Peterson, Dwight M.; Fleet Analysis Center (International Foundation for Telemetering, 1982-09)
      Telemetered data generated by missile systems has become increasingly complex with the inclusion of asynchronous data streams, variable word lengths, and discrete encoding. The display of this data for analysis purposes requires sophisticated equipment, usually designed with a programmable architecture. This paper describes software support that was developed for a stored program PCM decommutator. The software includes a cross assembler and supports downline loading of the decommutator from a host computer.

      Hoagland, J.C.; Rockwell International (International Foundation for Telemetering, 1982-09)
      During operational space flight, the communications and telemetry subsystem of the Space Shuttle orbiter uses S-band and Ku-band links to provide, in addition to tracking, reception of digitized-voice, commands, and printed or diagrammatic data at a maximum rate of 216 kilobits per second (kbps). The subsystem also provides a transmission capability for digitized voice, telemetry, television, and data at a maximum rate of 50 megabits per second (mbps). S-band links may be established directly with a ground station and both S-band and Ku-band links may be routed through The National Aeronautics and Space Administration (NASA) tracking and data relay satellite system (TDRSS). A simultaneous capability to communicate with other satellites or spacecraft, using a variety of formats and modulation techniques on more than 850 S-band channels, is provided. Ultra-high frequency (UHF) is used for communication with extravehicular astronauts as well as for a backup subsystem for state vector update. Audio and television subsystems serve on-board needs as well as interfacing with the radio frequency (RF) equipment. During aerodynamic flight following entry, the S-band link can be supplemented or replaced by a UHF link that provides two-way simplex voice communication with air traffic control facilities.

      Shingledecker, D. K.; Hughes Aircraft Company (International Foundation for Telemetering, 1982-09)
      The Space Shuttle Orbiter’s Ku-band integrated radar and communications subsystem will function in its radar role during satellite rendezvous. As a radar the Ku-band subsystem searches for, acquires, and then tracks targets. In the track mode, the radar outputs measured range, range-rate, angle, and angle-rate values to both the Orbiter’s general purpose computer (GPC) and the astronaut’s Ku-band subsystem control panel. This data is used to navigate the Orbiter to its satellite rendezvous. The radar is integrated with the Ku-band communications function and thus achieves reduction in weight and volume compared with separate subsystems for each function. This paper provides a user oriented description of the radar subsystem. Topics to be covered are radar requirements, modes of operation, and system configuration.

      Zelon, Michael; Space Transportation & Systems Group Rockwell International (International Foundation for Telemetering, 1982-09)
      The payload interrogator (PI) for communication between the orbiter and detached DOD/NASA payloads is described. Salient features of the PI are discussed, including its capabilities and limitations. For compatible operation in the orbiter’s electromagnetic environment, the PI is equipped with a dual triplexer assembly. A limiter diode circuitry allows the PI to be safely exposed to high effective isotropic radiated power (EIRP) payloads at close range. A dual conversion PM short-loop receiver has a sufficient dynamic range for undistorted reception of near and distant payload signals. The PI acquires signals from compatible transponders within ±112 kHz of its center frequency. The center frequency can be set at 125-kHz steps for the spaceflight tracking and data network (STDN), 370 kHz for the deep space network (DSN), and 5 MHz for the space satellite control facility (SCF). The PI has falselock- on protection capability to accommodate reliable acquisition of standard NASA and DOD payload transponders. The wideband phase detector demodulates baseband information, and by the use of AGC, provides three independent constant-level data outputs. Each of the 861 frequency channels is generated instantaneously by the receiver and transmitter synthesizers. The PM-modulated RF carrier transfers command information to the detached payloads. The RF output power is adjustable to assure reliable communication with payloads of various sensitivities (G/T). A wide and narrow carrier sweep capability is provided to accommodate any frequency uncertainty of payloads. The transmitter has an ON-OFF modulation control to avoid false-lock-on problems. The PSP command input modulation index is fixed, while the modulation index for the PS is a function of the input voltage. The PI receiver’s complementary transmit channels are spaced 115 kHz for STDN, 341 kHz for DSN, and 4 MHz for SCF. The PI is compatible with the orbiter’s configuration control equipment—GCIL, the PSP and PS for I/O data transfer, the Ku-band subsystem for “bent pipe” baseband telemetry transmission to ground, the MDM for the PI’s telemetry transfer, and the RHCP/LHCP antenna subsystem. Overall PI capabilities and limitations for communication with unique payloads are also presented.

      Brown, Roger W.; McDonnell Douglas Astronautics Company (International Foundation for Telemetering, 1982-09)
      This paper will demonstrate a computer application program to predict the spectral shape and IRIG-RF bandwidth required for a PCM/FM telemetry system. A filtered PCM bit stream is constructed from a Fourier series and used to FM-modulate the RF carrier. The Fourier transform of the FM-wave is calculated numerically, and voltage amplitude levels are plotted on a Tektronix graphic display. Several PCM bit patterns are used and a composite display is formed to approximate an actual PCM/FM spectrum. A comparison of predicted and actual spectra will be presented.

