PARKHANI, BHARAT; TAYLOR, PAUL R. (International Foundation for Telemetering, 1991-11)
      Application of new and modern technology to Fire Control Systems (FCS) requires qualification through extensive simulated testing followed by field testing. This paper addresses application of a telemetry preprocessor in a real time closed loop test system, for testing an anti-aircraft tank FCS. A predefined and preprogrammed test sequence loaded into the preprocessor allows it to accept measurement data and return processed stimuli data in real time to various units in the loop. An acquisition and display subsystem consisting of a host computer and workstation allows data archiving and quicklook displays to check data integrity. Interactive operator and/or programmable control of test sequencing permits system flexibility. Ultimate usage as a test set for verification of function, performance and accuracy in a production environment would give the user a test platform which provides productivity improvement.

      Murphey, Robert A.; Eglin Air Force Base, Florida (International Foundation for Telemetering, 1991-11)
      This paper describes the progress made by the Wright Laboratory Armament Directorate Instrumentation Branch in developing Subminiature Instrumentation Technologies. These advancements will be explained relative to the overall scope of Subminiature Instrumentation efforts. The goal of these efforts is a DoD depot capability to provide low cost, non-intrusive telemetry instrumentation for any weapon system.
    • Subcarrier Placement in a PCM-FM-FM/FM Modulation Scheme

      Moser, Juliette Lyn; New Mexico State University (International Foundation for Telemetering, 1991-11)
      In a PCM-FM-FM/FM modulation scheme, one pulse code modulated (PCM) signal is added to a series of FM subcarrier modulated signals, and the sum is modulated on one FM carrier frequency. After the signal is carrier demodulated at the receiver and the signals modulating the subcarriers are individually filtered and demodulated, the information carried by the subcarrier frequencies may be distorted or lost due to interference power of the PCM signal that is passed by the subcarrier signals’ bandpass filters. The effect of the interference power may be reduced when the subcarrier frequencies are chosen to coincide with the zero crossing frequencies of the PCM signal. It will be shown that this choice results in a lower interference power than when the subcarrier frequencies come between the zero crossings. The PCM signal used in this study is of polar nonreturn to zero format.

      Laufman, G.E.; Slivkoff, W.J.; Stanford Telecommunications, Inc. (International Foundation for Telemetering, 1991-11)
      A low cost Transportable Ground Station (TGS) for satellite tracking, Telemetry & control (TT&C) applications has been developed. The initial focus of the TGS is to provide S-Band Space-Ground-Link-Subsystem (SGLS) TT&C services for these satellites with compatible transponders. The TGS also has the capability to be expanded to perform mission control station tasks including telemetry data analysis, command formulation, mission analysis and satellite ephemeris generation. The TGS consists of an International Shipping Organization (ISO) shelter and a foldable 5 meter antenna both of which are mounted on a 48' commercial air ride trailer. The TGS size meets requirements for United States highway transportation. The TGS can also be transported via C-130 aircraft. A photograph of the TGS model is shown in Figures 1 and 2.

      Bisson, Kenneth J. (International Foundation for Telemetering, 1991-11)
      While the scientific press brims with descriptions of state-of-the-art projects using the latest technology to produce huge amounts of data, little attention is given to the system requirements that result when Terabytes of data are generated. This paper examines the affect on telemetry, and replay/analysis systems and the necessary integration of high-speed digital tape recorders in such systems. Specifically, it considers how the tape recorder interfaces to the computer system, how the interface is integrated into the computer’s I/O architecture, and how much the user can expect in performance.
    • A Useful Method of Error-Correction and Data Synthesis for Telemetry

      Chuan-hang, Fan; Xinan Electronic Engineering Institute, China (International Foundation for Telemetering, 1991-11)
      In the field of telemetry, data synthesis is an interesting problem for multi-beam and multi-receiver system. This paper introduces a useful method of coding and decoding for linear block code, and describes a decoding method of M repeatition codes---a special product code, the data synthesis is based on this method.

      Can, Ouyan; Chang-jie, Shi; Beijing Research Institute of Telemetry; Ministry of Aeronautics and Astronautics (International Foundation for Telemetering, 1991-11)
      The Multi-Stream Data-Driven Telemetry System (MSDDTS) is a new generation system in China developed by Beijing Research Institute of Telemetry (BRIT) for high bit rate, multi-stream data acquisition, processing and display. Features of the MSDDTS include: .Up to 4 data streams; .Data driven architecture; .Multi-processor for parallel processing; .Modular, Configurable, expandable and programmable; .Stand-along capability; .And, external control by host computer. This paper addresses three very important aspects of the MSDDTS. First, the system architecture is discussed. Second, three basic models of the system configuration are described. The third shows the future development of the system.

