• In-Bore Acceleration Measurements of an Electromagnetic Gun Launcher

      Bukowski, Edward F.; Brown, T. Gordon; Brosseau, Tim; Brandon, Fred J.; Aberdeen Proving Ground; Dynamic Science Inc. (International Foundation for Telemetering, 2008-10)
      The US Army Research Laboratory has been involved in the design and implementation of electromagnetic gun technology for the past several years. One of the primary factors of this research is an accurate assessment of in-bore structural loads on the launch projectiles. This assessment is essential for the design of mass-efficient launch packages for electromagnetic guns. If not properly accounted for, projectile failure can result. In order to better understand the magnitude of the in-bore loads, a data-recorder was integrated with an armature and on-board payload that included tri-directional accelerometers and magnetic field sensors. Several packages were launched from an electromagnetic railgun located at Aberdeen Proving Ground, MD. Substantial effort was placed on soft-catching the rounds in order to facilitate data recovery. Analysis of the recovered data provided acceleration and magnetic field data acquired during the launch event.
    • Using the GNU Radio Platform to Implement a Telemetry Receiver

      Newcomb, Gregory; Punnoose, Ratish J.; Sandia National Laboratories (International Foundation for Telemetering, 2008-10)
      GNU Radio is a flexible software radio platform that enables custom radio development. It consists of open-source signal processing blocks that can be integrated into custom applications. The Universal Software Radio Peripheral (USRP) is a hardware board that works well with the GNU Radio suite. The schematics and firmware on this board are also open-source. As such, this GNU Radio and the USRP hardware form a rapid prototype platform for software radio based telemetry receivers.
    • Wireless Sensor System for Airborne Applications

      Pellarin, Steve; Grossman, Hy; Musteric, Steven; Teletronics Technology Corporation; Eglin Air Force Base (International Foundation for Telemetering, 2008-10)
      Adding an instrumentation / telemetry system to a test article has historically required an intrusive installation. Power, wiring, and available space typically present significant challenges. There has been a long-standing need in the test and training community for a non-intrusive, flexible and modular instrumentation and telemetry system that can be installed on an aircraft or other test article without the need for permanent modifications. In addition, as available space in aircraft weapon bays, small weapons, and unmanned vehicles becomes a premium, the miniaturization of remote sensors and telemetry units becomes critical. This paper describes the current status of the Advanced Subminiature Telemetry System (ASMT) Initial Test Capability Project. It discusses the progress to date in fielding an operational, wireless sensor system that may be installed on the aircraft skin using an Electro-Cleavable adhesive as an alternative to conventional mounting methods. The wireless sensor utilizes the Wireless Communications Standard for Wireless Personal Area Network™ (WPAN™) IEEE 802.15 Working Group standard (commonly referred to as Bluetooth) to establish communication between the sensor and controller modules. Results of aircraft ground testing for EMI compatibility with aircraft systems will be presented. It is also expected that actual flight test results will be available by the time the paper goes to publication.
    • Managing Instrumentation Networks

      Pesciotta, Eric; Teletronics Technology Corporation (International Foundation for Telemetering, 2008-10)
      As traditional data acquisition systems give way to network-based data acquisition systems a new approach to instrumentation configuration, management and analysis is required. Today, most flight test programs are supported by traditional instrumentation systems and software. Pockets of network-based systems exist but are typically entirely new, closed systems. Relatively soon, test articles will emerge with a mixture of equipment. The merger of traditional and networked instrumentation is inevitable. Bridging the gap in software tools is a non-trivial task. Network-based data acquisition systems provide expanded flexibility and capabilities well beyond traditional systems. Yet pre-existing equipment requires traditional configuration and analysis tools. Traditional flight test software alone cannot fully exploit the added benefits gained from such mergers. The need exists for a new type of flight test software that handles existing instrumentation while also providing additional features to manage a network of devices. Network management is new to flight test software but a thoughtful implementation can facilitate easy transition to these modern systems. This paper explores the technologies required to satisfy traditional system configuration as well as the less understood aspects of network management and analysis. Examples of software that meet or exceed these requirements are provided.
    • The Development of a Flight Test Real Time GPS Navigation Tool (GNAV)

