Chi, Danny T.; Kodak Berkeley Research (International Foundation for Telemetering, 1990-11)
      Interleaving is a simple and effective way to improve the performance of an error correction scheme on a bursty channel. The interleaving of codewords will spread the effects of a long burst error into short bursts over several encoded sequences instead of a single codeword, and thus the chosen error correction scheme can correct them. This paper addresses a recently developed method, called helical interleaving ([1]) and presents some of its applications. The advantages of helical interleavers as compared with traditional interleavers are discussed. A relationship between helical interleavers and convolutional interleavers is also presented.

      Scoughton, Troy E.; Danford, Robert; New Mexico State University; Acroamatics (International Foundation for Telemetering, 1990-11)
      The system covered in this paper is the Telemetry Processing System (TPS) designed and installed for processing data acquired from high speed test sleds at Holloman AFB, NM. Because this facility operates as a test range, testing sleds from many different agencies for a variety of different purposes, prior knowledge is not always available concerning the instrumentation on the test sled to be used and therefore the type of data retrieval and processing required. The TPS must then be capable of acquiring and processing multiple data types including PAM and PDM, multiple FM streams (72 channels) and high speed PCM (4 channels) . Additionally, the requirement has been imposed for 3.2 Msample/sec analog-to-digital conversion capability for high resolution measurement of certain analog data (10 channels). When the above data are multiplexed with three time sources, eight channels of sled positional information and operated at maximum rate, the raw data exceed 15 Mbytes/sec. Depending on the scheme used to tag the samples, time stamp the data, and convert the data to engineering units, the processed data rate could have exceeded 100 Mbytes/sec and therefore the reasonable limit of existing telemetry processing technology. The TPS requires not only the capability to acquire and record this very high rate data, but also the realtime display of selected measurements. Further, the acquired data must be readily available immediately after the test for quick look evaluation, and for data selection for archival storage. This paper will explore the design process that allows the system to meet these requirements using mostly off-the-shelf or only slightly modified equipment by making clever compromises and effective use of stream separation. The paper will explore the hardware and software considerations which were examined and the solutions implemented in the final design. Development and integration of this system are currently underway, with delivery scheduled for later this year.

      Rice, William A.; Montano, William G.; White Sands Missile Range (International Foundation for Telemetering, 1990-11)
      This paper discusses the specific applications at White Sands Missile Range to certify the airborne telemetry packages, to receive, relay, and record Pulse Code Modulation (PCM) telemetry data. One of the most critical areas of data transmission throughout the Range is that of telemetry data. As digital data transmission becomes more commonplace, it becomes necessary to develop new methods for receiving, relaying, and recording digital telemetry data. A recent requirement to support reception, relay, record, and processing of a ten-megabit PCM telemetry signal drove the development of the system described in this paper. New receiving equipment was procured in order to handle the high bandwidth. Two new methods are now being used at White Sands Missile Range to relay high rate PCM data. - One is the Lightwave Fiber System. There are four telemetry lightwave links presently being used at WSMR: a multiple fiber link from the Master Relay Control Station (Jig-56) to the Telemetry Data Center (TDC), a duplex link between Jig-56 and Launch Complex 37, a simplex link from Chin Site to Jig-56 and a simplex link at Holloman Air Development Center. - The second method is the Digital Microwave Links from a TransportableTelemetry Acquisition and Relay System (TTARS) to Jig-67 and from Jig-67 to Jig-56.

      Liang, Yanxi; Dai, Lihong; Xian, Electro-Mechanical Information Technology Institute In China (International Foundation for Telemetering, 1990-11)
      With the speedy development of microelectronics and computer technology, there has arisen a particular memory telemetry branch in projectile telemetry area. Researches and experiments have been done a lot by telemetry communities in many countries. Various memory telemetry devices have been evolved for mutifarious application objects or purposes. The measurement of terminal environmental parameters is characterized by its ephemeral duration in which on-board system will undergo two, firing and impact, overloads, the latter, often reaching beyond 80,000g, is more severe than the former. Moreover, targets usually consist of such different materils as gravels, steel, or concrete, etc. In addition, the irregularity of these materits makes the mechanical conditions of the projectile penetrating into them a great deal more intricate. In order to measure the acceleration, the axial and tangential forces, the mechanism actions and the like of the parts of a fuze on impact, a high-g memory telemeter and accelerometer with an integrated operational amplifier have been developed. Field tests have also been carried out.

