• International Telemetering Conference Proceedings, Volume 54 (2018)

      Unknown author (International Foundation for Telemetering, 2018-11)

      Thurston, Noah; Vanhoy, Garrett; Bose, Tamal; Univ Arizona, Dept Elect & Comp Engn (International Foundation for Telemetering, 2018-11)
      The threat of a malicious user interfering with network traffic so as to deny access to resources is an inherent vulnerability of wireless networks. To combat this threat, physical layer waveforms that are resilient to interference are used to relay critical traffic. These waveforms are designed to make it difficult for a malicious user to both deny access to network resources and avoid detection. If a malicious user has perfect knowledge of the waveform being used, it can avoid detection and deny network throughput, but this knowledge is naturally limited in practice. In this work, the threat of a malicious user that can implicitly learn the nature of the waveform being used simply by observing reactions to its behavior is analyzed and potential mitigation techniques are discussed. The results show that using recurrent neural networks to implement deep Q-learning, a malicious user can converge on an optimal interference policy that simultaneously minimizes the potential for it to be detected and maximizes its impediment on network traffic.

      Lipina, Jacob; Van Horn, Andrew; Schad, Judah; Kosbar, Kurt; Missouri University of Science and Technology (International Foundation for Telemetering, 2018-11)
      This paper discusses the applications of a wireless telemetry module used to collect remote sensor data used in a teleoperated electric vehicle that competed in the 2018 Mars University Rover Challenge (URC). Remote wireless soil sensor pods, 100 cc in volume, equipped with a 32-bit microcontroller and embedded IEEE 802.11 b/g/n Wi-Fi were distributed at key locations to relay soil moisture and temperature values over a local repeater to a remote base station. Combined with a low power deep sleep mode (1.84 mW), two 2500 mAh lithium-ion polymer batteries, and voltage regulation electronics, such a device could periodically relay telemetry data for many years without recharge. The small size presents the opportunity for large scale production and distribution across exoplanetary surfaces for monitoring soil characteristics over time.

      Keshmiri, Shawn; Hauptman, Dustin; Shukla, Daksh; Blevins, Aaron; University of Kansas, Electrical Engineering & Computer Science Department; University of Kansas, Department of Aerospace Engineering (International Foundation for Telemetering, 2018-11)
      Swarms of autonomous unmanned aerial systems (UASs) are becoming increasingly popular as efficient replacement for manned aircraft. The major component that makes the swarm of UASs possible is an efficient exchange of aircrafts states (e.g. position & velocity) for all agents and the ground station. Advanced communication technologies are required to be implemented on each agent to enable real-time communication at high frequencies (e.g. 20 Hz) to avoid inter collisions and holding formations. To assess mesh network limitations and to identify bottlenecks, a series of simulations are carried out using actual hardware that is used for swarms of UASs, which are: (1) Amount of bandwidth that can be guaranteed given the communication system being used (XBee-900HP), each plane that the KU team uses, transmits 127 variables, 4 bytes each, at 20 Hz which means each plane needs 10 KBps and the mesh network might be able to support 53 UASs theoretically (2) Range limitations (3) Latency issues.

      Brown, Jason R.; Rohrer, Justin P.; Naval Postgraduate School, Department of Computer Science (International Foundation for Telemetering, 2018-11)
      Drone swarms pose a particular challenge to telemetry networks, due to the number of airborne nodes involved, and their potential to overwhelm the available bandwidth on the communications channel with simultaneous telemetry streams. Previously, we saw that mobile ad-hoc (MANET) routing protocols could exacerbate this issue by flooding the network with routing-control packets. In this work we model the Naval Postgraduate School fixed-wing drone swarm and compare the performance of several disruption-tolerant networking (DTN) routing protocols designed to address these challenges.

