• NETWORK-BASED DISTRIBUTED DATA ACQUISITION AND RECORDING FOR SMALL SYSTEMS

      Hildin, John; Teletronics Technology Corporation (International Foundation for Telemetering, 2007-10)
      Some of the first applications of network-based data acquisition systems have been for large aircraft. These systems contained numerous network nodes including data acquisition units, switches, recorders, network management units, and others. One of the desirable aspects of a networked-based system is the ability to scale such a system to meet increasing test requirements. Similarly, these systems lend themselves to scaling down, as well, to meet the testing needs of smaller test articles. These needs may include fewer nodes and/or physically smaller components. The testing of smaller vehicles places slightly different requirements on the testing process. In general, there is a greater need for real-time analysis, flexibility and ad-hoc testing. This paper will attempt to show how a small to medium sized test article can benefit from the same powerful, feature-rich network-based data acquisition and recording system as used on larger programs. The paper will also show how a smaller system can deliver on this promise without sacrificing performance and functionality.
    • A NEXT GENERATION AIRCRAFT POWER MONITORING SYSTEM

      Grossman, Hy; Teletronics Technology Corporation (International Foundation for Telemetering, 2007-10)
      Historically, aircraft power monitoring has required the use of multiple signal conditioning functions to measure various parameters including voltage, current, frequency and phase. This information was then post processed to determine the characteristics of the 3-phase power quality on the aircraft. Recent developments in embedded DSP processors within signalconditioning systems provide the instrumentation engineer with expanded capabilities for realtime on-board power quality monitoring. Advantages include reduced space and bandwidth requirements and minimal wiring intrusion. For each phase, output data may include peak positive and negative voltages and currents, peak-to-peak, average and RMS voltages and currents, phase power (real and apparent), phase power factor, phase period (frequency), phase shift measurement from phase 1 (the reference phase) to phase 2, and from phase 1 to phase 3. In addition, a Fast Fourier Transform (FFT) is performed on each phase voltage to provide Total Harmonic Distortion measurements. This paper describes the methods employed in the implementation of these functions on a single signal-conditioning card in order to provide detailed information about the power quality of a three-phase aircraft power source.
    • ON REDUCED COMPLEXITY TECHNIQUES FOR BANDWIDTH EFFICIENT CONTINUOUS PHASE MODULATIONS IN SERIALLY CONCATENATED CODED SYSTEMS

      Perrins, Erik; Kumaraswamy, Dileep; University of Kansas (International Foundation for Telemetering, 2007-10)
      Serially concatenated coded (SCC) systems with continuous phase modulations (CPMs) as recursive inner codes have been known to give very high coding gains at low operative signal to noise ratios (SNRs). Moreover, concatenated coded systems with iterative decoding approach the bit error rate (BER) bounds given by the maximum likelihood (ML) criterion. Although SCC systems by themselves are reduced complexity systems when compared to the ML decoding, when very highly bandwidth efficient CPMs such as pulse code modulation /frequency modulation (PCM/FM) is used [1], they present a problem of extremely high decoding complexity at the receiver. The complexity of a CPM is described by the size of its trellis which is a function of the modulation index, the cardinality of the source alphabet and the length of the frequency pulse used. The surveyed complexity reduction techniques adopt approximations which will reduce the size of the trellis with minimal expense of power. In this paper, we present reduced complexity approaches to sub-optimally decode SCC PCM/FM by mainly two approaches - 1) Frequency pulse truncation. 2) Decision feedback.
    • OPERATOR INTERFACES FOR CONTROLLING THE SERIAL STREAMING TELEMETRY CHANNEL VIA A COMMAND AND CONTROL LINK

      Laird, Daniel T.; Edwards Air Force Base (International Foundation for Telemetering, 2007-10)
      The Central Test and Evaluation Incentive Program, (CTEIP) is developing Integrated Network Enhanced Telemetry (iNET) to extend serial streaming telemetry (SST) with a command and control link. Command link interfaces link remote Advanced Range Telemetry (ARTM) transmitters (Tx) and receivers (Rx), developed under the ARTM CTEIP project, via graphical user interfaces (GUI). The communication channel links the iNET Tx on a vehicle network (vNET) and the iNET Rx on a ground station network (gNET) via a single GUI. The command link is an essential part of the pending iNET Technology Demonstration.
    • OPTIMAL CONFIGURATION FOR NODES IN MIXED CELLULAR AND MOBILE AD HOC NETWORK FOR INET

