ABSTRACT
This chapter presents the fundamental principles and applications of this new field of photonic signal processing. The graphical representation of photonic circuits is described using the signal-flow graphs (SFG) and the photonic Mason’s rules. The chapter explains the significance of coherence and incoherence of lightwaves propagation through photonic circuits and hence the representation of lightwaves and circuits either by the lightwave intensity or by the photonic electromagnetic fields. The chapter provides a fundamental understanding of incoherent and coherent optical signal processing. It describes low-loss single-mode silica-based waveguides embedded on silicon substrates have been chosen as the integrated-optic technology for the design of coherent integrated-optic signal processors. The chapter presents the fundamental theory as well as the application of the SFG method in a more comprehensive manner so that the underlying principles can be easily understood and applied.