      Teku, Noel; Bose, Tamal; Univ Arizona, Dept Elect & Comp Engn (International Foundation for Telemetering, 2018-11)
      In the High Frequency (HF) band, ranging from 3-30 MHz, long-range communications can be obtained by bouncing signals off the ionosphere without any significant infrastructure. However, the ionosphere changes rapidly, which can cause potentially harmful effects to the transmitted signal. This has motivated research into using adaptive equalization in this band to reverse these effects. However, a disadvantage of this technique is that based on the equalizer model and learning algorithm used, the error propagation may become significantly large, resulting in insufficient equalization to respond to these variations. To counter this, we investigate the usage of cognitive equalization, where an adaptive equalizer is equipped with the ability to change its structure (i.e. number of taps, step size, etc.) based on the current channel conditions and use probability of error to characterize its performance.
    • Telemetry System Based on MESH Network and Its Application

      Guo, Pingfan; Liu, Ming; Li, Hong; Zhu, Hongxiang; Chinese Flight Test Establishment (International Foundation for Telemetering, 2018-11)
      In the flight test, the advantages of network telemetry have gradually emerged, and their application fields will also be expanded. This paper introduces a network telemetry system based on MESH net and its application in flight test, a ground station can receive telemetry signals of several planes at the same time; the components and functions of the system are described, the advantages of this network telemetry system, existing problems and suggestions on future improvements are presented.

      Willis, Jacob; Holtom, Jacob; Walton, Patrick; Smith, Jackson; Wallin, Nikolai; Long, David G.; BYU, Department of Electrical and Computer Engineering (International Foundation for Telemetering, 2018-11)
      An elegant telemetry payload, which transmits IMU, atmospheric, or light data during flight and deployment from a small model rocket, is presented. Data is received by a custom, mobile, handpointed ground station. The payload is patterned after a thumb-sized satellite, called a femtosat. Its design is optimized for ease of implementation. The femtosat system resulted from a grassroots, student peer-mentoring program developed at Brigham Young University.
    • The Design and Application of C-band Base Station Based Multi-target Telemetry Network System

      Shiwei, Guo; Zhongjie, Wang; Xin, Zhang; Zhaohui, Huo; Chinese Flight Test Establishment (International Foundation for Telemetering, 2018-11)
      A C-band base station based multi-target telemetry network system for flight test is designed in this paper. The requirements of multi-target transmission are realized by TDMA and TDD technology. And the transmission rate of up to 50 Mbps is provided by the high efficient modulation method. An integrated air-to-ground telemetry network is built with C-band wireless two-way link. The telemetry signals of super large airspace are covered seamlessly through multiple base stations, therefore the shortage of current telemetry is solved, and the demand of multi-target and mass date transmission for flight test is satisfied. The development of the system provides technical support for the high speed data transmission of the flight test, which will lay a foundation for the construction of integrated air-to-ground test and the test network system.

      Rozsa, Jace; Averett, Tyler; Killpack, Marc; Rice, Michael; Brigham Young University (International Foundation for Telemetering, 2018-11)
      This paper describes the design and performance of the BYU mars rover with an emphasis on the wireless communications system and the transmission and reception of data vital to the performance of the rover.

      Painter, Michael K.; Madanagopal, Karthic; Swaminathan, Kannan; Jones, Charles H.; Knowledge Based Systems, Inc.; C. H. Jones Consulting, LLC (International Foundation for Telemetering, 2018-11)
      There continues to be growing pressure to sell off spectrum currently allocated for defense purposes in favor of private sector applications, prompting concerns that we will soon reach a point where Department of Defense (DoD) needs can no longer be met. In response, the Range Commanders Council (RCC) Frequency Management Group (FMG) developed a baseline set of standard metrics to measure spectrum utilization, demand, efficiency, and operational effectiveness. Using this standard (RCC 707-14) as a foundation, a Spectrum Management Metrics Toolkit (SMMT) has been developed to calculate, plot, and display these metrics. The challenge now is leveraging these metrics to inform and construct the arguments needed to maintain access to needed spectrum. The purpose of this paper is to describe progress toward the development of a methodology and a set of analytics based on the RCC standard to build such a compelling narrative. The methodology is based on a data analytics and communication concept, called “Story Points,” which seeks to guide users in the discovery, composition, and delivery of targeted narratives and supporting graphics derived through mining available data sources.
    • Research on Embedded Real-time Processing Technology of ARINC429 Bus Dynamic Logic Block

