• Application of Walsh Functions to Data Acquisition Systems

      Morton, Walter (International Foundation for Telemetering, 1966-10)
      The Walsh functions are considered with respect to the following system functions: 1. Concise signal representation. 2. Arithmetic operations. 3. Convolution and filtering. 4. Transfer function analysis. 5. Special measurements and functions: 5.1 Phase. 5.2 Digitally controlled function generator (DCFG). 5.3 Power density spectrum. 5.4 Correlation functions. The foregoing operations are required of equipment in the following areas of application: 1. Seismic data processing. 2. Hybrid data systems and simulation studies. 3. Special purpose Instrumentation.
    • Predetection Diversity Combiner

      Casson, William Holton; Defense Electronics, Inc. (International Foundation for Telemetering, 1966-10)
      Pre-detection diversity combining provides a number of advantages in telemetry data reception, particularly when used in conjunction with pre-detection recording equipment. These advantages include optimal ratio signal combining before pre-detection recording, pre-detection signal-to-noise ratio and threshold improvement, higher improvement in demodulated signal-to-noise ratio as compared with postdetection combining, and a number of operational simplifications, which are further enhanced when the combiner is used with dual channel receivers. Laboratory tests verify predicted performance. Additional quantitative field data is needed, but preliminary results indicate excellent performance, and no problems in maintaining phase lock have been experienced.
    • An Experimental Investigation of the Capture Performance of FM Receivers

      Castellano, A. J., Jr.; Data-Control Systems, Inc. (International Foundation for Telemetering, 1966-10)
      This paper reports on the investigation of the effect of telemetry receivers capture ratio on overall system accuracy. Receivers with normal and improved capture ratio were compared to evaluate the methods used to measure capture ratio, determine the effect of I-F filter characteristics on capture ratio, and establish the penalty of bandwidth and distortion results including waveforms, photographs and spectral diagrams for various values of co-channel interference.
    • Surveyor Spacecraft Telecommunications

      Rickman, Frank; Kirsten, Charles; Hughes Aircraft Company; Jet Propulsion Laboratory (International Foundation for Telemetering, 1966-10)
      Although the Surveyor program is five years old, very little concerning the on-board telecommunications has been recently printed. Because much interest has been stimulated by the recent very successful Surveyor I mission, it is believed that this descriptive article of the Surveyor telecommunications system will be of general interest. The paper is oriented toward actual subsystem implementation and performance, rather than the purely analytical presentation. The reliability and flexibility of the telecommunications is detailed with some attention being given to the operational redundancy and variety of data transmission modes available. A few of the major difficulties experienced during the design and qualifications of the telecommunications equipment are touched upon, with commentary on the solutions finally used. Pertinent mission data is discussed, with a brief presentation of some telemetered AGC: signals. Finally, a summary of the experiments run on the telecommunications subsystem, both in-flight and on the lunar surface, are presented. These experiments included a deliberate in-flight increase in the data rate above the analytically predicted level for an acceptable bit error rate, a mapping of the planar array antenna gain while on the lunar surface, voice transmission via the Surveyor transponder, and subsystem performance assessments. This paper presents the results of one phase of research carried out at the Jet Propulsion Laboratory, California Institute of Technology, under Contract No. NAS7-100, sponsored by the National Aeronautics and Space Administration.
    • A User Controlled Test Data Computing System

      Fink, A. J.; Boeing Aerospace Group (International Foundation for Telemetering, 1966-10)
      Test data systems have not yet fully capitalized on the use of digital computers for the handling of test and test related data. Advancements in computing technology will make it possible to improve total efficiency of test information systems by coupling data sources to data users through remote terminals connected directly to large timesharing computing systems. The concepts which can be applied to effecting this coupling are described.
    • Requirement for a Data Quality Assurance Program

      Nichols, M. H. (International Foundation for Telemetering, 1966-10)
      The requirement for a Data Quality Assurance Program for telemetry ground station operations is outlined. Examples are given for frequency division and time division formats to demonstrate that a practical and meaningful program is within the state-of-the-art and in fact that the basic modules have already been developed for commercial communication systems. A program is recommended for expansion of the IRIG Standards to include performance criteria and specifications of end-to-end ground station tests for determining that the criteria are satisfied for each mission.
    • Telemetry System Design for Saturn Vehicles