      Cipolla, Frank; Seck, Gerry; Datron Systems Inc. (International Foundation for Telemetering, 1990-11)
      Datron Systems Inc. has developed a high efficiency autotrack feed series which uses a tracking mode coupler to generate track error signals. The mode coupler allows the use of a corrugated feed horn in doubly shaped or cassegrain geometries or a scaler ring feed in prime focus reflectors, to achieve extremely high overall antenna efficiencies. The low insertion loss of the mode coupler allows the incorporation of autotrack capability in an antenna system without degradation of the overall G/T or EIRP. Another feature of this feed is the excellent cross talk performance. The mode coupler is a rho-theta type tracker and as such is suitable for use in both single channel monopulse and equivalent full three channel monopulse autotrack applications. Datron has built, installed, and tested feeds of this type at S, C, and X band frequencies and is currently under contract to develop a dual K/Q band version. Datron has also integrated other components into the mode coupler feed assembly such as: amplifiers, filters, diplexers, couplers, downconverters, switches, noise sources, etc.

      Quart, Barry; Mitchell, Rick; Bombardier Inc.; Loral Data Systems (International Foundation for Telemetering, 1990-11)
      The Data Acquisition System Ground Station (DASGS) is a system developed by Loral Data Systems (Loral) for CANADAIR Aerospace Group. The system implements the latest technologies in telemetry front-end equipment, host computers, networking, and graphic workstations. The goal of the DASGS is to supply Canadair with a telemetry acquisition and processing system that can satisfy the Regional Jet (RJ) program requirements and provide future expandability to service their needs throughout the 1990’s. This paper will address three aspects of this telemetry system. First, the telemetry data processing requirements of the RJ program will be described. Second, the system architecture, both hardware and software, will be discussed and the basis for the architecture. The third topic of this paper will cover how the system processing capability can be increased to satisfy Canadair’s future requirements.

      Miller, James J.; Tannenholz, Philip H.; Harley Industries, Inc. (International Foundation for Telemetering, 1990-11)
      Improved performance has been achieved in the new Herley design of the Model MD700C-1 Drone Tracking and Control System, C-band Command and Control Transponder. The approach for obtaining better radio frequency rejection, automatic gain control, local oscillator stability, and power supply efficiency is described. New hybrid microwave integrated circuit application techniques were used to design a small local oscillator, tunable over the 5400 to 5900 MHz range with a frequency drift of less than ± 1 MHz. This low frequency drift allowed the use of a 4 pole immediate amplifier filter, 60 dB down, at 40 MHz bandwidth, which, when coupled with the three cavity radio frequency preselector filter, provides 7 pole out of band rejection for unwanted radar signals operating at close frequencies. To augment the out of band rejection, a new form of 75 dB dynamic range automatic gain control was used, which combines signal attenuation with a circuit that reduces immediate frequency noise with increasing signal. This allows rejection of the radars own in-band multipath signals by reducing the gain and threshold sensitivity. To reduce power consumption and heat while operating over a wide voltage range, a switching mode regulator and a nonsaturating core power supply was designed to operate at 80% efficiency. Compared to units in field use over the past 10 years, the new design shows improvements of 400 percent in local oscillator frequency stability, 30 percent in out of band frequency rejection, 66 percent in the automatic gain control dynamic range, and 60 percent in power supply efficiency. The MD700C-1 was developed by Herley Industries for the USAF SMALC, and is currently in production.

      PEREIRA, CARLOS M.; US ARMAMENT RESEARCH, DEVELOPMENT AND ENGINEERING CENTER (International Foundation for Telemetering, 1990-11)
      Triboelectric phenomena occurs when static electricity accumulates on the surfaces of flying projectiles due to friction of air contaminants on the aerodynamic projectile surfaces. The sequence of events that create this phenomena indicate that as the projectile flies through the denser atmosphere, electric charges are transferred from the surface of the flying projectiles to the dust as a result of the collision with the atmospheric air stream. In the development of highly static sensitive electronic circuitry used in timing and fuzing, the need to know how the charge builds up has warranted the investigation of the triboelectric affects during flight. This paper will discuss the method of instrumentation used, the pre-flight test results obtained during dynamic wind tunnel tests, and the instrumentation system used to perform the triboelectric measurements.
    • An Integrated Real-Time Turbine Engine Flight Test System

