ABSTRACT
Contents 11.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378 11.2 Optical Generation of Millimeter-Wave Signals . . . . . . . . . . . . . . . . . . . 379
11.2.1 Mach-Zehnder Modulator-Based Techniques . . . . . . . . . . . . 381 11.2.2 Optical Locking Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 384
11.3 Optical Fiber Transmission of Millimeter-Wave Signals . . . . . . . . . . . 385 11.3.1 Millimeter-Wave Radio-over-Fiber Links . . . . . . . . . . . . . . . . . 386
11.3.1.1 Concepts, Advantages, and Applications of RoF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 386
11.3.1.2 Optical External Modulation for Millimeter-Wave RoF Links . . . . . . . . . . . . . . . . . . . . . 388
11.3.1.3 RF Properties of RoF Links . . . . . . . . . . . . . . . . . . . . . 389 11.3.1.4 The Design of RoF Links . . . . . . . . . . . . . . . . . . . . . . . 390
11.3.2 Effect of Fiber Dispersion and Nonlinearity . . . . . . . . . . . . . 391 11.3.2.1 Signal Fading Induced by CD . . . . . . . . . . . . . . . . . . 391 11.3.2.2 Effect of Fiber CD on Self-Heterodyne
Millimeter-Wave RoF Links . . . . . . . . . . . . . . . . . . . . . 393
11.3.2.3 Effect of PMD on Millimeter-Wave RoF Transmission. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394
11.3.2.4 Effect of Fiber Nonlinearity . . . . . . . . . . . . . . . . . . . . 395 11.3.3 Optical Single-Sideband Modulation . . . . . . . . . . . . . . . . . . . . . 396
11.3.3.1 OSSB Modulation Using Dual-Electrode Mach-Zehnder Modulator . . . . . . . . . . . . . . . . . . . . . . 397
11.3.3.2 OSSB Modulation Incorporating EAMs . . . . . . . . 398 11.3.4 Millimeter-Wave RoF Transmission
Incorporating DWDM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399 11.3.4.1 Simultaneous Electro-Optical Up-Conversion . 399 11.3.4.2 Wavelength Interleaving in Millimeter-Wave
DWDM RoF Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 11.3.4.3 Topology for Millimeter-Wave DWDM RoF
Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401 11.3.4.4 Multiplexing, Demultiplexing,
and Optical Add/Drop Multiplexing for DWDM RoF Links . . . . . . . . . . . . . . . . . . . . . . . . . . 402
11.3.4.5 Unequally Spaced Channel Technology Minimizing Four-Wave Mixing Crosstalk in Millimeter-Wave DWDM RoF Links . . . . . . . . . . . . 405
11.3.5 Cost-Effective Design of Full-Duplex Millimeter-Wave RoF Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 406 11.3.5.1 Millimeter-Wave RoF Downlink with Remote
Local Oscillator Delivery . . . . . . . . . . . . . . . . . . . . . . . 406 11.3.5.2 Optical Wavelength Reuse in Full-Duplex
Millimeter-Wave RoF Links . . . . . . . . . . . . . . . . . . . . . 407 11.4 Multimode Radio-over-Fiber Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 409 11.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417
11.1 Introduction Millimeter waves have found potential application in the fields of communications, radar, radiometry, spectroscopy, and radio astronomy, etc. Electronic generation of millimeter waves using oscillator and frequency multiplexers has been well investigated; however, such millimeter-wave sources are usually bulky and heavy. In addition, due to the relatively large air propagation loss, the free space transmission distance of millimeter-wave signals is generally relatively short. These facts limit the use of millimeter waves in many modern systems.
