effect. This paper discusses the advantages of using GPS radiosondes to determine wind profiles over the historical method of tracking balloon positions with radar for the purposes of Wind Weighting. The primary advantages are lower costs and greater portability. Also presented is evidence of improved accuracy and reliability. Engineering testing is described and test results are reported.

      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.