      Qi, Shengyuan; Wang, Zhongjie; Shi, Fenglei; Qi, Xiaopeng; China Flight Test Establishment (International Foundation for Telemetering, 2018-11)
      ARINC429 bus is widely used. In a new type of logic block communication method, the logic layer of the application layer is composed of a plurality of ARINC429 messages, and the message length and content dynamically change. The telemetry monitoring needs real-time analysis of the application layer communication protocol to correctly interpret the user-defined message content. This paper proposes an embedded real-time processing scheme, which integrates real-time processing hardware and software in data acquisition unit. It can dynamic analysis the application layer protocol of the logic block, extract user-defined information according to the telemetry for downloading, the problems encountered in telemetry monitoring of the type of communication are solved. At the same time, this solution is also applicable to real-time analysis of other avionics bus in the application layer protocols.

      Buxton, Jonas; Thomure, Logan; Downs, Roger; Bosanko, Garrett; Kosbar, Kurt; Missouri University of Science and Technology (International Foundation for Telemetering, 2018-11)
      Robotic systems that operate indoors are often unable to rely on GPS, and dynamic environments prove difficult to navigate for robotic systems that rely on SLAM (Simultaneous Location and Mapping). Autonomous navigation without the use of GPS or SLAM techniques require a system to rely on more fundamental hardware and software concepts. The challenge is made even greater when the system is intended to fly, interact with moving targets, and avoid moving obstacles. This is the design criteria that our autonomous multirotor is adhering to for the International Aerial Robotics Competition. This paper will describe the purpose behind each of our multirotor's sensors, such as LIDAR (Light Detection and Ranging) systems and Optical Flow sensors, that enable it to accurately interact with its environment without SLAM techniques, as well as the multirotor's onboard software that powers its autonomous capabilities.
    • A New Network Telemetry technique In Aviatic Flight Tests

      Xingguo, Zhang; Hong, Li; Guojin, Peng; Zanchao, Wang; Chinese Flight Test Establishment (International Foundation for Telemetering, 2018-11)
      In order to address the issue of insufficient telemetry frequencies in flight tests, a telemetry transmission solution is proposed to transmit the principal parameters and HUD video for multiple aircrafts based on bi-directional wireless network. All the key points including the wireless transmission architecture for airborne and ground integration, network resources management, and dynamic configuration of airborne test system are illustrated. The research result has been verified in flight tests, and the experimental methods and results are presented as well.

      Alam, Tasmeer; Moazzami, Farzad; Dean, Richard; Morgan State University, Department of Electrical and Computer Engineering (International Foundation for Telemetering, 2018-11)
      This paper includes the design, modeling and analysis of the aeronautical channel which includes the dynamics of flight simulation. For any given flight path scenario in the cruise state it is well understood that the channel is fitted by a 2 ray model. The dynamics of this model can be generated using the two-ray ground reflection model which is based on the position, velocity, and direction of the aircraft. The dynamic aeronautical channel model includes Doppler shift and delay spread for each path of a channel model. This paper shows how each parameter is created for modelling the dynamic channel. The design of such channel model will help the telemetry community to incorporate channel dynamics in computer simulation to improve the accuracy of flight simulation in the design and pre-test stages. Further, it can provide insight to the selection of modulation, equalization and coding for such channels.

      Madon, Phiroz H.; Young, Tom; O’Brien, Thomas; Radke, Mark; Vencore Labs Development Team; Test Resource Management Center (International Foundation for Telemetering, 2018-11)
      DoD test ranges are experiencing ever-expanding needs for air-to-ground telemetry bandwidth, and hence are under pressure to manage the telemetry spectrum resource with high efficiency. The Spectrum Management System (SMS) provides test range operations staff with advanced tools for frequency de-confliction and air-to-ground RF link quality prediction for upcoming test flights. Additional features of the system include: automated, algorithmbased frequency de-confliction and assignment; record-keeping and automated archiving of frequency assignments, to be used for spectrum defense; 3-D GIS terrain-based coverage maps, displaying predicted air-to-ground link quality in each part of upcoming flights; determination of opportunities for frequencies reuse. Innovations include: addressing the combinatorial NP-hard problem of frequency assignment by applying multiple real-world constraints in a specified order; using a spectrum white space closest-fit algorithm to minimize spectrum fragmentation; creating space-time-frequency quanta in the database to store RF emissions for rapidly-moving aircraft.