      Dean, Richard; Babalola, Olusola; Morgan State University (International Foundation for Telemetering, 2007-10)
      As part of Morgan’s iNET development, the Mixed Cellular and Mobile Ad hoc Network (MCMN) architecture has been 1proposed to provide coverage to over-the horizon test articles. Nodes in MCMN are assigned to one of three possible modes- Ad hoc, Cellular or Gateway. We present architecture for the proposed MCMN and some performance analysis to characterize the network. The problem of organizing nodes in this mixed network with optimal configuration is significant. This configuration gives nodes ability to know the best mode to operate and communicate with other nodes. Node organization is critical to the performance of the mixed network and to improve communication. The configuration of nodes required to optimally organize nodes in MCMN is demonstrated. The problem of evaluating configuration parameters for nodes in a mixed network is a nonlinear and complex one. This is due to the various components like the number of nodes, geographical location, signal strength, mobility, connectivity and others that are involved. Clustering techniques and algorithms have been used in literature to partition networks into clusters to support routing and network management. A clustering technique is employed to dynamically partition the aggregate network into Cluster Cells (CCs). A gateway node is selected for each CC which relays traffic from the cellular to the Ad hoc and vice versa. A trade-off analysis of the cellular boundary is presented using the maximum of the minimum data rate in the network. Numerical analysis and experiments are provided to show that the coverage can be extended to test articles in over-the-horizon region. It is also shown that, when the network is well organized, performance is improved.
    • An Optimum Detector for Space-Time Trellis Coded Differential MSK

      Rice, Michael; Dang, Xiaoyu; Brigham Young University (International Foundation for Telemetering, 2007-10)
      The accuracy of channel estimation plays a crucial role in the demodulation of data symbols sent across an unknown wireless medium. In this work a new analytical expression for the channel estimation error of a multiple input multiple output (MIMO) system is obtained when the wireless medium is continuously changing in the temporal domain. Numerical examples are provided to illustrate our findings. Space-time (ST) coding using Continuous Phase Modulation (CPM) has spectral advantages relative to linear modulations. In spite of the spectral benefits, Space-Time Trellis Codes (STTC) using the CPM implementation of Minimum Shift Keying (MSK) scheme has inherent inphase and quadrature interference, when the received complex baseband signal is the input into the matchfilter to remove the shaped sinusoid pulses. In this paper a novel optimum transmitting and detecting structure for STTC-MSK is proposed. Treating the Alamouti scheme as an outer code, each STTC MSK waveform frame is immediately followed by the orthogonal conjugate waveform frame at the transmit side. At the receiver first orthogonal wave forming is applied, then a new time-variant yet simple trellis structure of the STTC-MSK signals is developed. This STTC-MSK detector is absolutely guaranteed to be I/Q interference-free and still keeps a smaller computation load compared with STTC-QPSK. Simulations are made over quasi-static AWGN fading channel. It is shown that our detector for ST-MSK has solved the I/Q interference problem and has around 2.8 dB gain compared with the Alamouti Scheme and 3.8 dB gain for bit error rate at 5 X 10^(-3) in a 2 by 1 Multiple Input Single Output system.
    • OVERVIEW OF AN INTEGRATED INSTRUMENTATION DATA SYSTEM USED BY THE F-35 LIGHTNING II FLIGHT TEST PROGRAM