      Tan, Harry H.; University of California (International Foundation for Telemetering, 1982-09)
      The complete statistical behavior of the random gain of a photomultiplier tube (PMT) has not previously yielded to exact analysis. In this paper a Markov diffusion model is used to determine an approximate probability density for the random gain. This approximate density preserves the correct second order statistics and appears to be in reasonably good agreement with previously reported experimental data. The error performance of a simple binary direct detection optical communication system is analyzed using this density.

      Kelly, Mike; Sangamo Weston, Schlumberger (International Foundation for Telemetering, 1982-09)
      This purpose of this paper is to show how structured programming methodologies, used in the design and development of computer programs, can and should be used in the design and development of telemetry systems. One important concept presented in that of thinking of the telemetry system as a complete system from the very beginning such that a total system design can evolve “naturally”. Many of the problems associated with telemetry systems today are due to the fact that the various “pieces” of the system were designed independently and without regard for each other. Also discussed are the various levels of documentation produced along with Engineering and Marketing responsibilities as they relate to systems design.

      Kroger, Marlin G.; Palos Verdes Estates (International Foundation for Telemetering, 1982-09)
      This paper addresses the development of an architecture or framework to guide the design of future communications links and networks to support tactical military operations. In the next decade military forces are planned to be much more mobile and dispersed than they are today. Improved sensors and information processing capabilities will provide information needed to manage defense actions against numerically superior enemy forces, but the effective use of that information will require greatly improved communications capability. The resultant digital information traffic which consists of bursts of data between and among users and data sources must be accomodated efficiently, something that neither the present circuit-switches nor the current store-and-forward message transmission systems do well. Also, there is a requirement for much more interoperability between the systems of different services and nations. Internetwork routing of data transmissions can provide more robust connectivity via alternate paths, to cope with jamming and physical attacks on specific transmission media or nodes. An approach to data network interconnection structure that has emerged over the past several years is the concept of a hierarchial set of protocol layers, each one building on the one below. In total, they constitute a reference model for “open systems interconnection.” The most common version of such a reference model is the International Organization for Standardization’s reference model of Open Systems Interconnection (ISO OSI) (1). The ISO OSI model has been designed to serve the fixed plant, benign-environment commercial user. DoD has special needs for security, precedence, internetwork data transfer and user mobility that are not yet reflected in the ISO model. Because of these special needs candidate DoD models that are different from the ISO model have been proposed. However, an important consideration in the choice of or development of a DoD standard is that DoD Systems should be able to use commercial equipment and interface with commercial data networks. Also a consideration is that the reference model used for strategic and tactical communications should be a standard throughout DoD, although specific protocols could differ as necessary to support tactical vs. strategic needs. In total, these requirements and considerations constitute a significant design challenge that must be addressed promptly if DoD is to have any influence on the finalization of the ISO OSI model to get it to accomodate DoD requirements as much as possible.

      Hahn, Jacob C.; Rockwell International (International Foundation for Telemetering, 1982-09)
      Data from the Space Shuttle is recorded on magnetic tape during manufacture, during pre-flight tests and during flight. Thus a permanent record is obtained for all tests. When a tape recorder suddenly stops before the end of its run, some data will not be recorded. Tape recorders run silently and make no sound when they stop. A tape recorder that is not running is easily observed, but constant visual monitoring is impractical. Yet it is important that personnel become aware of the problem at once. An audio alarm that sounds when a tape recorder stops before the end of its run will alert personnel. An alarm in use at Rockwell’s Flight Systems Laboratories not only sounds when a tape recorder stops before it is supposed to, but it turns on a standby recorder in less than two seconds.

      EMANUEL, DAVID A.; The Aerospace Corporation (International Foundation for Telemetering, 1982-09)
      This paper addresses the technology advances in S-band remote satellite tracking station hardware which have occurred in the last twenty years. Significant progress has been made in increasing performance, decreasing size, weight and power consumption and greatly improving reliability. Standard remote control interfaces and built-in test/diagnostic features along with readily available control processors can provide automated remote control at modest cost thereby permitting site manning to be reduced significantly and still provide high system availability.
    • Telemetering Standards Coordination Commitee

      Jennings, Vernon A. (International Foundation for Telemetering, 1982-09)

      Daniel, Jack T.; Jones, Gary P.; E-Systems Inc., ECI Division (International Foundation for Telemetering, 1982-09)
      Evolving growth in Navy ship-to-air missile design has resulted in a need for larger quantities of telemetry information with increasing emphasis on digital telemetry. This has inherently led to the requirement for telemetry processing equipment that is adaptable to these changing missile telemetry data formats. The design for the Telemetry Recording and Reduction Equipment (TRRE), that incorporates today’s technology into a compact, realtime analysis tool for shipboard use, is presented in this paper. The TRRE was designed to process both the Pulse Amplitude Modulation (PAM) telemetry data formats of existing missile designs and the Pulse Code Modulation (PCM) data formats of evolving missile designs. The TRRE design minimizes the required operator interace through preprogrammed telemeter formats and programmable decommutation tables. A microprocessor is utilized in the design to program the decommutation hardware configuration.