      Leite, Nelson Paiva Oliveira; Rocha, Israel Cordeiro; Walter, Fernando; Hemerly, Elder Moreira; Grupo Especial de Ensaios em Vôo; Centro de Computação da Aeronáutica de Brasília; Instituto Tecnológico de Aeronáutica (International Foundation for Telemetering, 2008-10)
      The real time acquisition and monitoring of the aircraft trajectory parameters is essential for the safety of the flight tests campaigns held by most of the tests centers. Nowadays the us age of an airborne GPS receiver as the main sensor for these parameters has become the preferred solution for the Flight Tests Instrumentation (FTI) systems. The main problem arises when it is required a high accuracy for these measurements (e.g. air data calibration) where the solution is achieved through differential GPS techniques. The integration of this solution requires the acquisition and the correlation of the pseudorange and phase measurements for all GPS satellites in view observed by both base and rover GPS receivers. To avoid the usage of an additional uplink for the GPS differential corrections (i.e. from the base receiver to the rover), it was developed a novel solution where the GPS observables acquired by the rover receiver are merged into the FTI PCM data stream and processed in the Telemetry ground station by a Real Time GPS Navigation (GNAV) tool together with the GPS observables acquired by the base receiver. The GNAV development is divided into several phases where the accuracy for the trajectory parameters and the complexity of the solution increases. The prototype system was built and evaluated against the post-mission Ashtech PNAV® tool and the initial tests results show a satisfactory performance for the GNAV. The tests profiles are fully compliant with the Federal Aviation Administration (FAA) Advisory Circular (AC) 25-7A.
    • An Airborne Network Telemetry Link for the iNET Technical Demonstration System

      Temple, Kip; Laird, Daniel; Edwards Air Force Base (International Foundation for Telemetering, 2008-10)
      A previous paper was presented detailing the design and testing of the first networked demonstration system (ITC 2006) for iNET. This paper extends that work by testing a commercial off the shelf (COTS) solution for the wireless network connection of the Telemetry Network System (TmNS). This paper will briefly discuss specific pieces of the airborne and ground station system but will concentrate on the new wireless network link, how it was tested, and how well it performed. Flight testing results will be presented accessing the performance of the wireless network link.
    • PAM-Based Timing Synchronization for ARTM Modulations

      Perrins, Erik; Bose, Sayak; Wylie-Green, Marilynn P.; University of Kansas; Nokie Siemens Networks (International Foundation for Telemetering, 2008-10)
      A reduced-complexity decision-directed timing recovery method for continuous phase modulation (CPM) is presented. The timing recovery method is based on the pulse amplitude modulation (PAM) representation - or Laurent representation - of CPM, and is applied to the family of three telemetry modulations: PCM/FM, SOQPSKTG, and ARTM CPM. This work is the next step in an ongoing effort to develop reduced-complexity PAM-based receiver methods for aeronautical telemetry. We quantify the steady-state tracking accuracy of the proposed timing recovery method and show that it performs very close to the theoretical limit given by the modified Cramer-Rao bound (MCRB).We also demonstrate that the proposed method is free of false-lock points for all three modulations.
    • Technology Trades in IP-Based Telemetry Networks

      Kenney, Joshua D.; Moodie, Myron L.; Ragsdale, Gary L.; Grace, Thomas B.; Southwest Research Institute; Naval Air Systems Command (NAVAIR) (International Foundation for Telemetering, 2008-10)
      The integrated Network Enhanced Telemetry (iNET) project established a test article standards working group to define open standards for network components and interfaces for test articles in the aeronautical test environment. Its aim is to utilize the growth of Internet technologies for telemetry networks and ensure interoperability among network devices. This paper describes the technology background and the current technology trades of an IP-based network paradigm used in producing standards for test article networks. Specifically, the paper will include descriptions of selected network technologies as applied to test data and time distribution within test articles.
    • Considerations for Deploying IEEE 1588 V2 in Network-Centric Data Acquisition and Telemetry Systems

      Newton, Todd; Grim, Evan; Moodie, Myron; Southwest Research Institute (International Foundation for Telemetering, 2008-10)
      Network-centric architectures continue to gain acceptance in data acquisition and telemetry systems. Though networks by nature impose non-deterministic transit time of data through a given link, the IEEE 1588 standard provides a means to remove this jitter by distributing time messages to the data acquisition units themselves. But like all standards, they evolve over time. The same is true with IEEE 1588, which is releasing its second version later this year. This paper discusses the challenges of the first version of the IEEE 1588 standard that Version 2 set out to address, potential challenges with Version 2, and interoperability issues that may arise when incorporating a mixture of Version 1 and Version 2 devices.
    • Application of a High Data Rate Modem (HDRM)