      Vu, Doug; Berdugo, Albert; Lockheed Martin Aeronautics Co.; Teletronics Technology Corporation (International Foundation for Telemetering, 2007-10)
      The Joint Strike Fighter program is the largest DOD contract ever awarded. There are three F-35 Lightning II variations, each intended to meet the specific needs of the Air Force, Navy, Marine Corps, and U.S. Allies. The Data System required for this flight test program challenged the conventional ways used in instrumenting test aircraft. Typical data systems available today don’t provide the level of hardware and software integration required for today’s complex applications. For example, cockpit control panels, recording systems, TM transmitters, data acquisition systems and avionic bus interface units are all independent systems. Additionally, avionic bus catalogs, ground-based systems, and flight setup software have historically been independent components. This paper will describe the hardware and software components used by the F-35 flight test program to provide an integrated system. A special emphasis will be given to the methods used to accommodate rapid changes to the IEEE-1394B avionic bus catalog including the acquisition of that data, and the use of an IRIG-106 Chapter 10 distributed multiplexer / recorder system, which is being used simultaneously as a data acquisition system.
    • OVERVIEW OF F-22 UPGRADED INSTRUMENTATION SYSTEM

      Natale, Louis; Berdugo, Albert; Lockheed Martin Aeronautics Co.; Teletronics Technology Corporation (International Foundation for Telemetering, 2007-10)
      The F-22 flight test program used a traditional distributed data acquisition system and a non IRIG-106 Chapter 10 recording system for its flight test program. In addition, it required a separate and very large Harris DAU system to monitor and record avionic data buses carrying secure data. Due to the size, cost, and the obsolescence of the Harris DAU system and components, Lockheed evaluated replacement systems. TTC proposed to develop F-22 specific Fiber Optic avionics bus monitors and an avionics PCM Data Selector / Encoder as part of its distributed IRIG-106 Chapter 10 Multiplexer / Recorder system to replace the Harris DAU. This replacement system challenges the traditional system approach used in many flight test programs. This paper describes the evolutionary process to design two independent distributed data acquisition and recording systems handling data with different classification levels. The data separation is maintained by way of system wiring, proper hardware that holds no residual data once power is removed, different transmission channels, hardware-based message blocking, and a separate IRIG-106 Chapter 10 multiplexing / recording system.
    • PERFORMANCE CHARACTERIZATION OF MULTI-BAND ANTENNAS FOR AERONAUTICAL TELEMETRY

      Temple, Kip; Jefferis, Robert; Selbrede, Robert; Edwards Air Force Base (International Foundation for Telemetering, 2007-10)
      This paper baselines the performance of common, single band telemetry blade antennas in two telemetry bands and compares that performance to two very differing multi-band antenna designs. A description of each antenna is presented followed by flight testing results and conclusions. Results are in the form of received signal strength versus geographic location, derived in-flight antenna patterns, link availability, and bit error analysis.
    • PERFORMANCE COMPARISON OF SOQPSK DETECTORS: COHERENT VS. NONCOHERENT

      Bruns, Tom; L-3 Communications Nova Engineering (International Foundation for Telemetering, 2007-10)
      Shaped Offset Quadrature Shift Keying (SOQPSK) is a spectrally efficient modulation that has been promoted in the airborne telemetry community as a more spectrally efficient alternative for legacy PCM/FM. First generation demodulators for SOQPSK use coherent detectors which achieve good bit error rates at the expense of long synchronization times. This paper examines the performance of a noncoherent SOQPSK detector which significantly improves the signal acquisition times without impacting BER performance in the AWGN environment. The two detection methods are also compared in their ability to combat other channel impairments, such as adjacent and on-channel interference.
    • PERFORMANCE OF UNITARY SPACE TIME CODES GENERATED BY GIVENS ROTATION MATRICES IN MULTIPLE-INPUT,MULTIPLEOUTPUT COMMUNICATION CHANNELS

      Kosbar, Kurt; Stanley, Seth; University of Missouri (International Foundation for Telemetering, 2007-10)
      Multiple-Input, Multiple-Output (MIMO) communication systems promise to provide significantly higher data rates at no increase in transmitted power or bandwidth. Unfortunately it is challenging to locate space-time codes which achieve these gains. It was recently shown that codes based on Givens Rotation Matrices (GRM) out perform many of the more conventional space-time codes at extreme values of signal to noise ratio (SNR). This paper investigates the performance of GRM codes over a wider range of SNR, to determine their usefulness in MIMO applications of interest to the telemetry community.
    • PLASMA DENSITY REDUCTION USING ELECTROMAGNETIC E×B FIELD DURING REENTRY FLIGHT

