ABSTRACT
This chapter discusses the potential role of fiber Bragg gratings (FBGs) in enabling fiber-optic code-division multiple access (FOCDMA). It provides a brief overview of FBG technology. The chapter describes the use of FBGs for implementing several different types of FOCDMA with an emphasis on the grating properties, requirements, and modeling. Fiber gratings can be classified in two types: those that couple counterpropagating waves and are referred to as short-period or FBGs, and those that couple copropagating waves and are referred to as long-period gratings. In the FBG-based approach, the code length depends on the spectral efficiency that can be achieved, or in other words, the number of wavelength slices that the FBGs can define within the available source bandwidth and/or FBG tuning range. For proper decoding, the peak wavelengths of the FBGs must be arranged in the reverse order to temporally despread the wavelengths.
