Kujiraoka, Scott R.; De Vries, James M.; Naval Air Warfare Center (International Foundation for Telemetering, 1998-10)
      The available space for the mounting of antennas on missiles and airborne targets is very limited. The vehicle integrator is constantly striving for smaller antenna apertures while requiring increased performance. Microstrip antennas with moderate dielectric loading have been successfully utilized in the past to meet these requirements. With the advent of high dielectric substrate materials, the designer now has the option of further reducing the size of the antenna while preserving the most desirable performance attributes. An example of the size reduction achievable with the new substrate materials is presented along with performance characteristics.
    • Reed-Solomon Coding as a Multipath Fading Countermeasure for PCM/FM Aeronautical Telemetry

      Rice, Michael D.; Friend, Daniel H.; Brigham Young University (International Foundation for Telemetering, 1998-10)
      This paper evaluates the use of Reed-Solomon error correcting codes as a countermeasure for the bursty errors caused by multipath fading seen in aeronautical telemetry channels. The tradeoff between code rate and interleaving depth is analyzed and an equation for predicting the code rate given a fixed burst length and interleaving depth is presented. Close agreement is found between predictions made by this equation and simulated results.

      Willis, James; L-3 Communications (International Foundation for Telemetering, 1998-10)
      Universal acceptance of the Windows NT operating system has made utilization of the personal computer (PC) platform for critical space operations a reality. The software attributes of the operating system allow PC products to attain the reliability necessary for secure control of on-orbit assets. Not only is the software more reliable, it supports better networking interfaces at higher speeds. The software upgrades that the Microsoft Corporation generates on a regular basis allow PCs to offer capabilities previously available only with UNIX-based solutions. As technology matures, PCs will operate faster, offer more graphical user interfaces, and give customers a lower cost versus performance choice. These reasons, and others to be discussed further, clearly demonstrate that PCs will soon take their place at the forefront of mission-critical ground station applications.

      Briggs, James R.; Youssef, Ahmed H.; Edwards Air Force Base (International Foundation for Telemetering, 1998-10)
      Optical trackers are often used at the Air Force Flight Test Center (AFFTC) and at other Department of Defense (DoD) ranges to collect video and trajectory data for real-time display and postflight processing. When optical trackers are used in remote areas, pointing data from radar is utilized to enable the trackers to initially acquire targets. To enable the trackers to use radar-pointing data, offsets to true north must first be known. This offset is taken into account given the current position of the optical tracker. During postflight processing, when determining the trajectory of the target, the offsets are also taken into account to produce an accurate trajectory solution. Current methods of determining offsets to true north are time consuming and involve a lot of guesswork. Typically, a map and a known landmark are used to determine the offsets to true north. Another method is to look for the North Star (Polaris) and input an estimated offset. This paper will describe an inexpensive, stand-alone system that utilizes the Global Positioning System (GPS) to determine these offsets. This device may be modified and integrated with other systems that may need to point accurately. For example, a gun barrel on a tank may need to point accurately to within a degree. This device may also be used to accurately position telemetry antennas.
    • Selling Telemetry Data Over the Internet Using SET

      Kalibjian, Jeffrey R.; CounterSign Software, Inc. (International Foundation for Telemetering, 1998-10)
      Over the past two years the design and implementation of secure Internet based data sharing tools which could enable geographically remote contractor teams to access flight and test telemetry data securely over the Internet were presented [1] [2]. Key technologies facilitating these capabilities were the Hypertext Transfer (HTTP) protocol , the Secure Sockets Layer (SSL) protocol, and the Secure Multipurpose Internet Mail Extension (S/MIME) specification . This year we discuss utilizing the Secure Electronic Transaction (SET) specification in tandem with HTTP, SSL, and S/MIME to deploy a system for securely selling telemetry data over the Internet.