      Kim, Minkwan; Keidar, Michael; Boyd, Iain D.; Morris, David; University of Michigan; ElectroDynamic Applications Inc. (International Foundation for Telemetering, 2007-10)
      As a vehicle reenters or flies at hypersonic speed through the atmosphere, the surrounding air is shock heated and becomes weakly ionized. The plasma layer thus formed causes a communication problem known as ‘radio blackout’. At sufficiently dense plasma conditions, the plasma layer either reflects or attenuates radio wave communications to and from the vehicle. In this paper, we propose an electromagnetic field configuration as a method to allow communication through the plasma layer. Theoretical models show that this may address the blackout problem under a range of conditions. Preliminary experimental results are also presented.
    • QUALITY OF SERVICE PARAMETERS WITHIN A MIXED NETWORK FOR THE INET ENVIRONMENT

      Dean, Richard; Chaney, Antwan; Morgan State University (International Foundation for Telemetering, 2007-10)
      The focus of the integrated Network Enhanced Telemetry (iNET) project is to enhance the current telemetry technology (IRIG106) and still maintain the reliability of the current technology. The Mixed Networking environment is composed of a wired network based on standard 802.11 and a modified wireless based on 802.11. Determining the viability of the networking scheme within the iNET project is critical. The QoS features such as delay and jitter are measures of performance specified by user conditions. These QoS features are measured against current legacy links. This paper will show a comparison of the three QoS levels (best effort, assured, and premium services) that the network provides and investigate QoS performance of the Mixed Network in the iNET environment. This will provide a framework for assessing the strength and weakness of the Mixed Network as well as scoping further research.
    • RANGE COMMANDER’S COUNCIL (RCC) TELECOMMUNICATIONS AND TIMING GROUP (TTG) UPDATE ON TM OVER IP STANDARD DEVELOPMENT

      Eslinger, Brian; Kovach, Bob; TYBRIN Corporation; Superior Access Solutions (SAS) (International Foundation for Telemetering, 2007-10)
      The RCC TTG initiated task TT-49 to generate a standard for the transport of serial streaming telemetry (TM) over the Internet Protocol (IP). An ad hoc committee was activated comprised of Range and vendor participation to develop this standard. This paper will address the progress of the standard, the use of commercial standards, and the benefits to the ranges. The early meetings focused on developing the packet structure; the preliminary results will be presented along with the latest status on the RCC approval cycle.
    • RANGE SAFETY CASE STUDY: WESTERN RANGE CENTRALIZED TELEMETRY PROCESSING SYSTEM (WR CTPS), A LARGE DISTRIBUTED GROUND SYSTEM

      Mather, Jonathan; Shaw, Nancy; L-3 Communications Telemetry-West; Lockheed Martin Corporation (International Foundation for Telemetering, 2007-10)
      This paper presents a case study of the Western Range Centralized Telemetry Processing Subsystem (WR CTPS). This system was developed by Lockheed Martin Integrated Systems and Global Services and L-3 Communications Telemetry-West as part of the Range Standardization and Automation (RSA) IIA program. Requirements included real-time simultaneous acquisition of 16 PCM streams at rates of up to 30M bits per second; real-time processing; and data display on workstations connected over a gigabit Ethernet network. This system is designed for range safety and needs to be fault-tolerant while maintaining 100 percent data availability in the event of a single failure during an operation. The development of such a system demanded a rigorous Systems Engineering approach to ensure the successful upgrade and deployment onto the range infrastructure. This case study provides an overview of the system technical requirements and its architecture. The summary presents challenges encountered during the development and lessons learned while meeting them.
    • REORDERING PACKET BASED DATA IN REAL-TIME DATA ACQUISITION SYSTEMS