      Feng, Ju; Beijing Institute of Aeronautics and Astronautics (International Foundation for Telemetering, 1982-09)
      A telemetry system based on Walsh functions has been developed since 1980.[1.2] The systerm is called sequency division multiplex, or SDM. A prototype of the system hss been assembled and a lot of laboratory tests are also made in recent 2 or 3 years. Of course, in order to put this system into real use, some practical problems still remain to be solved. In this paper the system design measures taken to improve the accuracy and some new a snchronization methods we adopted are described. Since the choice of subcarriers is very important in designing a telemetry system, a table of recommended sequence values of the walsh functions for subcarriers of the telemetry system is presented. Since the vibration signal in high frequency band is produced in many cases, it is necessary to build a system which can measure this signal. The frequency response of each channel is 2000 Hz , it will have wide applications in industrial automation.

      Radomsky, Israel; Hochman, D.; Israel Military Industries (International Foundation for Telemetering, 1982-09)
      The Israel Military Industries (IMI), Systems Division, has had requirements for telemetry systems and measurements techniques to obtain data regarding projectiles performance in-flight and in-bore. This paper presents a brief description of a new programmble PCM telemetry system which employs several novel techniques like flexible multiplexing, programmable signal conditioner on a channel per channel basis for multiple gains and offsets), and a miniature size due to thick film hybrid construction and all thses along with very high shock survivability and long term reliability. This paper also presents a description of a very low cost telemetry package for measuring the in-flight spin rate using a specially designed transmitting antenna, a telemetry package for measuring event type phenomena and analog data (acceleration, pressure, strains, etc.) while the projectile is traveling in-bore. Examples of data obtained during actual firings are presented and discussed.

      Hedeman, Walter R., Jr. (International Foundation for Telemetering, 1982-09)
      The locus of recording when using IRIG standard bias methods is deduced from data on phase distortion presented by the author at ITC 1972. Contrary to popular opinion recording does not occur at the trailing edge of the record gap. At the maximum depth of recording it takes place near the center of the record gap, and in the surface layers next the record head approximately one half the record gap length past the trailing edge of the record gap.

      McMullen, Malcolm; Assistant Vice President-Advanced Planning Space Communications Company (International Foundation for Telemetering, 1982-09)
      The Tracking and Data Relay Satellite System (TDRSS) is approaching launch readiness, with operations scheduled to commence in 1983. This paper describes TDRSS including the commercial communications or Advanced Westar (AW) components and the launch, network, and test elements being employed to bring the system to operational readiness for user support. Users and user equipment are also discussed.

      Johnson, F. Bruce; Colorado Video, Inc. (International Foundation for Telemetering, 1982-09)
      This paper presents a method for synchronous conversion of infra -red image data to a Pulse-Code Modulation (PCM) bit stream for recording on instrumentation tape recorders. The PCM data recording method provides an improvement over analog FM recording in signal to noise ratio, horizontal resolution, and speed of data formatting. The methodology was applied to the design of a PCM encoder for an AGA model 680 Thermovision camera. The extension of the design to other devices is discussed. Considerations for the display of real-time and reduced speed data display on conventional television monitors are presented.

      Sullivan, James F.; Ford Aerospace & Communications Corporation (International Foundation for Telemetering, 1982-09)
      Recent policy statements from senior Air Force personnel places a high priority on the survivability of “deliverable products” from space systems, throughout the conflict spectrum. The timely delivery of these products is dependent on the endurability of the spacecraft, the bit-stream carrying the products, and the ground terminals. Transportable/Mobile Terminals afford a viable option to provide a control segment that can be balanced with the endurability of the space and user segments. This paper examines Transportable/Mobile Terminals whose mission is to provide tracking, telemetry and command support to mission satellites through the conflict spectrum. The role and relationship of TMT’s in the totality of the Satellite Command and Control architecture is discussed in an operational, as well as technical, context. Topics of discussion include threats and countermeasures, sensitivity of design to requirements, the impact of satellite autonomy and the relationship of TMT’s to other planned improvements to the Satellite Command and Control architecture.

      Lasken, Walter W.; Rockwell International (International Foundation for Telemetering, 1982-09)
      This paper presents an overview of the various types of uplink commands available for attached or detached payloads and discusses in detail the manner in which the Space Shuttle orbiter common set and stand-alone computers accept and process these commands. Command and data processing within the orbiter systems during ascent and on-orbit operation are also discussed. The uplink command formats, as they relate to the data processing system, are presented in some detail.
    • Utilization of Fiber Optics in Large Scale Landline Telemetry Systems

      Saulsberry, Garen J.; Willis, James L.; New Mexico State University (International Foundation for Telemetering, 1982-09)
      The large-scale landline telemetry system may benefit from the application of fiber optics. With present technology, practical means exist to design, implement, and test longdistance, data-transmission systems using fiber optics. Fiber optics and Computer Automated Measurement and Control (CAMA) equipment provide application and tradeoff advantages over a hard-wire system. Procedures for equipment verification must be developed to confirm and verify system performance of the design criteria. Practical computations may be made using values representative of actual system performance. A solution is provided to a typical data transmission problem.