• 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.
    • SIMPLIFIED 2-state Detectors for SOQPSK-TG and SOQPSK-MIL

      Perrins, Erik; Kumaraswamy, Balachandra; University of Kansas (International Foundation for Telemetering, 2007-10)
      We study simple trellis-based detectors for SOQPSK that have a minimal level of complexity. In particular, we show that the state complexity can be cut in half relative to previous approaches—from 4 states down to 2—with asymptotically optimum performance. We give two possible means of achieving this: the pulse amplitude modulation (PAM) technique and the pulse truncation (PT) technique; both of these techniques make use of recent advances in SOQPSK technology based on a continuous phase modulation (CPM) interpretation of SOQPSK. The proposed simplifications are significant since trellis-based SOQPSK detectors are 1–2 dB superior to widely-deployed symbol-by-symbol detectors. These performance gains come at the expense of complexity, and the proposed 2-state detectors minimize this expense. Thus, these simple detection schemes are applicable in settings where high-performance and low complexity are needed to meet restrictions on power consumption and cost.
    • SOFT RECOVERY RECORDING SYSTEM FOR INTERIOR AND EXTERIOR BALLISTICS CHARACTERIZATION

      Guevara, Mauricio; Flyash, Boris; Army Research Development and Engineering Center (International Foundation for Telemetering, 2007-10)
      The US ARMY, ARDEC; in cooperation with AMCOM AMRDEC, Missile Guidance and Engineering Directorates; the Office of Naval Research; Naval Surface Fire Support; and the Naval Surface Weapon Center, requires multiphase development of a common, low-cost, high G survivable, high accuracy, Micro Electro-Mechanical Systems (MEMS) Inertial Measurement Unit (IMU) and Common, Deeply Integrated, Guidance and Navigation Unit (DI-GNU) for DoD gun launched guided munition and missile applications. The challenge for the Precision Munition Instrumentation Division (PMID) was to develop a Telemetry System to record the interior and exterior ballistics of a M831 TP-T projectile, which will be used as a carrier for soft recovery testing of IMUs and GNUs. This valuable data that would help The Government and contractors develop and validate multiple MEMS IMU design efforts, culminating with live fire verification performance test of pre-production in the Army’s 155-mm Soft Recovery Vehicle (SRVs) and missiles airframes.
    • STOPPING LAUNCH PAD DELAYS, LAUNCH FAILURES, SATELLITE INFANT MORTALITIES AND ON ORBIT SATELLITE FAILURES USING TELEMETRY PROGNOSTIC TECHNOLOGY

      Losik, Len (International Foundation for Telemetering, 2007-10)
      Telemetry Prognostics is Failure Prediction using telemetry for launch vehicle and satellite space flight equipment to stop launch failures, launch pad delays, satellite infant mortalities and satellite on orbit failures. This technology characterizes telemetry behaviors that are latent, transient, and go undetected by the most experienced engineering personnel and software diagnostic tools during integration and test, launch operations and on orbit activities stopping launch pad delays, launch failures, infant mortalities and on orbit failures. Telemetry prognostics yield a technology with state-of-the-art innovative techniques for determining critical on-board equipment remaining useful life taking into account system states, attitude reorientations, equipment usage patterns, failure modes and piece part failure characteristics to increase the reliability, usability, serviceability, availability and safety of our nation’s space systems.
    • STUDY ON GPS RECEIVER ALGORITHMS FOR SUPPRESSION OF NARROWBAND INTERFERENCE

      Yongkang, Hu; Qishan, Zhang; Yanhong, Kou; Dongkai, Yang; Beihang University (International Foundation for Telemetering, 2007-10)
      Despite the inherent resistance to narrowband signal interference afforded by GPS spread spectrum modulation, the low level of GPS signals makes them susceptible to narrowband interference. This paper discusses the application of a pre-correlation adaptive temporal filter for stationary and nonstationary narrowband interference suppression. Various adaptive algorithms are studied and implemented. Comparison of the convergence and tracking behavior of various algorithms is made.
    • The Sum-Rate Capacity of a Cognitive Multiple Access Sensor Network