      Carden, Frank; New Mexico State University (International Foundation for Telemetering, 1991-11)
      Design parameters for a FM/FM telemetry system are determined in terms of the IRIG specifications for proportional bandwidth channels. Three mathematical models used by designers of the above processes are extended and compared. That is, FM multitone models are used to establish the relationship between frequency deviations, modulation indices, signal-to-noise and IF bandwidth for the IRIG channels. Since spectral efficiency and signal quality are of major importance, a goal of the design is to have a minimum IF bandwidth, while fixing as large as possible the values of the modulation indices for the subcarriers modulating the carrier in order to achieve as large as needed output signal-to-noise ratio.

      Morris, R.A.; Powell, W.R.; Bundick, S.N.; Scientific-Atlanta, Inc.; NASA/Goddard Space Flight Center (International Foundation for Telemetering, 1991-11)
      Changing mission requirements have forced NASA to procure a new generation of tracking telemetry system with performance and features greatly exceeding existing system capabilities in many areas. These requirements and the system that was designed to meet them are discussed. Initial results of system testing are presented.

      Feather, Bob; O’Brien, Michael; Loral Data Systems, Inc. (International Foundation for Telemetering, 1991-11)
      There have been many recent technological advances in small computers, graphics stations, and system networks. This has made it possible to build highly advanced distributed processing systems for telemetry data acquisition and processing. Presently there is a plethora of vendors marketing powerful new network workstation hardware and software products. Computer vendors are rapidly developing new products as new technology continues to emerge. It is becoming difficult to procure and install a new computer system before it has been made obsolete by a competitor or even the same vendor. If one purchases the best hardware and software products individually, the system can end up being composed of incompatible components from different vendors that do not operate as one integrated homogeneous system. If one uses only hardware and software from one vendor in order to simplify system integration, the system will be limited to only those products that the vendor chooses to develop. To truly take advantage of the rapidly advancing computer technology, today’s telemetry systems should be designed for an open systems environment. This paper defines an optimum open architecture system designed around industry wide standards for both hardware and software. This will allow for different vendor’s computers to operate in the same distributed networked system, and will allow software to be portable to the various computers and workstations in the system while maintaining the same user interface. The open architecture system allows for new products to be added as they become available to increase system performance and capability in a truly heterogeneous system environment.

      Gustin, Thomas W.; SYSTRAN Corp. (International Foundation for Telemetering, 1991-11)
      This paper presents an exciting new concept in real-time information distribution that can be easily integrated into existing and future telemetry reception and data dispersal systems. After briefly examining the evolutionary path and various perceptions of the concept “real-time”, a variety of techniques are explored in achieving the expedient movement of real-time information. Many non-telemetry application environments are now using real-time shared-memory networking techniques to obtain large, highspeed integrated sharing of common information. The phenomenal results are partially attributable to high reliability, extremely low latency, and ease of use. This paper attempts to present various telemetry applications and scenarios with descriptions of benefits achieved by simply changing existing data movement techniques to those using shared-memory networking techniques.
    • Software Development of a Standardized User Interface for the HAFB Telemetry Ground Station

      Seebold, Otto P., Jr.; Physical Science Laboratory (International Foundation for Telemetering, 1991-11)
      The Systems Development (SD) group at the Physical Science Laboratory (PSL) has developed and integrated many telemetry data acquisition systems for both government and non-government customers. PSL/SD normally only develops telemetry hardware when there is no commercially viable equipment available within the cost restraints of the contract. Over the years, PSL/SD has chosen the best commercially available hardware that fulfilled the requirements of the specific project. Each project presented a unique set of requirements that necessitated a custom designed user interface for the setup of each vendor’s telemetry hardware. PSL found that it was redeveloping the telemetry definition user interface for each vendor’s product and this was consuming a larger percentage of the development budget. Therefore, in the development of the user interface for Holloman Air Force Base (HAFB) Telemetry Processing System (TPS), PSL decided to develop a user interface that could be easily modified to support new telemetry hardware with a minimum effort and present a common user feel to all future telemetry systems.

