|   |   | Preface |   |   | 
|   |   | Acknowledgments |   |   | 
| 1 |   | Introduction |   | 1 | 
| 2 |   | Basic Principles and Background |   | 3 | 
|   |   | Wavelength Division Multiplexing: Basic Principles |   | 3 | 
|   |   | History of WDM in a Few Words |   | 4 | 
|   |   | WDM and Time Division Multiplexing |   | 4 | 
|   |   | Wavelength Domain and Separation Between Channels |   | 5 | 
|   |   | Wavelength Allocation |   | 7 | 
|   |   | Optical Wavelength/Optical Frequency Conversion |   | 7 | 
|   |   | How Many Channels? |   | 10 | 
|   |   | Some Definitions |   | 11 | 
|   |   | Solitons |   | 12 | 
| 3 |   | Dense WDM and Demultiplexers |   | 19 | 
|   |   | Passive Components: The Current Available Choice |   | 19 | 
|   |   | AWG |   | 21 | 
|   |   | FBG |   | 27 | 
|   |   | Optical Multidielectric Filters |   | 32 | 
|   |   | Diffraction Gratings |   | 38 | 
|   |   | Cascaded Mach-Zehnder Interferometers |   | 64 | 
|   |   | Other Devices: FBG/MZ Interferometer Devices |   | 67 | 
|   |   | Methods of Broadening and Flattening the Spectral Shape of the Transmission Channels of Grating WDM |   | 68 | 
|   |   | Comparison of the Different Solutions |   | 74 | 
| 4 |   | Sources and Wavelength Converters for DWDM |   | 83 | 
|   |   | Semiconductor Lasers |   | 84 | 
|   |   | Glass-Doped-Based Lasers with Narrow Line-Widths |   | 96 | 
|   |   | Spectral Slicing of Sources |   | 98 | 
|   |   | Wavelength Converters |   | 106 | 
| 5 |   | WDM and Optical Amplification |   | 125 | 
 |   | More... |   |  |