      O’Cull, Douglas; Microdyne Corporation (International Foundation for Telemetering, 1998-10)
      This paper discusses modifications made to a commercial-off-the-shelf (COTS) signal generator that aids acquisition of low earth orbit (LEO) satellites. The modification compensates for the Doppler Frequency offset that commonly affects acquisition of LEO satellites. This allows the user to use a COTS signal generator for the uplink exciter. User programmable features have been added to the signal generator, which compensates for the Doppler Shift.
    • So You Think Tape is Dead

      Smith, Darren C.; Tenderholt, Dean; Naval Air Warfare Center - Weapons Division; Edwards Air Force Base (International Foundation for Telemetering, 1998-10)
      The times that we live in offers the most advanced pace of technology development ever known to the world, and it is getting faster. A large part of commercial computer technology development is based on increased size and decreased cost of memory devices, from which the instrumentation community can derive great benefit through the development of solid state systems. The procurement cost of new solid state systems utilizing increased memory capability makes the temptation to move to this technology unavoidable. There are, however, some issues that need to be discussed which go beyond procurement costs and involve operational and life cycle considerations.

      O’Donnell, John; AYDIN Telemetry (International Foundation for Telemetering, 1998-10)
      There are well-known advantages in using pseudo-random sequences for testing of data communication links. The sequences, also called pseudo-noise (PN) sequences, approximate random data very well, especially for sequences thousands of bits long. They are easy to generate and are widely used for bit error rate testing because it is easy to synchronize a slave pattern generator to a received PN stream for bit-by-bit comparison. There are other aspects of PN sequences, however, that are not as widely known or applied. This paper points out how some of the less familiar characteristics of PN sequences can be put to practical use in the design of a Digital Test Set and other specialbuilt test equipment used for checkout of the EOS AM-1 Space Data Receiver. The paper also shows how knowledge of these PN sequence characteristics can simplify troubleshooting the digital sections in the Space Data Receiver. Finally, the paper addresses the sufficiency of PN data testing in characterizing the performance of a receiver/data recovery system.

      Zhao, Xianming; Yang, Mingji; Zhou, Tingxian; Meng, Liqun; Harbin Institute of Technology (International Foundation for Telemetering, 1998-10)
      This paper analyzes the pseudo-random characteristic of m-sequence and proposes a spread spectrum communication scheme in which the phase-shifting sequences of msequence can be used as the spread spectrum code under given condition. Therefore, the available spread spectrum code set is expanded. It is theoretically proved that there are some advantages in using phase-shifting sequences instead of the conventional msequences or GOLD-sequences in spread spectrum communication system.

      Scofield, Don; Powell, Dave; Naval Air Warfare Center Weapons Division (International Foundation for Telemetering, 1998-10)
      The Joint Advanced Missile Instrumentation (JAMI) Program, a multi-year CTEIP effort, will develop an integrated instrumentation package for tri-Service small missile test and training applications. JAMI will provide telemetry, time-space-position information (TSPI), flight termination and end-game vector scoring in a low-cost, modular package that will allow world-wide test and training, thereby eliminating, in most cases, the need for range-specific (or multi-system) facilities. JAMI will incorporate GPS-based technology as the TSPI and vector scoring engine, as well as state-of-the-art telemetry. JAMI will also address the feasibility of a solid state programmable safe-and-arm device. The effort will include a Test Technology Development and Demonstration (TTD&D) risk reduction phase which will validate tri-service requirements, provide a technology demonstration, and assess the applicability of advanced antenna technology. This paper discusses the progress of the program during the TTD&D phase including preliminary testing of GPS receivers and conformal GPS antennas.