      Bennett, Toby; Looney, Kristin; Chesney, Jim; NASA, Goddard Space Flight Center (International Foundation for Telemetering, 1991-11)
      Space telemetry data processing elements for flight and ground systems are currently developed using discrete components on a project-by-project basis. The adoption of various standards, such as those recommended by the Consultative Committee for Space Data Systems (CCSDS), brings commonality of requirements across future NASA communications elements and affords the opportunity to create standard components to meet these requirements. Over the past five years, NASA’s Goddard Space Flight Center (GSFC) has developed a series of high performance Very Large Scale Integration (VLSI) components for space data systems. These standard components have enabled the development of high performance data systems that are an order of magnitude more compact and cost effective than systems of the previous generation. Recent advances in design automation tools and integrated circuit densities have yielded the means to achieve yet another leap in the integration levels, performance and cost reduction of space data systems. Design automation tools can generate complex integrated circuit designs from high level technology independent functional descriptions. A single reusable functional description can be targeted to a variety of circuit technologies including CMOS, ECL and GaAs. With available densities of over 1 million integrated transistors in both CMOS and GaAs technologies, standard components integrating multiple processing elements are realizable for both flight and ground projects. This paper describes the ongoing efforts of the Microelectronics Systems Branch at GSFC to create highly integrated components to meet functions outlined by the CCSDS using design automation techniques.

      Law, Eugene L.; Pacific Missile Test Center (International Foundation for Telemetering, 1991-11)
      There is a requirement to digitize certain wide-band analog signals in telemetry applications. Typically, an analog-to-digital converter (ADC) with eight or more bits of resolution is used. The resulting signal requires a much larger transmission bandwidth than the original analog signal. The frequency domain information is of primary interest for many applications. In these cases, there are several methods for minimizing the transmitted bandwidth. One method is to perform fast fourier transforms (FFTs) on the signals and only transmit information about the largest signals. The disadvantages of this approach include: relatively long time delay before transmission, resolution bandwidth fixed when FFT performed (unless phase information is also transmitted), and extra complexity in the telemeter. This paper will discuss some effects of minimizing the transmitted bandwidth by quantizing to a small number of bits. The performance will also be compared with analog frequency modulation (FM). Measured performance will be presented for four different input signals and one-, three-, and eight-bit quantization. These signals are amplitude modulation, angle modulation, sum of sine waves, and frequency sweep. The test setup is shown in figure 1. The analyses presented in this paper were performed using either fast fourier transforms (FFTs) or a Kay DSP Sonagraph. The FFT length was 1024 points and a Hann (cosine) window was used. The analysis hardware used for these tests has an analog input, therefore, all digitized signals were converted to analog signals before analysis. The signals were low pass filtered before analysis to minimize aliasing in the analysis and display process.

      BORDAS, Jean-Claude; LEBLANC, Jean-François; ELECTRICITE DE FRANCE; SCHLUMBERGER Industries (International Foundation for Telemetering, 1991-11)
      For the last dozen years, ELECTRICITE DE FRANCE has been using a digital telematry system mountable on the rotors of its generating machines in case of acceptance tests or after technical hitch, under difficult environmental conditions (125 degrees C and centrifugal acceleration of 100,000 m/s ). This system, manufactured by 2 SCHLUMBERGER, has proved itself in many test programs on high-power electrical motors, primary pumps of PWR reactors, steam turbines, alternators, etc. Today, the need is growing towards operational monitoring of equipment. Using this type of equipment in a monitoring system is a greater challenge. In fact, it is necessary to obtain an MTBF longer than the fuel refilling period (approximately 18 months) to make significant savings in product costs. A technological upgrade of the existing product was undertaken in late 1989. A very effective product capable of meeting the needs expressed is now available on the market. The system can be used to build systems with 1 to 63 channels with pass-bands ranging from 250 Hz to 10 kHz and very high precision (approximately 0.1%), under the above-mentioned environmental conditions. Its size, low power consumption, range of operating temperatures (-20 to 125 degrees C), resolution (12 bits), adaptability and capability of operating under conditions of acceleration and vibrations (100,000 M/s and 1000 m/s from 20 to 1000 Hz), make it a 2 2 unique product of its type. Although designed for use on rotating machines, these devices, thanks to the designs and technologies used, are compatible with other types of applications. The central equipment is also modular, a change in the structure of the rotor-mounted system does not call any of the investments into question; only the equipment’s software configuration is modified. A full line of standard equipment for reception, decommutation, recording and processing is available. This paper is intended to show how this product was developed so as to meet the main constraints of a system mounted on rotating machines. Problems related to installation on the machine, the power supply to the system and data transmission are not dealt with here. A short video film will illustrate our analysis.

      JARYNOWSKI, ROBERT J.; New Mexico State University (International Foundation for Telemetering, 1991-11)
      A VME computer can be used to provide the basis for a telemetry data processing station. Using “off-the-shelf cards” the designer is able to build up a front end that meet several of the data processing requirements. The ease in interfacing to the VME bus also provides a convenient platform for the development of highly specialized interfaces requiring programmable control. The results are a low-cost highperformance system that is easily expandable as needs and/or technology grow. Based on this strategy, the Physical Science Laboratory (PSL) at New Mexico State University developed a multichannel high-speed analog-to-digital converter (ADC) assembly on a single VME board. The design approach used at PSL to develop the VME-based ADC is discussed in an effort to describe both developments in analog-to-digital conversion integrated circuits and the use of a VME CPU to control them for data processing purposes.