      Schmalz, Daniel; Lennon, Joseph; Wang, Enkuang; Brothers, Timothy; Georgia Tech Research Institute (International Foundation for Telemetering, 2018-11)
      This paper examines the real-time implementation of equalization techniques. Telemetry RF channels are formidable due to the nature of desert test ranges – specifically due to multipath, changing path loss from environmental effects, and thermal distortions. This challenge is further complicated by the high velocity nature of test assets. Optimization of channel equalization in a real-time scenario is essential for high speed data telemetry over extended distances. This paper examines the mathematical background of equalization techniques and presents results based on FPGA implementations. The results were obtained from Vivado High Level Synthesis (HLS), which generates HDL from C/C++, as well as traditional VHDL coding. The contribution to the state of the art in this paper is the determination of the technological maturity of HLS versus traditional hand coding and the comparison of FPGA implementations of equalization algorithms against current platforms.

      Peken, Ture; Tandon, Ravi; Bose, Tamal; Univ Arizona (International Foundation for Telemetering, 2018-11)
      Massive multiple-input multiple-output (MIMO) technology has recently gained a lot of at- tention as a candidate technology for the next generation wireless systems. With a higher number of antennas, pilot-based channel estimation faces a limitation in the number of or- thogonal pilots to be used among users in all cells. Sparse channel estimation by using regularization methods can reduce the pilots compared to pilot-based channel estimation. In this paper, we study two regularization methods: least absolute shrinkage and selection operator (lasso) and elastic net. We investigate the performance of least squares (LS), lasso, and elastic net when the sparsity of the channel changes over time. We study the optimum tuning parameters for lasso and elastic net based channel estimators to achieve the best performance with the di erent number of pilots and values of signal-to-noise ratio (SNR). Finally, we present the asymptotic analysis of LS, lasso, and elastic net based channel esti- mators.

      Kovach, Bob; IPtec, Inc. (International Foundation for Telemetering, 2018-11)
      The efforts to implement the distribution of real-time information streams via IP packet-based networks in the range environment have largely utilized the recovery of timing information via implicit techniques, such as adaptive clock recovery. These techniques allowed the alignment of streams with disparate delay characteristics to accuracies on the order of 1 millisecond. With the availability of techniques to distribute high accuracy timing information to network nodes, the capability to recover and align real time streams on the order of microseconds is possible. This paper will focus on a methodology to perform precision stream alignment that utilizes timestamping and the IEEE 1588 Precision Time Protocol (PTP) as a clock source. IEEE 1588 is currently utilized in cellular networks to deliver synchronization to remote network elements, providing superior accuracy and stability. The paper will review expectations for performance and discuss considerations in system level design to optimize timing distribution performance and ultimately stream alignment accuracy. System elements and their effect on performance will be identified and characterized. Finally, a TM Gateway implementation example which utilizes PTP coupled with hardwareassisted timestamping techniques to align recovered TM streams to a high degree of accuracy will be described. Real world results for clock accuracy and expectations for stream alignment accuracy will be shared.

      Norland, Kyle; Marcellin, Michael W.; Univ Arizona, Dept Syst & Ind Engn (International Foundation for Telemetering, 2018-11)
      To address the challenge of avoiding dynamic obstacles during the course of the 2018 SUAS competition, a multistage obstacle characterization and avoidance algorithm was designed and implemented. The obstacle characterization section begins with simple base assumptions about behavior and goes through several more advanced stages of obstacle characterization and prediction as more data arises and advanced behavior is detected. The path finding section of the algorithm uses a recursive Monte Carlo path sampling function with a flexible structure that allows for usage with varying computational budgets. It also restricts its computational usage depending on the level of variability in the obstacles.