• The Use of Binary Cyclic Codes in the Generation of Two Other Classes of High Security Codes

      Brothman, A.; Horowitz, L. M.; Halpern, S. J.; Brothman, E. H.; Reiser, R. D.; Transitel International Corporation (International Foundation for Telemetering, 1965-05)
    • International Telemetering Conference Proceedings, Volume 01 (1965)

      International Foundation for Telemetering, 1965-05
    • A New Approach to Effective Digital Filter Design

      Duncan, P. H.; Douglas Aircraft Company (International Foundation for Telemetering, 1965-05)
      In this paper the effect of modifying digital filter weights derived on a least squares error basis through multiplication by certain weighting functions is investigated. It is shown that this approach amounts to adopting frequency resolution as a filter performance criterion, in a manner analogous to resolution in spectral estimates along the lines of Blackman and Tukey. Weight formulation using the method is very simple, and working transfer functions are easily estimated without computation. Simple, effective designs are presented for low, high and band-pass (or band-stop) filters of the "cosine" or in-phase type, for cosine "low low-pass" and "sampling" filters, and for "sine" or quadrature "sampling" filters, as well as differentiators.
    • Matched Filter Systems in Rising Noise Spectrums

      Halpern, P.; Electro-Mechanical Research (International Foundation for Telemetering, 1965-05)
      It is common knowledge that the matched filters for signals in white noise have impulse responses whose time duration is exactly as long as that of the input signal. Nothing can be gained by extending the response of the matched filters to longer than one bit unless (1) the signal source is coded, or (2) the noise spectrum is rising or at least is other than white-Gaussian-ergodic. This paper discusses means of improving bit error rates without coding the source. There are essentially two ways of extending the integration time of the matched filters, each of which offers an improvement in signal-to-noise ratio. The first way is to extend the response directly to more than one bit but constrain the filter to give zero or some small pre-assigned intersymbol crosstalk. The second way is to build matched filters for multiple bits. Both techniques can be used simultaneously; i.e., matched filters can be constructed for bit patterns, and the responses can be extended to longer than the baud to which the filters are matched. Once again this extension is done under the constrain of zero or little crosstalk. In this paper, the matched filters for several examples are expanded in a rapidly converging series, each term of which is identifiable with a known network. For the cases where the shape of the noise is not known analytically, an experimental technique is given for determining sufficient statistics of the noise so that the optimum matched filters can be designed.
    • Application of a Telemetry System using DSB-AM Sub-Carriers

      Roche, A. O.; Dynatronics, Inc. (International Foundation for Telemetering, 1965-05)
      The advantages of the DSB-AM subcarrier for wideband telemetry requirements have been discussed in previous papers. The purpose of this paper is to consider the specific performance of an FM telemetry r-f link when modulated by a frequency multiplex of DSB subcarriers. The performance is evaluated by constructing an appropriate model of the subcarrier multiplex based on a predicted noise power spectrum at the r-f demodulator output. The model is used to specify the individual subcarrier amplitude values that constitute the baseband signal, which will modulate the FM transmitter. The carrier power required to produce a useful signal-to-noise ratio at the outputs of the individual subcarrier demodulators is considered in general. The relationship between the degree of transmitter deviation, receiver bandwidth and the carrier power is derived. The carrier power required for operation over typical test range distances is determined in terms of the appropriate variables. The performance of two specific examples is calculated to illustrate the use of the several formulae that are derived. The examples also serve to relate and compare the performance of the DSB system configurations to the more traditional applications. Finally, the advantage of using increased r-f bandwidth is discussed.
    • Recent Developments Pertaining to Solid-State S-Band Transmitters

      Slone, Sam; Fjeldsteld, Norman B.; Monitor Systems (International Foundation for Telemetering, 1965-05)
      This paper discusses the performance of some recent R. F. power transistors as frequency multipliers and relates this information to their use in solid state V. H. F. and U. H. F. Telemetry Transmitters. The step-recovery diode is - similarly discussed. Both devices are shown to have great promise for ultimately lowering the complexity, size, and price of Solid State S Band and L Band Telemetry Transmitters.
    • Rocket Trajectory Analysis from Telemetered Acceleration and Attitude Data

      Cooper, Oscar L.; Research Foundation, Oklahoma State University (International Foundation for Telemetering, 1965-05)
      Double integration of the longitudinal acceleration of a sounding rocket is useful as a simple means of determining its trajectory. Reasonably accurate altitude calculations can be made by this method except when surface winds alter the launch angle of the rocket. Surface wind velocity corrections can be introduced to correct velocity and position information in the horizontal direction, but accurate wind correction data is difficult to obtain for all rockets. A special solar aspect sensor was designed to be used with a commercially available magnetic aspect sensor for rocket attitude determination. This attitude data allows the longitudinal acceleration to be broken more accurately into three vector components. A feasibility study of the aspect system was made using three Aerobee-150 rockets. A digital computer trajectory program was written to utilize aspect and acceleration data for trajectory analysis. It is evident that rocket attitude data is a useful supplement to the longitudinal acceleration data for trajectory determination. More accurate magnetic aspect data is necessary, however, to refine the longitudinal acceleration technique.
    • F. M. Capture Performance - Characterization and Measurement

      Baghdady, Elie J.; Gutwein, Joseph M.; ADCOM, Inc. (International Foundation for Telemetering, 1965-05)
      The effects of interference and capture in FM reception are reviewed for the purpose of determining the basis for characterizing and measuring the capture performance of FM receivers. Capture performance criteria and performance measurement techniques are proposed for application to FM telemetry receiver evaluation.
    • Standards Re-evaluation for Wideband Magnetic Tape Recording