      Boulinguez, Marc; Carlier, Pierre-Marie; ENERTEC (International Foundation for Telemetering, 1998-10)
      Designed for unattended 24 hours-a-day operation in automatic system environments, the 3801 TT&C Digital Processor Unit is the key communication unit for ground stations operating spacecraft, from integration to positioning phase and in-orbit operation. Its architecture and technology concept combine high performance, compactness and modularity. The 3801 TT&C Digital Processor Unit supports multiple formats in a single stand-alone chassis, and incorporates extensive interfacing and functional provisions to maximize effectiveness, reliability and dependability. It supports a number of configurations for satellite control applications and performs :* • Telemetry IF demodulation and transmission of data to a high-level communication interface, with time tagging and display of decommutated parameters, • Command generation, with FSK or PSK and FM or PM modulation at 70 MHz, • Ranging measurements and calibration using ESA, INTELSAT and major standards (tones and codes). In addition, the 3801 TT&C Digital Processor supports a Synchronous Command Generator for spinning satellite in a single stand-alone chassis and includes : • FM signal discrimination, for satellite spin reference information coming from the Telemetry Reception channel, • Synchronization Controller for providing the reference « top » for the transmission of the synchronous tones, • Tones Generation of frequency tones towards the PM/FM Modulator.
    • TCP/IP Remote Control of a Ground Station

      Massey, Dale P.; Universal Space Network, Inc. (International Foundation for Telemetering, 1998-10)
      Satellite tracking ground stations are under continuous pressure to automate. Autonomy is generally the desired goal, but if the ground stations are in a Commercial Ground Network(CGN) setup to support many missions simultaneously, remote control of such stations is of much more importance. The proliferation of Low Earth Orbiting (LEO) science, earth resources and eventually global communications satellites either in orbit or planned, requires a much lower cost methodology for ground support. A CGN of TCP/IP remotely controlled ground stations lowers much of the manpower that was historically required to operate such stations. This paper will cover the remote control aspects needed for a satellite ground tracking station and offer a unique remote control topology utilizing TCP/IP.

      Voudouris, Thanos; NASA (International Foundation for Telemetering, 1998-10)
      This paper discusses the evolution of the ground satellite communication systems and the efforts made by the Goddard Space Flight Center's (GSFC) Advanced Architectures and Automation (AAA) branch, Code 588 to bring satellite scientific data to the user’s desktop. Primarily, it describes the next generation desktop system, its architecture and processing capabilities, which provide autonomous high-performance telemetry acquisition at the lowest possible cost. It also discusses the planning processes and the applicability of new technologies for communication needs in the next century. The paper is presented in terms simple for those not very familiar with current space programs to understand.

      Honglin, Yang; Yonghui, Yang; Xinan Electronic Engineering Institute (International Foundation for Telemetering, 1998-10)
      This paper describes the technology on transmitting a single super fast waveform signal in real-time and introduces the general situation of the telemetry transmitter in vehicle. The equipment is a FM system in view of RF frequency, it is a pulse system in view of RF power. This equipment can transfer not only super fast waveform signals but also slowly varying conventional telemetry signals. The design is very novel. It is a multi-usage telemetry transmitter in vehicle.

      Nasta, Rodolphe; ALCATEL ESPACE (International Foundation for Telemetering, 1998-10)
      This paper gives an overview on Telemetry, Tracking and Command (TTC) sub-system that are used onboard some telecommunication satellites. Then, a description of the equipments of such a sub-system is given, together with the main performances.

      Haddock, Paul C.; New Mexico State University (International Foundation for Telemetering, 1998-10)
      This paper discusses the design, configuration, and operation of a satellite station built for the Center for Space Telemetering and Telecommunications Laboratory in the Klipsch School of Electrical and Computer Engineering Engineering at New Mexico State University (NMSU). This satellite station consists of a computer-controlled antenna tracking system, 2m/70cm transceiver, satellite tracking software, and a demodulator. The satellite station receives satellite telemetry, allows for voice communications, and will be used in future classes. Currently this satellite station is receiving telemetry from an amateur radio satellite, UoSAT-OSCAR-11. Amateur radio satellites are referred to as Orbiting Satellites Carrying Amateur Radio (OSCAR) satellites.