      Frost, W. O.; Norvell, D. E.; Marshall Space Flight Center; The Boeing Company (International Foundation for Telemetering, 1966-10)
      This paper discusses the data system requirements for large space vehicles and describes a flexible telemetry system design which is used on all stages of the Saturn IB and Saturn V vehicles. The basic vehicle telemetry design provides standard assembly building blocks forming a versatile catalogue of parts from which a stage telemetry subsystem may be assembled to meet almost any conceivable monitoring requirement. In addition to its inflight monitoring function, the telemetry subsystem also provides real time data acquisition for automatic vehicle checkout.
    • A Report on the Application of Data Abbreviation on Actual Range Telemetry Data

      Maestre, N. E.; Radio Corporation of America (International Foundation for Telemetering, 1966-10)
      The growing interest in the practical applications of data abbreviation and compaction to efficiently handle large quantities of significant information have led to numerous investigations and studies of this discipline. Although there is great potential in both the airborne and ground applications, it is primarily the latter that led RCA to initial independent data abbreviation and compaction studies. It is the purpose of this report to present results of the practical application of data abbreviation to actual telemetry data recorded on magnetic tapes. The presentation will include the affects of routine parameters, the amount of redundancy information removal, and, the reduction in processing time and recording facilities. Even though these studies involved the use of telemetry data from a mission that has already occurred, the need for the inclusion of data abbreviation devices into the existing ranges to process data in real time is becoming more apparent.
    • Magnetic Recording of Radar Data

      Young, Ronald E.; Ampex Corporation (International Foundation for Telemetering, 1966-10)
      The methods presently utilized for magnetic recording of radar data are explained with reference to basic radar types. The PPI radar has a time continuous video signal and generally requires a transient free recorder of moderate data bandwidth. In addition, means must be provided to record the azimuth information in either synchro, sine-cosine or digital form. Such means are available and recommended approaches for each type of data are given. Time discontinuous radar such as the missile tracking monopulse group may utilize recorders normally designed for video service if certain pulse spacing criteria are observed. The wider data bandwidth of this type of signal makes the use of rotary head recorders mandatory. There are many applications for radar recording. Some of those described include operator training, debriefing and scoring and operational evaluation of the radar facility. The radar recorder can be a significant aid in data analysis for signature determination of satellites and planetary mapping. The radar recorder also furnishes a close facsimile of the operating radar signal for system evaluation when there are no targets to observe or when the main radar is shut down for any reason. As an illustration of the application of magnetic recording to the radar system an airborne data acquisition recorder is described along with a companion ground reproducer. These two units are presently in use in the evaluation of an airborne radar system and offer significant advantages over previously available recording equipment. The development of time base stable magnetic tape recorders capable of handling data bandwidth in excess of 5 MHz has added another facet to the instrumentation field - that of recording radar data on a real time basis for analysis at a later time. The discussion that follows illustrates the methods used in magnetic recording of radar data and cites a typical recording system.
    • Refinements on Analysis of PCM Synchronization

      Williard, Merwin W.; Symetrics Engineering (International Foundation for Telemetering, 1966-10)
      In this paper, the author reconsiders some of his previously reported assumptions on an analysis of mean time to establish PCM synchronization, and he provides further insight into the effect of specific synchronization patterns and parameters of the synchronization process. An improvements in one assumption shows how the analysis can provide slightly more accurate results. Specific recommendations are made for standardization of PCM sync patterns.
    • The Apollo Launch Data System

      Quinn, M. J.; Nasa Manned Spacecraft Center (International Foundation for Telemetering, 1966-10)
      The development of the Apollo Launch Data Telemetry System, the real-time interface between the Merritt Island Launch Area (MILA) and the Mission Control Center-Houston (MCC-H), is reviewed from its beginning through the system planning stages, and then into the final hardware implementation.
    • White Sands Missile Range Modernization

      Boone, Billy B.; White Sands Missile Range (International Foundation for Telemetering, 1966-10)
    • Solid State Microwave Power Generation

      Brounley, Richard W.; Electronic Communications, Inc. (International Foundation for Telemetering, 1966-10)
    • Microsecond Resolution Telemetry

      Moore, Jerry D.; Sandia Corporation (International Foundation for Telemetering, 1966-10)
    • Evaluation of Redundancy Reduction Algorithms

      Simpson, R. S.; University of Alabama (International Foundation for Telemetering, 1966-10)
    • Transistor-Magnetic Logic in Aerospace Timing

      Goldman, Samuel C.; Stern, Michael M.; Goldman, David J.; Di/An Controls, Inc. (International Foundation for Telemetering, 1966-10)