RF Photonic Technology in Optical Fiber Links

Half-title......Page 3
Title......Page 5
Copyright......Page 6
Contents......Page 7
Contributors......Page 15
Introduction and preface......Page 17
1.1 Introduction......Page 21
1.2 Gain and frequency response......Page 23
1.2.1 The…of directly modulated laser links......Page 25
1.2.2 The…of external modulation links......Page 29
1.2.2.1 Impedance matching to lumped element modulators......Page 33
1.2.2.2 Impedance matching to traveling wave modulators......Page 34
1.2.3 The…of photodetectors......Page 35
1.2.4 General comments on link gain......Page 37
1.3 Noise figure......Page 38
1.3.1.1 Thermal noise......Page 39
1.3.1.2 Shot noise......Page 40
1.3.2.1 The NF of a RIN noise dominated link using a directly modulated laser......Page 41
1.3.2.2 The NF of a shot noise dominated link using an external modulator......Page 42
1.3.3 Limits on noise figure......Page 44
1.4 Distortions in RF links......Page 45
1.4.1 A graphical illustration of SFDR......Page 48
1.4.2 An alternative graphical representation of nth order distortion free DR......Page 50
1.5 Summary and conclusion......Page 52
References......Page 53
2.1 Introduction......Page 55
2.2.1 Broadcast networks......Page 56
2.2.2 Switched networks......Page 57
2.3 RF subcarrier lightwave technology......Page 58
2.3.1.1 Generic system characteristics......Page 59
2.3.1.3 Transmitter......Page 61
2.3.1.4 Fiber effects......Page 64
2.3.2 Low-cost lightwave......Page 66
2.4.1 End-to-end HFC system design......Page 68
Downstream performance......Page 69
2.4.2 Architecture evolution and its impact......Page 70
References......Page 73
3.1 Introduction......Page 77
3.2.1 Gain, loss, and recombination rates......Page 78
3.2.2 Basic laser structures......Page 80
3.2.3 Threshold current and slope efficiency......Page 82
3.3.1 Single mode rate equations......Page 83
3.3.2 Small signal analysis......Page 85
3.3.3 Equivalent circuits and parasitics......Page 86
3.4.1 Fundamental response characteristics......Page 87
3.4.2 Intensity noise......Page 88
3.4.3 Harmonic and intermodulation distortion......Page 90
3.4.4 Dynamic range......Page 92
3.5.1 Modulation characteristics......Page 94
3.5.2 Frequency noise and linewidth......Page 95
References......Page 96
4.1 Introduction......Page 101
4.2 Basic modulator designs......Page 102
4.2.1 Mach–Zehnder interferometric modulator......Page 104
4.2.2 Directional coupler......Page 110
4.2.3 Other designs based on refractive index change......Page 115
4.2.4 Electroabsorption......Page 118
4.2.5 Specific details of lithium niobate material......Page 119
4.3.1 Link transfer function (gain and distortion)......Page 123
4.3.2 Linearization......Page 131
4.3.3 Optimization of link performance (noise figure and dynamic range)......Page 141
References......Page 149
5.1 Introduction......Page 153
5.2.1 Basic traveling wave design and velocity mismatch derivation......Page 154
5.2.2 Electrode structures......Page 157
5.2.3 Early broadband traveling wave modulators......Page 158
5.2.4.1 Periodic phase reversal......Page 159
5.2.4.2 Aperiodic phase reversal......Page 161
5.3.1 Tailoring the buffer layer and electrode geometry......Page 163
5.3.2 Effect of electrode wall angle......Page 166
5.4.1 Coupling to substrate modes......Page 167
5.4.2 Losses in active and non-active regions......Page 170
5.4.3 Dependence of optical response on microwave loss, velocity mismatch, and impedance mismatch......Page 171
5.4.4 Low frequency acoustic effects......Page 173
5.5.1 Motivation and design......Page 174
5.5.2 Performance......Page 175
5.6.1 Long single-pass modulator and reflection modulator......Page 178
5.6.3 Voltage minimization design......Page 180
References......Page 182
6.1 Introduction......Page 185
6.1.1 Introduction to the MQW EA modulator......Page 187
6.1.1.1 Electroabsorption......Page 188
6.1.1.2 The EA MQW waveguide modulator......Page 189
6.1.1.3 Electrical considerations of the modulator driving circuit......Page 192
6.1.2 Exciton absorption and the quantum confined Stark effect (QCSE)......Page 193
6.1.3.1 RF efficiency of the link......Page 195
6.1.3.2 Nonlinear distortions in EA modulators......Page 196
6.1.3.3 SFDR of the link......Page 197
6.2 Analysis and design of p-i-n modulators......Page 199
6.3.1 Selection of material composition......Page 201
6.3.2 Materials characterization......Page 203
6.3.3 Q and EA characteristics......Page 205
6.4.1 Fabrication of p-i-n modulators......Page 206
6.4.2 Measured performance of MQW EA WG p-i-n modulators......Page 208
