High Power Microwaves by James Benford, Edl Schamiloglu, John A. Swegle

Introduction     1
Origins of High Power Microwaves     2
High Power Microwave Operating Regimes     3
Future Directions in High Power Microwaves     9
Further Reading     12
References     12
Designing High Power Microwave Systems     13
The Systems Approach to High Power Microwaves     13
Looking at Systems     16
Linking Components into a System     17
Prime Power     19
Pulsed Power     22
Microwave Sources     23
Mode Converter and Antenna     24
Systems Issues     25
Scoping an Advanced System     27
NAGIRA: Prototype for the SuperSystem     28
Constructing a SuperSystem     31
Antenna and Mode Converter     31
Backward Wave Oscillator     32
Pulsed Power Subsystem     34
Conclusion     41
Problems     42
References     42
High Power Microwave Applications     43
Introduction     43
High Power Microwave Weapons     43
General Aspects of High Power Microwave Weapons     46
E-Bombs     53
First-Generation High Power Microwave Weapons     54
Active Denial     55
Neutralizing Improvised Explosive Devices     56
Jamming or Predetonating Proximity-Fused Munitions     57
Vigilant Eagle     58
Missions     59
Electromagnetic Terrorism     60
Coupling     62
Hardening     64
High Power Microwave Effects on Electronics     65
Conclusion     69
High Power Radar     69
Power Beaming     71
Space Propulsion     78
Launch to Orbit     78
Launch from Orbit into Interplanetary and Interstellar Space     85
Deployment of Large Space Structures     90
Plasma Heating     91
Sources for Electron Cyclotron Resonance Heating     96
Particle Accelerators     97
Problems     103
References     105
Microwave Fundamentals     109
Introduction     109
Basic Concepts in Electromagnetics     110
Waveguides     112
Rectangular Waveguide Modes     115
Circular Waveguide Modes     121
Power Handling in Waveguides and Cavities      124
Periodic Slow-Wave Structures     133
Axially Varying Slow-Wave Structures     134
Azimuthally Varying Slow-Wave Structures     139
Cavities     144
Intense Relativistic Electron Beams     148
Space-Charge-Limited Flow in Diodes     149
Beam Pinching in High-Current Diodes     153
Space-Charge-Limited Electron Beam Flow in a Drift Tube     153
Beam Rotational Equilibria for Finite Axial Magnetic Fields     156
Magnetically Insulated Electron Layers     157
Microwave-Generating Interactions     159
Review of Fundamental Interactions     160
O-Type Source Interactions     161
M-Type Source Interactions     167
Space-Charge Devices     168
Amplifiers and Oscillators, High- and Low-Current Operating Regimes     171
Phase and Frequency Control     173
Summary     174
Problems     175
References     177
Enabling Technologies     179
Introduction     179
Pulsed Power     180
Magnetic Stores     185
Flux Compressors     186
Electron Beams and Layers     191
Cathode Materials     191
Electron Beam Diodes     195
Microwave Pulse Compression     197
Antennas and Propagation     202
Mode Converters     203
Antenna Basics     204
Narrowband Antennas     208
Wideband Antennas     212
Diagnostics     214
Power     215
Frequency     216
Bandpass Filters     216
Dispersive Lines     216
Heterodyne Detection     218
Time-Frequency Analysis     219
Phase     220
Energy     220
High Power Microwave Facilities     222
Indoor Facilities     222
Outdoor Facilities     224
Microwave Safety     226
X-Ray Safety     229
Problems     230
Further Reading     231
References     231
Ultrawideband Systems     235
Ultrawideband Defined     235
Ultrawideband Switching Technologies     239
Spark Gap Switches     239
Solid-State Switches     242
Ultrawideband Antenna Technologies     246
Ultrawideband Systems      249
Mesoband Systems     250
Subhyperband Systems     251
Hyperband Systems     253
Conclusion     255
Problems     255
References     256
Relativistic Magnetrons and MILOS     259