      Kilpatrick, Stephen; Rasche, Galen; Cunningham, Chris; Moodie, Myron; Abbott, Ben; Southwest Research Institute (International Foundation for Telemetering, 2007-10)
      Ubiquitous internet protocol (IP) hardware has reached performance and capability levels that allow its use in data collection and real-time processing applications. Recent development experience with IP-based airborne data acquisition systems has shown that the open, pre-existing IP tools, standards, and capabilities support this form of distribution and sharing of data quite nicely, especially when combined with IP multicast. Unfortunately, the packet based nature of our approach also posed some problems that required special handling to achieve performance requirements. We have developed methods and algorithms for the filtering, selecting, and retiming problems associated with packet-based systems and present our approach in this paper.
    • A ROADMAP TO STANDARDIZING THE IRIG 106 CHAPTER 10 COMPLIANT DATA FILTERING AND OVERWRITNG SOFTWARE PROCESS

      Berard, Alfredo; Manning, Dennis; Kim, Jeong Min; Eglin Air Force Base (International Foundation for Telemetering, 2007-10)
      High speed digital recorders have revolutionized the way Major Range and Test Facility Bases collect instrumentation data. One challenge facing these organizations is the need for a validated process for the separation of specific data channels and/or data from multiplexed recordings. Several organizations within Eglin Air Force Base have joined forces to establish the requirements and validate a software process compliant with the IRIG-106 Chapter 10 Digital Recording Standard (which defines allowable media access, data packetization, and error controls mechanics). This paper describes a roadmap to standardizing the process to produce this software process, Data Overwriting and Filtering Application (DOFA).
    • ROBUST ADAPTIVE BEAMFORMING WITH BROAD NULLS

      Yudong, He; Xianghua, Yang; Jie, Zhou; Banghua, Zhou; Beibei, Shao; Tsinghua University; China Academy of Engineering Physics (International Foundation for Telemetering, 2007-10)
      Robust adaptive beamforming using worst-case performance optimization is developed in recent years. It had good performance against array response errors, but it cannot reject strong interferences. In this paper, we propose a scheme for robust adaptive beamforming with broad nulls to reject strong interferences. We add a quadratic constraint to suppress the power of the array response over a spatial region of the interferences. The optimal weighting vector is then obtained by minimizing the power of the array output subject to quadratic constrains on the desired signal and interferences, respectively. We derive the formulations for the optimization problem and solve it efficiently using Newton recursive algorithm. Numerical examples are presented to compare the performances of the robust adaptive beamforming with no null constrains, sharp nulls and broad nulls. The results show its powerful ability to reject strong interferences.
    • SCALABLE LOW COMPLEXITY CODER FOR HIGH RESOLUTION AIRBORNE VIDEO

      Marcellin, Michael W.; Bilgin, Ali; Lalgudi, Hariharan G.; Marcellin, Michael W.; Bilgin, Ali; Nadar, Mariappan S.; University of Arizona; Siemens Corporate Research (International Foundation for Telemetering, 2007-10)
      Real-time transmission of airborne images to a ground station is highly desirable in many telemetering applications. Such transmission is often through an error prone, time varying wireless channel, possibly under jamming conditions. Hence, a fast, efficient, scalable, and error resilient image compression scheme is vital to realize the full potential of airborne reconnaisance. JPEG2000, the current international standard for image compression, offers most of these features. However, the computational complexity of JPEG2000 limits its use in some applications. Thus, we present a scalable low complexity coder (SLCC) that possesses many desirable features of JPEG2000, yet having high throughput.
    • SERIALLY CONCATENATED HIGH RATE CONVOLUTIONAL CODES WITH CONTINUOUS PHASE MODULATION

      Perrins, Erik; Damodaran, Kanagaraj; University of Kansas (International Foundation for Telemetering, 2007-10)
      We propose serially concatenated convolutional codes with continuous phase modulation for aeronautical telemetry. Such a concatenated code has an outer encoder whose code words are permuted by an interleaver, and a modulation, which is viewed as a code and takes the interleaved words as its input and produces the modulated signal. Since bandwidth expansion is a concern when coding is introduced, we focus on high rate punctured codes of rates 2/3 through 9/10. These are obtained by puncturing the basic rate 1/2 convolutional codes with maximal free distance. At the receiver end we use a reduced complexity iterative decoding algorithm which is essentially a soft input soft output decoding algorithm. These simple highly powerful concatenated codes produce high coding gains with minimum bandwidth expansion.