      Hoefener, Carl E. (International Foundation for Telemetering, 1991-11)
      As we develop more space vehicles, a pressing requirement emerges to provide precision tracking information. This need for exact time and space-position information (TSPI) persists whether developing and testing space weapons or locating the precise position of intelligence-gathering satellites. Because this is a worldwide tracking requirement, the use of conventional tracking techniques such as radar is precluded. Fortunately the Global Positioning System (GPS) is now in place and can provide the tracking information required. GPS offers two techniques for tracking space vehicles. A GPS receiver can be installed on the vehicle to determine the position that is then relayed to a ground terminal, or a GPS frequency translator can be used to compute the vehicle position at the master groundsite. Since both techniques have been proven satisfactory, the specific tracking requirement determines the method selected. For the flight tests of the Exoatmospheric Reentry-Vehicle Interceptor Subsystem (ERIS), the GPS frequency translator technique is used. A GPS frequency translator is installed on the target (a reentry-vehicle launched on a Minuteman from Vandenberg), and a translator is also installed on the ERIS, which is launched from Meck Island in the Kwajalein Atoll. The GPS frequency translator approach was chosen for these tests for a variety of reasons, the most important of which were the limited instrumentation space on the target and interceptor, the extreme dynamics of the interceptor, the tracking accuracy required, and the range at which the operation must be tracked. For the tracking of orbiting satellites, a GPS receiver can be flown on the satellite with its derived position information continuously stored. This data can then be dumped as the satellite passes over a selected groundsite.

      Parra, Mario Z.; McIntyre, Robert G. (International Foundation for Telemetering, 1991-11)
      The Office of the Under Secretary of Defense for Research and Engineering recognized the potential advantages of a GPS-based range tracking system. As a result, the Range Applications Joint Program Office (RAJPO) was established. (1)The RAJPO was formed to develop a family of NAVSTAR GPS range equipment for the tri-service national test range community. The Air Defense Artillery Test Directorate (ADATD) has supported the RAJPO in the potential use of GPS-derived time, space, and position information (TSPI) in operational testing environments.

      White, Joey; Policella, Joseph; CAE-Link Corporation (International Foundation for Telemetering, 1991-11)
      Telemetry and data communications network simulation training devices are used to train mission controllers and spacecraft flight crews to manage the space network’s resources for consistent and reliable data flow between a user’s spacecraft and control center. A Space Communication Network simulation for communication controller training contains models for; network configuration, resource scheduling, simulation of tracking data blocks, data quality monitoring (DQM), responses and interaction, malfunctions, and a communication environment to control the flow of data. The goal of the simulation is to train in the management of the Space Communication Network utilizing real-world formats and real-world protocols thus enabling the simulator to appear to the trainees as the real-world network.

      Netzer, Allan (International Foundation for Telemetering, 1991-11)
      The Air Force Flight Test Center (AFFTC), 6545th Test Group, is the Air Force center of expertise for Unmanned Air Vehicle (UAV) test and evaluation (T&E). To facilitate this mission, the 6545th Test Group developed three NC-130 Surrogate Carrier Launch Platform (SCLP) aircraft for UAV test support. The SCLP aircraft support various test functions including avionics testing, captive-carriage, and launch of UAVs and missiles. The system can support concept validation and early Developmental Test and Evaluation (DT&E) without requiring the operational launch platform, freeing these critical assets from test support. The SCLP aircraft use a palletized “roll-on/roll-off” approach to increase test support flexibility and decrease test costs. Capabilities include airborne command and control, flight termination, telemetry tracking, recording, relay of in-flight test vehicle data, and engineering test stations for airborne data analysis and test control. The SCLP can captive-carry, launch, and operate a test article out of line of sight of range ground stations. SCLP can display engineering data and relay the data to a Mission Control Center (MCC). Additionally, the SCLP permits autonomous operation on undeveloped airspace or supplements capabilities at existing facilities. Early SCLP configurations were used during concept validation of the air-launched Tacit Rainbow missile, while later variations supported several efforts, including classified programs. This paper describes the telemetry-tracking and relay capabilities of the SCLP using the Airborne Data Acquisition and Relay System (ADARS) station. The ADARS uses a combination of tracking and omni-directional antennas to acquire, track, record, and retransmit telemetry data. The combination of two directional tracking antennas and diversity combining of the received signals enables the system to reliably acquire test vehicle data at relatively low signal levels or with high fade rates. The system proved very versatile and was modified to support various special project requirements. The system is currently configured to receive and retransmit telemetry data up to a rate of 1.92 Megabits per second (Mbps).