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FY 1979 Technical Progress Report

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FY 1979 Technical Progress Report INSTITUTE FOR TELECOMMUNICATION SCIENCES OF THE NATIONAL TELECOMMUNICATIONS AND INFORMATION ADMINISTRATION ANNUAL TECHNICAL PROGRESS REPORT 1979 For the period from Oct. 1, 1978 through Sept. 30, 1979 U.S. DEPARTMENT OF COMMERCE National Telecommunications and Information Administration -·- ADMINISTRATOR Henry Geller DEPUTY ADMINISTRATOR Edward Zimmerman DEPUTY ADMINISTRATOR FOR OPERATIONS Stanley Cohn OFFICE OF PLANNING & POLICY COORDINATION Samuel Williams Act'g Dep. Dir. I OFFICEI OF OFFICEI OF OFFICEI OF OFFICE OF CONGRESSIONALI THE CHIEF COUNSEL INTERNATIONAL AFFAIRS ADM IN !STRATI 0 N & PUBLIC AFFAIRS Gregg Skall, Chief Counsel Veronica Ahern, Director Cloyd Dodson, Director William Garrison Director OFFICE OF OFFICE OF FEDERAL SYSTEMS INSTITUTE FOR OFFICE OF POLICY TELECOMMUNICATIONSI I I & DEVELOPMENT ANALYSIS I & SPECTRUM MANAGEMENT TELECOMMUNICATION SCIENCES APPLICATIONS Dale Hatfield William Lucas Donald Jansky Douglass Crombie, Associate Admin. Associate Administrator Forrest Chisman Associate Administrator Associate Administrator William Utlaut. Dep. Associate Admin. Dep. Assoc. Administrator ITS ANNUAL TECHNICAL PROGRESS REPORT 1979 For the period October 1, 1978 through Sept. 30, 1979 U.S. DEPARTMENT OF COMMERCE Juanita M. Kreps, Secretary Henry Geller. Assistant Secretary for Communications and Information TABLE OF CONTENTS PAGE LIST OF FIGURES v LIST OF TABLES ix INTRODUCTION 1 CHAPTER 1. EFFICIENT USE OF THE SPECTRUM 3 SECTION 1.1. SPECTRUM ENGINEERING TECHNIQUES 3 SECTION 1.2. SPECTRUM ENGINEERING FOR EFFICIENT SPECTRUM USE 21 SECTION 1.3. ADVANCED INSTRUMENTATION AND SPECTRUM MEASUREHENTS 35 SECTION 1.4. DETERMINATION OF SPECTRUM CONSUMING PROPERTIES 47 CHAPTER 2. SYSTEMS ENGINEERING AND EVALUATION 61 SECTION 2.1. COMMUNICATION SYSTEMS AND SERVICES ENGINEERING 61 SECTION 2.2; SATELLITE COMMUNICATIONS 84 SECTION 2.3. TERRESTRIAL RADIO SYSTEM PERFORMANCE 85 SECTION 2.4. SIMULATION AND STANDARDS 90 SECTION 2.5. FIBER OPTIC COMMUNICATIONS 91 CHAPTER 3. EM WAVE TRANSMISS ION 97 SECTION 3.1. WAVE TRANSMISSION CHARACTERISTICS 97 SECTION 3.2. CHARACTERISTICS OF THE TRANSMISSION MEDIA 99 3.2.1. Atmospheric Characteristics 99 3.2.2. Ionospheric Characteristics and Effects 113 SECTION 3. 3. DEVELOPMENT AND IMPLEMEN'rATION OF EM WAVE 115 TRANSMISS ION MODELS 3.3.1. Atmospheric Transmission Models 115 3.3.2. Ionospheric Transmission Models 119 SECTION 3.4. PREDICTION OF TRANSMISSION PARAMETERS. AND 127 SYSTEM PERFORMANCE 3.4.1. Long-Term Ionospheric Predictions 127 3.4.2. Medium Frequencies Transmission Studies 129 SECTION 3.5. APPLICATIONS 132 3.5.1. Antennas and Radiation 132 3.5.2. Transmission Through the Atmosphere: Applications 137 3.5.3. CCIR participation 149 ANNEX I. ITS PROJECTS FOR FY 79 153 ANNEX II. ORGANIZATIONAL DIRECTORY 155 ANNEX III. ALPHABETICAL LISTING OF ITS EMPLOYEES 157 ANNEX IV . ITS PUBLICATIONS FOR FISCAL YEAR 1979 159 ANNEX V. GENERAL AND HISTORICAL INFORMATION OF ITS 163 iii LIST OF FIGURES FIGURE TITLE PAGE 1-1 Coverage contours using FCC method. 5 1-2 Coverage contours using terrain correction . 6 1-3 Coverage contours (solid lines) and co-channel interference 7 contours (dashed lines) using FCC criteria 1-4 Coverage contours (solid lines) and co-channel interference 8 contours (dashed lines) using terrain correction . 1-5 Coverage contours (solid lines) and co-channel interference 9 contours (dashed lines) using terrain correction and a directional antenna for the Bakersfield facility. 1-6 Grade B coverage from licensed and planned (CP) TV stations . 11 1-7 United States paths . A scatter plot showing measured values 13 of g versus frequency for all over land paths with d greater 10 e than 80 km . Y (10) is obtained from the CCIR curves for a continental tegperate climate . 1-8 United States paths . Running medians of g versus frequency . 14 1 0 Each median uses .31 points from Figure 1, and the bars show an approximately 10% to 90% confidence interval . 1-9 Separation distance d versus d that is required to prevent 15 ss FM interference to an FM , land mobile system from a 10 MHz SS system at 150 MHz . 1-10 Power density , ILS . This graph predicts power density on the 17 ILS localizer front course. In other directions , the predictions should be adjusted according to the localizer 's horizontal antenna pattern. 1- 11 Signal ratio contours, ILS . 18 1-12 Orientation , ILS . Facility separation needed to obtain a D/U 19 of 23 dB for a time availability of 95 percent is provided as a function of undesired (ordinate) and desired (line code) course line angles. 1-13 Interference limited coverage estimates for instrument landing 20 systems (ILS ) . 1-14 Comparison of measured and predicted received signal level , 22 ground-to-air path . 1-15 Comparison of measured and predicted basic transmission loss , 23 point-to-point path . 