      Ratner, Vic A.; Defense Electronics, Inc. (International Foundation for Telemetering, 1965-05)
    • An Advanced Integral Missile Evaluation System

      Mayo-Wells, Wilfrid J. (International Foundation for Telemetering, 1965-05)
    • High "G" UHF Telemetry for Gun-Launched Sounding Probes

      Cruickshank, William J.; Ballistic Research Laboratories (International Foundation for Telemetering, 1965-05)
      The development of a UHF telemetry system that will withstand the high shock (50,000 g) of gun launched vertical sounding probes is described. The associated development of a ground based automatic angle and range tracking and receiving system using a modified AN/GMD-1A Rawin set is also presented.
    • Frequency Spectrum of an FM/FM Signal

      Holt, J. C.; Douglas Aircraft Company (International Foundation for Telemetering, 1965-05)
      Several authors have attempted to derive a mathematical model that will describe the frequency spectrum of a FM/FM signal. However, to this author's knowledge, none of the mathematical models that have been published is valid when the carrier is modulated by more than one subcarrier. In this paper an expression for a FM/FM signal is derived that is valid when IRIG specifications are applied. Then this expression is manipulated into a form that will yield the frequency spectrum when the carrier is modulated by any number of subcarriers. Then an illustration of a two subcarrier frequency spectrum is presented.
    • Analysis of FM/FM Transmission Line Distortion

      Mohnkern, Gerald L.; N.A.S.A. (International Foundation for Telemetering, 1965-05)
      An IBM 1620 computer was programmed to evaluate the effects which the variation of propagation velocity and attenuation in coaxial cables has on a frequency modulated carrier. For a nine mile length of RG-8A/U the distortion of 70kc modulation on a 1 mc carrier was severe, while for a 10 mc carrier the distortion was negligible. A typical system using 4, 6, and 9 mc carriers on a single cable was evaluated.
    • Evaluation of an Expanded FM/FM Baseband Structure

      Campbell, E. B.; Herbert, W. R.; Electro-Mechanical Research, Inc. (International Foundation for Telemetering, 1965-05)
      An experimental evaluation program was undertaken to investigate the feasibility of expanding the IRIG (Inter-Range Instrumentation Group) FM/FM baseband. The results of the evaluation indicate that with typical field equipment, three higher-frequency proportional-bandwidth channels can be added to the baseband while maintaining adequate system performance.
    • Two-Way Telemetry for Hospital Use

      Johnston, E. B.; I.T.T. Federal Labs (International Foundation for Telemetering, 1965-05)
      A radio telemetry system for transmitting physiological data from a patient is used in a receiver complex to locate the patient. Methods of stimulating the patient for research or remedial control are discussed.
    • Five Basic Methods for the Generation of Binary Cyclic Codes

      Brothman, A.; Brothman, E. H.; Halpern, S. J.; Horowitz, L. M.; Miller, A. H. (International Foundation for Telemetering, 1965-05)
    • Telemetry for 250,000-G Gun Environment

      Finger, Daniel W.; Harry Diamond Laboratories (International Foundation for Telemetering, 1965-05)
      Techniques for packaging telemetry components and systems to withstand gun launch accelerations up to 250,000-g are discussed, and the necessary and sufficient conditions for survival are established. The principal requirements are that all voids be eliminated from the package and that encapsulating resins be adequately contained. The ultra-high-g projectiles used in hypervelocity research for which these telemeters were designed are briefly described. In addition, a brief description is given of high-g telemetry systems used in the gun-fired rockets and projectiles of project HARP.
    • Telemetering Physiologic Data from Athletes

      Rose, Kenneth D.; University of Nebraska (International Foundation for Telemetering, 1965-05)
      Employing a team composed of physicians, electrical engineers, and specialists in physical education, significant dynamic physiological data has been gathered by means of radiotelemetry from athletes undergoing strenuous effort, participating in team sports, and from spectators viewing football games. Using a transistorized A.M.-F.M. transmitter carried in a padded compartment strapped comfortably onto the low back and weighing 30 oz. complete, ECG, pulse, temperature and respiration signals have been transmitted for distances up to 500 yards. The multiple technical problems surrounding distance telemetering of physiological information during active and vigorous muscular effort are discussed. Somatic muscle interference, the most troublesome artefact in dynamic electrocardiography, has been successfully circumvented by instantaneous recording of data from the momentarily inactive subject. Application of computer techniques to the analysis of exercise electrocardiograms must await procedural improvement and standardization and collection of adequate data on which to base valid programming.
    • Design Considerations in Pre-D Receiving and Recording Equipment

      Swanson, E. E.; Defense Electronics, Inc. (International Foundation for Telemetering, 1965-05)
      Design factors to be considered in wide band Pre-D recording and playback equipment for usage in a versatile Pre-D system are presented. These design factors are introduced in a discussion of both the down-translator and up-translator. The mechanisms which produce spurious outputs from the up-translator and the effects caused by these spurious outputs are treated in detail. The extension of Pre-D techniques to FM Electronics equipment is covered.
    • Conditioning and Recovery of Aircraft Position Signals Through an Existing Data Link

      Kashar, A.; Kearfott Division, General Precision Aerospace Group (International Foundation for Telemetering, 1965-05)
      A Signal Data Converter system records aircraft present po t on and altitude data on film and also displays this data in a ground shelter, allowing for real time surveillance by a ground observer. This is accomplished by adapting a unique digital data transmission system to an existing infrared video data link.