      Moro, Mike; Friedman, Paul J.; Allied-Signal Aerospace Corporation; Loral Instrumentation (International Foundation for Telemetering, 1990-11)
      New developments and modifications to existing gas turbine engines require qualification through extensive ground testing followed by flight testing. An increasing work load necessitates productivity improvements in the test platform utilization and the telemetry ground station. This paper addresses the application of a compatible family of commercial offthe-shelf telemetry systems for quick-look to ensure data integrity on board the Boeing 720 test platform, and a distributed architecture ground station to serve multiple engineering disciplines through the use of an acquisition subsystem serving data to independent color graphics workstations via an Ethernet local area network.
    • An Integrated Workstation Environment for Operational Support of Satellite System Planning & Analysis

      Hamilton, Marvin J.; Sutton, Stewart A.; The Aerospace Corporation (International Foundation for Telemetering, 1990-11)
      This paper describes a prototype integrated environment, the Advanced Satellite Workstation (ASW), that has been developed and delivered for evaluation and operator feedback in an operational satellite control center. The current ASW hardware consists of a Sun Workstation and Macintosh II Workstation connected via an ethernet Network Hardware and Software, Laser Disk System, optical Storage System, and Telemetry Data File Interface. The central mission of ASW is to provide an intelligent decision support and training environment for operator/analysts of complex systems such as satellites. There have been many workstation implementations recently which incorporate graphical telemetry displays and expert systems. ASW is a considerably broader look at intelligent, integrated environments for decision support, based upon the premise that the central features of such an environment are intelligent data access and integrated toolsets. A variety of tools have been constructed in support of this prototype environment including: an automated pass planner for scheduling vehicle support activities, architectural modeler for hierarchical simulation and analysis of satellite vehicle subsystems, multimedia-based information systems that provide an intuitive and easily accessible interface to Orbit Operations Handbooks and other relevant support documentation, and a data analysis architecture that integrates user modifiable telemetry display systems, expert systems for background data analysis, and interfaces to the multimedia system via inter-process communication.

      Blasdel, Arthur N., Jr.; Hartman, Wayne; Ford Aerospace Corporation (International Foundation for Telemetering, 1990-11)
      Ford Aerospace Corporation has been working for several years on Independent Research and Development (IR&D) that brings artificial intelligence technology to bear on space mission operations tasks. During this time, we have developed a flexible and sophisticated tool, called Paragon, that supports knowledge representation in a very intuitive and easy to maintain manner. As a fallout of our knowledge representation approach in Paragon, we get a simulation capability that supports testing and verification of the model. This same capability can be used to support various space operations training and readiness activities (1). Recently, we became aware of the very flexible telemetry generation and display capabilities of the Loral 500 system, and found that we could combine our Paragon modeling and simulation capability with the Loral equipment to create an intelligent telemetry simulator that has the potential to dramatically reduce acquisition, development, installation, and maintenance costs for space system simulation. This paper discusses the features and capabilities of the Paragon/Loral 500 Intelligent Telemetry Simulator (ITS) as well as the prototyping we have accomplished to date.
    • International Telemetering Conference Proceedings, Volume 26 (1990)

      International Foundation for Telemetering, 1990-11

      Ng, Wai-Hung; Leung, Tony; The Aerospace Corporation (International Foundation for Telemetering, 1990-11)
      Recently, many satellite systems started to employ reflective-array compressor (RAC) to demodulate their M-FSK communication signals. Because the RAC’s time delay varies with the temperature, pilot-tones are usually introduced as the operational reference. In this paper, the basic chirp Fourier transform (CFT) is briefly reviewed. Then, investigation into possible pilot-tone interference caused by various chirp signals with RAC’s dispersive delay properties is presented and discussed.