1-16 Comparison of measured and predicted D/U ratios at an 24 aircraft for ground-based facilities . 1-17 Output format 25 1-18 Sample co-channel interference prediction for command/destruct 27 transmitters . 1-19 Plot or articulation score versus signal-to-interference ratio 28 with FM transmitter interfering with a digital receiver tuned 20 kHz below the digital transmitter. The points represent measured data , and the solid line represents a least squares fit to the data . 1-20 Measurements for city D. 30 v FIGURE TITLE � · 1-21 Measurements for city K . 31 1-22 Simulated ship positions and shore stations for the Atlantic area. 32 1-23 Simulated ship positions and shore stations for the Pacific area •. 32 1-24 The indicated bearing error for ADF receiver A as a function of 34 the undesired-to-desired ratio. The desired signal level is 500 vV/m at 200 kHz . The parameter oh the graph is the frequency separation of thg two signals and the difference in the direction of arrival is 90 • 1-25 Radio Spectrum Measurement System (RSMS ). 36 1-26 Block diagram of RSMS van . 37 1-27 Coverage from RSMS site ip Washington , o.c. , 162-174 MHz band . 40 _ 1-28 Block diagram , tower extension cable driver All. 43 1-29 Front panel of DM-4. 45 1-30 Block diagram of DM-4 . 46 1-31 Photograph of one of the upgraded field systems with spectrum 48 analyzer. 1-32 Expected received power, normalized to power received by a half-wave 50 length dipole antenna, for four typical types of home TV receiving antenna systems when the power flow is 1 W/m at the antenna . 1-33 Map of the Chicago-Peoria area where the home TV receiving 52 antenna system measurements will be made . 1-34 Conceptual diagram of TV performance model. 53 1-35 Selectivity of a TV receiver as measured at the second 54 detector output . 1-36 Photographs of TV performance measurements. 55 1-37 The automatic , optical tracking system . The elevation axis 56 over azimuth axis, continuous rotation pedestal with zoom lens op tical subsystem is on the top . The rack of control and display equipment is on the bottom . 1-38 Measured performance of an FM receiver with a single FM interferer 58 1-39 Measured performance of an FM receiver with three equal 59 amp litude interferers . 2-1 Federal Standard 1033 parameter development approach . 63 2-2 Selected access parameters . 64 2-3 EMS telecommun ications subsystems . 70 2-4 Emergency system processes . 70 2-5 EMSS me ssage routing . 72 2-6 Criteria development proj ect overview . 76 2-7 User requirements analysis concept . 77 2-8 Potential signaling interfaces to access area digital switch 78 for transitional network environment . vi li'IGURE 'J;'ITLE ·PAGE 2-9 Local and remoted components of a switching hub . 79 2-10 Implementation concept for digital concentration, multiplexing, 81 switching, and transmission in the access area. 2-11 Interconnection of functional units for a typical area signal center . 82 2-12 Delegation of responsibilities. 83 2-13 Digital European Backbone System, Phase I. 86 2-14 Sample enhanced fault alarm system displays. 87 2-15 Status of FED-STD-1037, Vocabulary for Telecommunications. 92 2-16 Status of glossary on optical fiber waveguide communications . 95 3-1 Effects of path/antenna geometry on received signal with phase 98 interference by one ground-reflected component . Amplitude of resultant signal: R; envelope of maxima and minima: FE ; fading range: RF·. Abscissa is ratio of depression angle of reflection point to antenna beamwidth . 3-2 Profile of Radio Building/SAO Tower for k = 4/3 showing diffraction 100 ridge . 3-3 Ray tracing for layer with ducting gradient of -471 N/km . 100 3-4 Example of measured data at 28.8 GHz compared with results 101 expected from knife-edge diffraction theory . 3-5 Molecular (ma inly o ) attenuation rates at four height levels 102 2 between 0 and 30 km for medium {R . H. = 50%) humidity . 3-6 An example of the power impulse response measured over a 100 mile 104 troposcatter path in southern Arizona . The log response function shows received power spread to delays of 0.4 �s beyond the initial response. 3-7 Photograph of measurement path from transmitter to crest 106 (about 60 meters) . 3-8 Photograph of receiving terminal. 106 3-9 Examples of clear , well-defined paths . 108 3-10 Results for an obstacle having a radius of curvature from 0 to 1.0. 109 3-11 Normalized results for path 6, 9.6 GHz . 109 3- 12 Results for path 6, 28 .8 GHz . 110 3-13 Comparison of measured alarm probability (9 .6 GHz, decision 110 threshold at optimum) with two theoretical alarm probabilities. 3-14 Diffraction results . 111 3-15 Ray trace showing first-Fresnel ellipsoid for Radio Building/ 112 Erie path. 3-16 Examples of ionograms for the Salisbury, Australia, to Alamosa, 114 Colorado, path with (right side) and without (left side) the artificial ionospheric scatterer.
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