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NASA Reference Publication 1076 NASA Reference Publication 1076 Satellite Power System: Concept Development and Evaluation Program Volume 111 - Power Transmission and Reception Technical Summary and Assessment R. H. Dietz, G. D. Amdt, J. W. Seyl, L. Leopold, and J. S. Kelley Lyndon E. Johnson Space Center Houston, Texas National Aeronautics and Space Administration Scientific and Technical Information Branch 1981 CONTENTS Section Page SUMMARY..... .......................... 1 I. INTRODUCTION ......................... 3 11. OVERVIEW ........................... 5 A. SYSTEM ASSESSMENT ACTIVITIES ............... 5 1. SOLAR POWER SATELLITE CONTRACTED EFFORTS ....... 6 2. IN-HOUSE NASA EFFORTS ................. 6 3. SYSTEM WORRSHOP .................... 6 a. Workshop Organization ............... 6 b. Review Panel Report: Summary ........... 7 B. SYSTEM OPTIONS ...................... 7 C. SYSTEM DEFINITION DRIVERS ................. 9 D. REFERENCE SYSTEM UPDATES AND STUDIES ........... 10 1. SYSTEM PERFORMANCE .................. 10 2. PHASE CONTROL .................... 13 3. POWER AMPLIFIERS ................... 13 4. RADIATING ELEMENTS .................. 13 5. ECTENNA ....................... 13 E. SOLID-STATE CONFIGURATIONS ................ 13 F. CRITICAL SUPPORTING INVESTIGATIONS ............ 14 G. CONCLUSIONS AND REMAINING ISSUES ............. 14 iii Section Page 111 . SYSTEM STUDIES ........................ 15 A . SYSTEM PERFORMANCE .................... 15 1. REFERENCE SYSTEM MODIFICATIONS ............ 18 a . Phase Control to the Power Module (Tube) Level ....................... 18 b . Allowable Amplitude Jitter ............ 18 c . Metal-Matrix Waveguides .............. 20 d . Startup/Shutdown Procedure ............ 20 2 . COST SENSITIVITIES FOR THE REFERENCE SYSTEM EFFICIENCY CHAIN ................... 20 a . Klystron dc-rf Conversion Efficiency (85 Percent) ................... 22 b . Transmitting Antenna Efficiency (96.5 Percent) .................. 24 c . Rectenna Energy Collection Efficiency (88Percent) ................... 26 3 . ENVIRONMENT& CONSIDERATIONS ............. 30 a . Ionosphere .................... 30 b . Atmosphere .................... 31 c . Radiofrequency Interference ............ 31 4 . ALTERNATE SYSTEMS ................... 46 a . Smaller System Sizing Trade-offs ......... 47 b . Optimized Microwave Systems .2450 and 5800 Megahertz .................. 47 c . Magnetron. Laser. and Solid-state Configurations .................. 59 iv Section Page B . PHASE CONTROL ....................... 62 1. SYSTEM REQUIREMENTS AND CONCEPTS ........... 62 a . System Requirements ................ 62 b . System Concepts .................. 63 c . Conclusions and Remaining Issues ......... 64 2 . REFERENCE PHASE CONTROL SYSTEM ............ 67 a . Reference System Description ........... 67 b . Reference System Performance Evaluation ...... 74 c . End-to-End System Performance Evaluation ..... 80 3 . ALTERNATE PHASE CONTROL CONCEPTS ........... 87 a . Interferometer-Based Phase Control System ..... 87 b . Coherent Multiple-Tone Ground-Based Phase Control System .................. 90 4 . IONOSPHERfC/ATMOSPHERIC CONSIDERATIONS ........ 