Introduction     259
History     260
Design Principles     262
Cold Frequency Characteristics of Magnetrons and CFAs     267
Operating Voltage and Magnetic Field     272
Characteristics of Magnetrons     274
Summary of Magnetron Design Principles     279
Operational Features     280
Fixed-Frequency Magnetrons     281
Tunable Magnetrons     285
Repetitive High-Average-Power Magnetrons     286
Magnetron-Based Testing Systems: MTD-1 and Orion     290
Research and Development Issues     291
Pulse Shortening     293
Peak Power: Phase-Locking Multiple Sources and Transparent-Cathode Magnetrons     296
Efficiency: Limiting Axial Current Loss and Radial vs. Axial Extraction     300
Fundamental Limitations     302
Power Limits     302
Efficiency Limits     305
Frequency Limits      308
MILOs     309
Crossed-Field Amplifiers     314
Summary     314
Problems     315
References     318
BWOs, MWCGs, and O-Type Cerenkov Devices     321
Introduction     321
History     322
Design Principles     324
The Slow-Wave Structure: Dimensions and Frequencies     328
Addition of the Beam: Resonant Interactions for Different Device Types     330
Start Current and Gain     336
Peak Output Power: The Role of Computer Simulation     340
Operational Features     345
MWCGs, MWDGs, and RDGs     345
BWOs     349
TWTs     353
Research and Development Issues     357
Pulse Shortening     357
BWO Operation at Lower Magnetic Fields     359
Axially Varying Slow-Wave Structures to Enhance Efficiency     360
Other O-Type Sources; DCMs, PCMs, and Plasma-Filled BWOs     361
Fundamental Limitations     361
Summary     364
Problems     365
References     370
Klystrons and Reltrons     375
Introduction     375
History      377
Design Principles     379
Voltage, Current, and Magnetic Field     379
Drift Tube Radius     381
Klystron Cavities     381
Electron Velocity Modulation, Beam Bunching, and Cavity Spacing     384
Beam Bunching in Low-Impedance Relativistic Klystrons     388
Circuit Modeling of Klystrons     391
Reltron Design Features     394
Operational Features     395
High-Impedance, Near-Relativistic Klystrons     395
High-Impedance, Relativistic Klystrons     399
Low-Impedance Klystrons     405
Reltrons     412
Research and Development Issues     414
High Power Multibeam and Sheet-Beam Klystrons     415
Low-Impedance Annular-Beam Klystrons     417
Fundamental Limitations     422
Pencil-Beam Klystrons     422
Annular-Beam Klystrons     424
Reltrons     425
Summary     426
Problems     426
References     430
Vircators, Gyrotrons and Electron Cyclotron Masers, and Free-Electron Lasers     435
Introduction     435
Vircators     436
Vircator History      437
Vircator Design Principles     438
Basic Vircator Operational Features     444
Advanced Vircators     447
Double-Anode Vircators     448
Cavity Vircators     451
Virtodes and Feedback Vircators     453
Coaxial Vircators     454
Phase Locking of Vircators     456
Fundamental Limitations and Outlook for Vircators     458
Gyrotrons and Electron Cyclotron Masers     458
History of Gyrotrons and Electron Cyclotron Masers     459
Gyrotron Design Principles     460
Gyrotron Operational Features     469
High-Average-Power Gyrotrons     469
Relativistic Gyrotrons     470
CARMs and Gyroklystrons     473
CARMs     473
Gyroklystrons     475
Outlook for Electron Cyclotron Masers     478
Free-Electron Lasers     480
History     480
Free-Electron Laser Design Principles     481
Operational Features of Free-Electron Lasers     489
Outlook for Free-Electron Lasers     495
Summary     496
Problems     497
References     500
High Power Microwave Formulary      509
Electromagnetism     509
Waveguides and Cavities     511
Pulsed Power and Beams     514
Diodes and Beams     515
Microwave Sources     517
Propagation and Antennas     519
Applications     522
Power Beaming     522
Plasma Heating     523
Index     525