      Panagos, Adam; Kosbar, Kurt; Dynetic, Inc.; University of Missouri (International Foundation for Telemetering, 2007-10)
      This paper investigates the sum-rate capacity of a cognitive multiple access (MAC) sensor network. The multiple access network consists of K sensors communicating to a common base station. Outside of the network exists another user of the radio spectrum. Each sensor of the MAC network is aware (i.e. cognitive) of this user, denoted the primary user, and transmits in a manner to avoid any interference to this user. No interference transmission is achieved using the dirty-paper coding technique. The sum-rate capacity is the theoretical maximum of the sum of the simultaneously achievable rates of each sensor within the network. Using a recently derived iterative algorithm, we quantify the sum-rate capacity of this network and investigate its behavior as a function of the number of sensors, cognitive signal-to-noise ratio (CSNR) and primary SNR (PSNR) in a Rayleigh fading environment. We also derive bounds and scaling results for the ergodic sum-rate capacity.
    • SYMBOL TIMING RECOVERY FOR SOQPSK

      Perrins, Erik; Chandran, Prashanth; University of Kansas (International Foundation for Telemetering, 2007-10)
      Shaped offset quadrature phase shift keying (SOQPSK) is a highly bandwidth efficient modulation technique used widely in military and aeronautical telemetry standards. It can be classified as a form of continuous phase modulation (CPM), but its major distinction from other CPM schemes is that it has a constrained (correlated) ternary data alphabet. CPM-based detection models for SOQPSK have been developed only recently. One roadblock standing in the way of these detectors being adopted is that existing symbol timing recovery techniques for CPM are not always applicable since the data symbols are correlated. We investigate the performance of one CPM-based timing error detector (TED) that can be used with SOQPSK, and apply it to the versions of SOQPSK used in military (MIL-STD SOQPSK) and telemetry group (SOQPSK-TG) standards. We derive the theoretical performance limits on the accuracy of timing recovery for SOQPSK, as given by the modified Cramer-Rao bound (MCRB), and show that the proposed TED performs close to these bounds in computer simulations and is free of false-lock points. We also show that the proposed scheme outperforms a non-data aided TED that was recently developed for SOQPSK. These results show that the proposed scheme has great promise in a wide range of applications due to its low complexity, strong performance, and lack of false-lock points.
    • TCP PERFORMANCE ENHANCEMENT OVER IRIDIUM

      Torgerson, Leigh; Hutcherson, Joseph; McKelvey, James; California Institute of Technology (International Foundation for Telemetering, 2007-10)
      In support of iNET maturation, NASA-JPL has collaborated with NASA-Dryden to develop, test and demonstrate an over-the-horizon vehicle-to-ground networking capability, using Iridium as the vehicle-to-ground communications link for relaying critical vehicle telemetry. To ensure reliability concerns are met, the Space Communications Protocol Standards (SCPS) transport protocol was investigated for its performance characteristics in this environment. In particular, the SCPS-TP software performance was compared to that of the standard Transmission Control Protocol (TCP) over the Internet Protocol (IP). This paper will report on the results of this work.
    • TECHNOLOGY CONVERGENCE: OBSERVATIONS ON TRANSITIONAL APPROACHES FOR DATA ACQUISITION IN A TCP/IP ENVIRONMENT

      Weir, Malcolm; Ampex Data Systems, Inc. (International Foundation for Telemetering, 2007-10)
      This paper discusses how IRIG 106 Chapter 10 recording techniques could be employed in a network-centric environment, while maintaining as many of the strengths of the traditional approach. In the course of that discussion, aspects of the published standard which would have to be disregarded or reinterpreted for a network-centric approach to be adopted are illustrated.