      Orndorff, Tim; Puri, Amit; Smiley, Mike; Connell, John; CVG/Avtec Systems, Inc. (International Foundation for Telemetering, 2008-10)
      A traditional Receiver, Modulator, Bit Synchronizer, Frame Synchronizer and Front-End Processor (FEP) with local RAID storage from numerous satellite ground station equipment providers is typically used to satisfy current needs in mission ground stations. The development of Software Defined Radios (SDRs) with reprogrammable personalities has led to the consolidation of these processing elements, and will become the standard for years to follow. CVG-Avtec Systems, Inc. has been a pioneer in the SDR industry, integrating several ground station functions into a one system solution. Its High Data Rate Modem (HDRM) architecture replaces racks of previous generation equipment, providing greater functionality in a smaller footprint. The Field Programmable Gate Array (FPGA) based HDRM is a one system solution that inputs Intermediate Frequency (IF) data and outputs packetized data over IP for data distribution. These new architectures are capitalizing on the revolution in electronics and networking technologies. This paper will discuss the architecture of the HDRM and how it optimizes ground station data processing in a high-rate environment.
    • New Results in Unitary Space-Time Code Construction and Comparison to Upper Bounds

      Panagos, Adam; Potter, Chris; Kosbar, Kurt; Dynetics, Inc.; Missouri University of Science and Technology (International Foundation for Telemetering, 2008-10)
      Unitary space-time codes are a coding technique for unknown (i.e. non-coherent) multiple-input multiple-output (MIMO) channels. The unitary constellation symbol-error rate performance is determined by the diversity product and diversity sum metrics of the constellation. Numerous techniques have been presented over the last few years for constructing unitary space-time codes with continually improving diversity products and sums. Other work has focused on determining bounds on the optimal diversity product and sum for a given number of transmit antennas and constellation size. This paper presents a comprehensive survey of known construction techniques and bounds for unitary space-time codes, and also reports a variety of new constellations that have been constructed with improved diversity product or sum. These new constellations are documented along with a list of the currently best known codes and bounds. In many cases, a large gap between the bound and best known constellation exist. This result suggests areas of focus for improved constructions or tighter bounds.
    • An Analysis on the Coverage Distance of LDPC-Coded Free-Space Optical Links

      Borah, Deva K.; Luna, Ricardo; Tapse, Hrishikesh; New Mexico State University (International Foundation for Telemetering, 2008-10)
      We design irregular Low-Density Parity-Check (LDPC) codes for free-space optical (FSO) channels for different transmitter-receiver link distances and analyze the error performance for different atmospheric conditions. The design considers atmospheric absorption, laser beam divergence, and random intensity fluctuations due to atmospheric turbulence. It is found that, for the same transmit power, a system using the designed codes works over much longer link distances than a system that employs regular LDPC codes. Our analysis is particularly useful for portable optical transceivers and mobile links.
    • Analysis and Application Scenarios for Telemetry Data Transmission and Synchronisation over Wireless LAN

      Cranley, Nikki; Corry, Diarmuid; ACRA Control Inc. (International Foundation for Telemetering, 2008-10)
      The use of IEEE 802.11 Wireless LAN (WLAN) technology offers numerous advantages over wired Ethernet including high bandwidth, device mobility, and the elimination of network wiring within the aircraft. With such benefits, there are certain caveats associated with the ability and performance of WLAN technology to carry time-sensitive and critical telemetry data using current IEEE 802.11 WLAN standards. In this paper, the limitations of WLAN for real-time data transmission are experimentally investigated. In particular, it will be shown how the fundamental wireless access mechanism and contention impact on the WLANs ability to carry real-time data. Although telemetry data is constant, the wireless access mechanism causes the WLAN throughput and per-packet delays to vary over time. Moreover, with the increased popularity of the IEEE 1588 Precision Time Protocol (PTP), the ability of the WLAN to provide time synchronisation is investigated. It is shown that asymmetric data loads on the uplink and downlink introduce synchronization errors. To mitigate some of these issues, this paper will discuss how the Quality of Service (QoS) Enabling WLAN standard, IEEE 802.11e, can be used to provide differentiated services and prioritised transmission for critical data.
    • WSMR Telemetry Capabilities: Today's Technology in Telemetry