      Reighter, Greg; Whiteman Air Force Base (International Foundation for Telemetering, 1998-10)
      Instrumenting the operational B-2 Strategic Bomber presents some unique problems. For example, the requirement to remain operational dictates that the aircraft must retain its stealth characteristics. This means traditional antennas cannot simply be attached to the airframe. A solution to this problem is an antenna designed with stealth, or Low Observable (LO), attributes. Stealth is not an absolute; it is relative. Therefore, antenna design becomes a balancing act between the LO relativity, antenna directivity, and antenna gain. Weapons testing is an additional concern, where instrumented ordinances transmit data that must be monitored real-time prior to launch. Stealth vehicles must carry weapons internally, restricting the Radio Frequency (RF) transmission of telemetered data from the weapon. With the development of future stealthy conveyances, such as the F-22, Joint Strike Fighter (JSF), ground, and ocean-going craft, these concerns will become even more prevalent.

      Schooley, L.C.; Chyr, Y-H.; Jordan, M.; Hagedorn, M.; Han, B.; Pat, J.; Ting, S.; Trotman, T.; University of Canterbury (International Foundation for Telemetering, 1998-10)
      This paper was prepared as part of the team design competition for a graduate level course given at the University of Canterbury, in Christchurch, New Zealand. It presents a high level design of a bobsled data acquisition system which is intended to aid athletes and coaches in achieving the maximum benefit from their time at the bobsled track. The system will measure every applicable aspect of the bobsled’s performance down the track, and provide real time and near real time feedback for the athletes and the coach. This system implements an inertial navigation and position system, monitors wind speed, measures the drivers steering input and effort, measures individual pushing effort in the critical start stage of the run, and provides cue signals to the runners when to mount the sled. A robust packet format and error correction in conjunction with a E2ROM backup system ensure data integrity. The data is transmitted utilising a GMSK signalling scheme, operating at a frequency of 400MHz. A space conserving patch antenna is mounted on the bobsled and a leaky wave antenna placed alongside the track for the transmission system. A link budget and the error performance of the transmission system are analysed. A graphical front end at the coach’s base station provides real time data display and analysis.

      Yates, James William; L-3 Communications (International Foundation for Telemetering, 1998-10)
      Current changes in the way that large flight test systems are utilized have affected the industry’s methodology in both the early design phases and in the implementation of nextgeneration hardware and software. The reduction of available RF spectrum, the implementation of packet telemetry methods and systems, and a desire to implement commercial-off-the-shelf (COTS) hardware are only some of the considerations that telemetry systems integrators and product houses have to face. This paper describes how test methodology changes affect current large systems design at both government test ranges and at airframe/missile manufacturer test facilities. In addition, consideration is given to the area of increased processing power as it affects hardware and software design, the leveraging of such current and future telecommunications technology as network switch technology and compression, cross utilization, standardized technology, and the movement toward platform-independent software.

      Hordeski, Theodore J.,Jr.; GDP Space Systems (International Foundation for Telemetering, 1998-10)
      The telemetry and aerospace communities require communications equipment providing various modulation and demodulation formats. One format, with application in Space Ground Link Subsystems (SGLS), utilizes a Ternary (tri-tone) Frequency Shift-Keyed (FSK) signal Amplitude Modulated (AM) by a triangle waveform. Historically, SGLS equipment has operated with a fixed tri-tone frequency set (e.g., 65 kHz, 76 kHz and 95 kHz). The need for additional transmission channels and increased bandwidth efficiency creates the requirement for equipment with the flexibility to generate and receive varied and higher frequency tone sets. Combining analog and digital techniques, GDP Space Systems has developed the FDT001. It is an FSK/AM detector which recovers a bit rate clock at one of four selectable bit rates and reproduces ternary FSK modulation data over a widely tunable range of tone frequencies. The tuning range is expanded by using two methods of digital frequency discrimination. The following paper describes the design of the FDT001.