94 a . Ionospheric Effects on Single-Tone Pilot Beam ... 94 b . Three-Tone Pilot-Beam System for Mitigating Ionospheric Effects ................ 97 C . POWER AMPLIFIERS ..................... 102 1. INTRODUCTION ..................... 102 a . Conclusions .................... 102 b . Power Amplifier Remaining Issues ......... 103 2 . KLYSTRONS ....................... 104 a . Reference Description ............... 104 b . High-Efficiency Klystron Design Assessment .... 107 c . Life and Reliability Assessment .......... 111 d . High-Power Klystron Trade Studies ......... 114 V Section Page 3 . MAGNETRONS ...................... 114 a . Desirable Features of the Crossed-Field Microwave Generator ................ 117 b . Integration Into the Antenna Subarray ....... 119 c . Phase and Amplitude Tracking ........... 119 d . Noise Emission Properties ............. 121 e . Cathode Life of 50 Years ............. 123 4 . SOLID-STATE POWER AMPLIFIERS ............. 125 a . Device Technology for SPS During 1978 and 1979 ....................... 126 b . Amplifier Development Program ........... 131 c . Technology Forecast ................ 132 D . RADIATING ELEMENTS .................... 133 1. CONCLUSIONS AND REMAINING ISSUES ........... 133 2 . REFERENCE DESIGN DESCRIPTION ............. 134 3 . WAVEGUIDE PARAMETERS AND PERFORMANCE ......... 136 a . Subarray Tolerances ................ 136 b . Radiating-Element Tolerances ........... 138 c . Receiving-Technique Evaluation .......... 139 4 . VARIATIONS ON WAVEGUIDE TECHNIQUES .......... 141 a . Resonant Cavity Radiator ............. 141 b . Thin-Wall Slotted-Waveguide Array Fabrication ... 143 5 . HIGH-ACCURACY MEASmMENT mCHNIQUES ......... 144 vi Section Page E . RECTENNA ......................... 146 1. REFERENCE CONFIGURATION AND PERFORMANCE ........ 150 a . Scattering and Radiofrequency Interference .... 156 b . Rectenna System Optimization ........... 159 c . Rectenna Construction ............... 159 d . Direct-Current Power Combining .......... 159 e . Measured Rectenna Array Performance ........ 161 f . Lightning Protection ............... 162 2 . ALTERNATE CONCEPTS .................. 162 a . Medium-Gain Elements ......: ........ 163 b . High-Gain Elements ................ 163 c . Hogline Elements ................. 163 d . Waveguide Techniques ............... 164 e . Offshore Rectenna ................. 164 F . SOLID-STATE CONFIGURATIONS ................ 164 1. CONCLUSIONS ...................... 165 2 . REMAINING ISSUES ................... 166 3 . NOISE GENERATION ................... 167 4 . SEPARATE ANTENNA SYSTEM ................ 170 5 . SANDWICH SYSTEM .................... 177 a . Sandwich Concept ................. 180 b . Design Considerations ............... 180 c . Reference Phase Distribution ........... 188 vii Section Page IV. CRITICAL SUPPORTING INVESTIGATIONS .............. 193 A . DESIGN AND BJlEADBOARD EVALUATION OF THE SPS REFERENCE PHASE CONTROL SYSTEM ................... 193 B . FIBER OPTICS LINK ASSESSMENT ............... 200 C . S-BAND ACTIVE RETRODIRECTIVE ARRAY PHASE ERROR EVALUATION ........................ 204 1. PROCEDURE ....................... 204 2 . EXPERIMENTAL RESULTS ................. 204 D . ANTENNA ELEMENT EVALUATION ................ 