      Aguirre, Zoe; Beltran, Gabe; White Sands Missile Range (International Foundation for Telemetering, 2008-10)
      White Sands Missile Range is the largest overland test range in North America occupying over 3,200 square miles in Southern New Mexico and nearby territory. One of the most critical test elements at White Sand Missile Range is it's capabilities in the telemetry field. Much significant advancement in technology has given WSMR and the entire electronics world the ability to achieve new levels of data acquisition that were not achievable a decade ago. And as attention to our nation's defense is of high priority, White Sands Missile Range provides to highest levels of telemetry competence in the Western Hemisphere.
    • Dual Antenna Use on a GPS Receiver

      Altan, Han; Honeywell International (International Foundation for Telemetering, 2008-10)
      Due to vehicle dynamics in mobile systems, GPS signal reception may be blocked by the body of the vehicle. This paper discusses various studies made on some vehicles such as the Space Shuttle, various aircraft, and analyzes the implementation of dual GPS antenna systems. Constructive and destructive interference characteristics of signal combining are considered. The author suggests an approach which uses a delay line on one of the antennas while analyzing the front end C/N0 needed for L1 GPS reception. An embedded Excel spreadsheet provides a front-end Noise Figure (NF) calculation tool based on user selected parameters.
    • Hardware Discussion of a MIMO Wireless Communication System Using Orthogonal Space Time Block Codes

      Potter, Chris; Kosbar, Kurt; Panagos, Adam; Missouri University of Science and Technology; Dynetics, Inc. (International Foundation for Telemetering, 2008-10)
      Although multiple-input multiple-output (MIMO) systems have become increasingly popular, the existence of real time results to compare with those predicted by theory is still surprisingly limited. In this work the hardware description of a MIMO wireless communication system using orthogonal space time block codes (OSTBC) is discussed for two antennas at both the transmitter and receiver. A numerical example for a frequency flat time correlated channel is given to show the impact of channel estimation.
    • Quantifying Coding Gain from Telemetry Data Combining

      Forman, Michael A.; Condreva, Ken; Kirchner, Gary; Lam, Kevin; Sandia National Laboratories (International Foundation for Telemetering, 2008-10)
      A method for combining telemetry data and quantifying the resulting coding gain for a ballistic missile test flight is presented. Data received from five ground stations in 54 data files with 18 million intermittent frames is combined, to create a single file with 1.5 million continuous frames. Coding gain provided by data combining is as high as 30 dB, with a useful improvement of 5 dB at boost and terminal stages. With frame reconstruction techniques, erroneous words in a frame are reduced from 2.1% to 0.12 %.
    • Spectral Analysis for Spacecraft Analog Telemetry Behavior

      Losik, Len; Failure Analysis (International Foundation for Telemetering, 2008-10)
      Spectral analysis decomposes a signal into its frequency components. Engineers can use spectral analysis to decompose Satellite and spacecraft telemetry behavior from space to provide a new tool to advance space vehicle reliability. The same tools used by RF and digital signal design engineers for identify signal integrity offers new understanding for telemetry behavior from space. Analysis illustrates the harmonic properties of telemetry behavior as a function of time, amplitude, frequency and phase. Expanding spectral analysis to satellites and spacecraft illustrates their fundamental harmonic properties. This information can be used to improve vehicle reliability and define vehicle and ground station telemetry system design performance parameters and reduce risk of catastrophic satellite and spacecraft failure.
    • Adjacent Channel Interference for Turbo-Coded APSK

      Rice, Michael; Shaw, Christopher; Brigham Young University (International Foundation for Telemetering, 2008-10)
      A study of the effects of interference caused by adjacent channels on the performance of turbo-coded 16- and 32-APSK. Included in our discussion is the spectral regrowth in the nonlinear power amplifier when driven by a non-constant envelope modulation. Ultimately, we present a set of channel spacing guidelines when using turbo-coded APSK for aeronautical telemetry.
    • An Economic Method to Increase Equipment Rack Shielding

      Ridgeway, Robert; Newton, Henry; Digi International Inc.; National Radio Astronomy Observatory (International Foundation for Telemetering, 2008-10)
      The ALMA Project is developing a 66 antenna radio astronomy array on a 5000 meter mountain in Chile. Radio astronomy depends on a radio frequency quiet area. The remote mountain top is ideal for such a radio astronomy array. However, RFI from equipment inside one type of antenna had a path loss of 13 dB to its feed area, when measured at 100 GHz. Carbon filled foam is being used to enhance shielding to reduce the negative effect of local radio frequency interference (RFI). This foam has been measured and verified to be effective from 1 to 100 GHz.