6.4.3 Linearization of MQW EA modulators......Page 209
6.5 Traveling wave EA modulators......Page 214
6.6 EA modulation in a resonator......Page 218
References......Page 220
7.1 Benefits of polymer modulators......Page 223
7.2 Benefits for RF links......Page 224
7.3 Electro-optic polymer materials......Page 226
7.3.1 Chromophores......Page 227
7.3.3 Thermoplastic, thermoset, and crosslinked polymers......Page 228
7.4.1 Device design......Page 229
7.4.2 Polymer deposition......Page 230
7.4.3 Waveguide patterning and electrode fabrication......Page 231
7.4.4 Poling......Page 232
7.4.5 Endface preparation......Page 233
7.5 Frequency response......Page 234
7.6.2 Geometrical factors......Page 240
7.6.3 Material factors......Page 243
References......Page 247
8.1.1 Definitions......Page 251
8.2 Overview of photodetector structures for analog links......Page 255
8.2.1 P-N and PIN photodiodes......Page 256
8.2.2 Schottky photodiodes and MSM photodetectors......Page 258
8.3 Noise sources in optical receivers......Page 260
8.4.1 Carrier transport and circuit element effects......Page 262
8.4.2 Geometrical effect......Page 265
8.5.1 High speed surface normal photodiodes......Page 267
8.5.2 Waveguide photodiodes......Page 268
8.5.3 Traveling wave photodiodes and velocity-matched photodiodes......Page 270
8.5.4 Uni-traveling carrier photodiodes......Page 272
References......Page 273
9.1.1 Review of oscillators......Page 275
9.1.2 Signal generation for RF photonic systems......Page 276
9.1.3 OEO – A new class of oscillators......Page 277
9.2 Basics of the opto-electronic oscillator......Page 278
9.2.1 Description of the oscillator......Page 279
9.2.2.1 Oscillation threshold......Page 280
9.2.2.2 Linearization of E/O modulator’s response function......Page 281
9.2.2.3 Oscillation frequency and amplitude......Page 283
9.2.2.4 The spectrum......Page 287
9.2.2.5 The noise-to-signal ratio......Page 291
9.2.2.6 Effects of amplifier’s nonlinearity......Page 292
9.2.3.2 The phase noise measurement setup......Page 293
9.2.3.5 Phase noise as a function of oscillation power......Page 295
9.2.4 Compact OEO with integrated DFB laser/modulator module......Page 298
9.3.1 Single mode selection......Page 300
9.3.2 Analysis......Page 301
9.3.3 Experiment......Page 305
9.4 Summary and future directions......Page 307
References......Page 310
10.1 Introduction......Page 313
10.1.1 RF system frequency allocation and requirements......Page 315
10.1.2 Benefits of frequency converting photonic links......Page 316
10.2 Optical local oscillator signal generation......Page 317
10.2.1 Heterodyned laser techniques......Page 318
10.2.2 Harmonic carrier generation using integrated optical modulators......Page 321
10.2.3 Optical local oscillator generation comparison......Page 326
10.3.1 Frequency conversion configurations......Page 329
10.3.2 Link gain and noise suppression......Page 336
10.3.3 Dynamic range......Page 343
10.3.4 Applications......Page 345
10.4 Summary......Page 346
References......Page 347
11.1 Introduction......Page 355
11.2 Velocity mismatch in traveling wave electro-optic modulators......Page 356
11.3 RF loss in the traveling wave electrodes......Page 358
11.4 “True” velocity matching......Page 359
11.5 Velocity matching “on the average” by phase shifts......Page 360
11.6 Velocity matching on the average with a corporate feed......Page 363
11.7 Effect of transmission line loss in N re-phased segments......Page 364
11.8 Antenna-coupled modulators – initial experiments......Page 366
11.9.1 A 60 GHz phase modulator......Page 372
11.9.2 A 94 GHz Mach–Zehnder modulator......Page 375
11.9.3 A 94 GHz directional coupler modulator......Page 376
11.9.4 The slot Vee Mach–Zehnder modulator......Page 382
11.10 Other antenna-coupled modulators......Page 389
11.11 Summary and suggestions for future projects in antenna-coupled modulators......Page 393
References......Page 394
12.1 Introduction......Page 397
12.2 Modern wideband arrays......Page 398
12.3 LO distribution as an example of RF photonic signal remoting......Page 401
12.4.1 Phase steering and true time delay (TTD) steering for wideband arrays......Page 405
12.4.2 True time delay demonstration systems......Page 406
12.4.3 Dual band transmit array......Page 407
12.4.4 L-band conformal radar with 96 elements......Page 408
12.4.5 SHF SATCOM array for transmit and receive......Page 411
12.4.6 Multibeam Rotman lens array controlled by an RF-heterodyne photonic BFN......Page 413
12.5 New architectures for photonic beam steering......Page 416
References......Page 418
Index......Page 421