206 1. THEORY AND PROCEDURE ................. 206 2 . EXPERIMENTAL RESULTS SUMMARY ............. 211 E . SOLID-STATE ANTENNA POWER COMBINER ............ 211 1. PROGRAMSUMMARY .................... 212 2 . EXPERIMENTAL RESULTS ................. 217 F . SOLID-STATE AMPLIFIER DEVELOPMENT PROGRAM ......... 217 G . MAGNETRON TUBE ASSESSMENT ................. 218 H . MICROWAVE IONOSPHERIC INTERACTION EXPERIMENT ....... 223 V . SYSTEM CONCLUSIONS AND REMAINING ISSUES ............ 231 A . CONCLUSIONS ........................ 231 1. MICROWAVE POWER TRANSMISSION ............. 231 2 . SINGLE COMPARED TO MULTIPLE ANTENNAS ......... 231 3 . FREQUENCY ....................... 231 4 . MICROWAVE SYSTEM SIZING ................ 231 5 . TYPE OF TRANSMITTING ANTENNA ............. 231 viii Section Page 6 . TYPE OF RECEIVING ANTENNA ......... .... 232 7 . ANTENNA CONSTRUCTION AND SUBARRAY AL'INEMENT .. .. 232 8 . POWER BEAM STABILITY ........... .... 232 B . EMAINING ISSUES ............... .... 232 APPENDIX .WORKSHOP ON MICROWAVE POWER TRANSMISSION SYSTEM FOR THE SOLAR POWER SATELLITE. REVIEW PANEL FINAL REPORT ..... 235 REFERENCES ............................. 247 ix TABLES Table Page 111-1 CHARACTERISTICS AND ERROR PARAMETERS OF MODIFIED MICROWAVE TRANSMISSION SYSTEM .............. 21 111-2 COST AND MASS SUMMARY FOR REFERENCE SATELLITE SUBSYSTEMS DEPENDENT ON SOLAR ARRAY POWER .............. 23 111-3 LOSSES DUE TO POWER MODULE TOLERANCES ........... 27 111-4 ATTENUATION LOSSES FOR 5-GIGAWATT SYSTEMS ......... 32 111-5 SPS INTERFERENCE LEVEL AT TDRSS WITH 1' (700 KILOMETERS) SEPARATION ........................ 42 111-6 SPS-TO-SPS RFI FOR FOUR SCENARIOS ............. 43 111-7 SPS SUMMARY COSTS FOR 2.45-GIGAHERTZ OPERATION (a) Physical parameters .................. 51 (b) Costs ......................... 51 111-8 SPS SUMMARY COSTS FOR 5.8-GIGAHERTZ OPERATION (a) Physical parameters .................. 52 (b) Costs ......................... 52 111-9 SOLARSIM SUBROUTINE PACKAGE CAPABILITIES .......... 81 111-10 REFERENCE 70.6-KILOWATT KLYSTRON DESIGN CRITERIA ...... 106 111-11 ENERGY BALANCE IN REFERENCE FIVE-SEGMENT-COLLECTOR KLYSTRON DESIGN ..................... 109 111- 12 HARMONIC MEASUREMENTS ON REPRESENTATIVE TUBES ....... 124 111-13 CHARACTERISTICS OF FOUR SOLID-STATE DEVICES INVESTIGATED ....................... 127 111-14 SPS SUBARRAY LOSSES AND DIMENSIONAL TOLERANCES ...... 137 111-15 MEASUREMENT ERROR BUDGET .................. 147 111-16 ANTENNA RANGE MEASUREMENT ERROR SUBBUDGET ......... 148 111- 17 ERROR SUBBUDGET FOR RECEImR ELECTRONICS (a) Allowable SPS errors ................. 149 (b) State-of-the-art performance ............. 149 X Table Page 111- 18 APPROACHES FOR DECREASING RECTENNA HARMONIC RADIATION ........................ 158 111-19 COMPARISON OF WEIGHTS AND LOSSES FOR VARIOUS VOLTAGE-DISTRIBUTION SYSTEMS ............... 178 111-20 SOLID-STATE-SANDWICH CONCEPT COMPARISON OF 0- AND 10-DECIBEL ANTENNA POWER TAPER .............. 183 111-21 RECOMMENDED SOLID-STATE-SANDWICH CONCEPT CHARACTERISTICS ...................... 184 111-22 NOMINAL CHARACTERISTICS OF GaAs-SANDWICH CONCEPT ...... 185 IV- 1 ITERATIVE DE SIGN PROCEDURE FOR RADIATING-STICK PARAMETERS.
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