      Tubbs, Casey; SCI Technology, Inc. (International Foundation for Telemetering, 1990-11)
      Asynchronous data sources such as those associated with Space Based Radar create a unique problem for Time Division Multiplexed (TDM) Pulse Code Modulation (PCM) frame formats. The problem consists of data arrival based on external occurrences such as target tracking, and not due to sampling polls from internal sequencers. Reserved time slots for asynchronous data must be provided within the synchronous TDM telemetry stream. This increases the required bandwidth to transfer collected data to ground sites proportional to the worst case arrival rate of asynchronous data and the maximum latency allowed for the application. Asynchronous data is readily handled by the Consultative Committee for Space Data Systems (CCSDS) recommended formats without the need to increase the bandwidth disproportionately. The recommendation maintains the ability to provide synchronous telemetry data collection and transmission provided by the TDM PCM frame formats. This paper provides an implementation of CCSDS recommendations and addresses the methodology of merging asynchronous and synchronous data sources without the prerequisite increase in bandwidth associated with purely synchronous TDM approaches. Additional implementation details are provided for the implementation of a Telemetry Operation Procedure (TOP) to downlink error free telemetry frames. The TOP is not currently supported within the CCSDS recommendation. The implementation is provided through the Micro Packaged Data Acquisition and Control Systems developed by SCI Technology in Huntsville, Alabama.

      PENHARLOW, DAVID; AYDIN VECTOR DIVISION (International Foundation for Telemetering, 1990-11)
      The new generation of advanced tactical aircraft and missiles places unique demands on the electronic and mechanical designs for flight test instrumentation, high bit rates, operating temperature range and system interconnect wiring requirements. This paper describes a microminiature PCM distributed data acquisition system with integral signal conditioning (MMSC) which has been used in advanced aircraft and missile flight testing. The MMSC system is constructed from microminiature, stackable modules which allow the user to reconfigure the system as the requirements change. A second system is also described which uses the same circuitry in hermetic hybrid packages on plug-in circuit boards.

      Malone, Erle W.; Breedlove, Phillip; Boeing Aerospace, Seattle, WA; Loral Conic, San Diego, CA (International Foundation for Telemetering, 1990-11)
      A telemetry system which integrates MIL-STD-1553 bus data, dual-simplex bus data, vehicle performance data, and environmental sensor data multiplexing involves many interfacing constraints. The engineering design considerations and hardware constraints required to implement this system are presented in this paper.

      Vander Stoep, Donald R.; Ball Systems Engineering Division, San Diego, CA (International Foundation for Telemetering, 1990-11)
      Sensor slaying consists of pointing a secondary (slave) sensor to a target vehicle, coordinates of which are defined by measurements from a primary (master) sensor or set of master sensors. For typical range applications, the secondary sensor does not possess an autonomous tracking capability; thus, pointing commands for the secondary sensors must be derived from an external source, i.e., the primary sensor or system. A common example of a range slaving system consists of an optical sensor (e.g., a cine- of video theodolite) slaved to a tracking radar. In this instance, radar measurements (range, azimuth, elevation) are typically converted into a cartesian set (x, y, z), followed by the computation of the azimuth and elevation angles from the theodolite site to the designated point. These angles define commands for theodolite pointing.
    • Modified Instrumentation for Torsional Impulse Projectiles

      PETRELLESE, JOSEPH, JR.; US ARMAMENT RESEARCH, DEVELOPMENT AND ENGINEERING CENTER (International Foundation for Telemetering, 1990-11)
      The demand for test projectiles instrumented for gathering in-bore torsional impulse data has been steadily increasing. A test projectile consists of a telemeter, 12 accelerometers, and the remaining necessary hardware. Cost, availability, and survivability of commercial accelerometers being used have become a major concern. In-house testing of a new source and different technology accelerometer show a cost benefit, higher availability and a much higher survivability rate. This paper outlines the recent progress of qualifying a new source and different technology accelerometer, which leads to a modification of the current Torsional Impulse test projectile, along with potential developments to insure a more cost effective, available, and reliable test projectile to be used in future torsional impulse tests.
    • Modulation Index and FM Improvement for Analog TV

      Baylor, J. Thomas; Loral Conic (International Foundation for Telemetering, 1990-11)
      The concepts of modulation index and FM improvement are simple and straightforward when the modulating signals are sinesoidal. For a complex baseband waveform such as analog TV, the FM improvement may be seriously underestimated. A method for computer simulation of video waveforms and the resulting spectra are presented.

      Ferguson, D.; Meyers, D.; Gemmill, P.; Pereira, C.; Honeywell Systems and Research Center; Army Armament Research, Development and Engineering Center (International Foundation for Telemetering, 1990-11)
      Instrumentation for taking dynamic in-bore measurements during high accelerations typically has been limited to accelerations under 20,000 g’s. In munition development and testing, there is a need for telemetry instrumentation that can relay dynamic performance data at 100,000 g’s. This paper describes the development and testing of a stable, regulated, telemetry transmitter that has been successfully tested to 67,400 g’s.