Wireless and Guided Wave Electromagnetics

9 Fourier Guided Wave Optics

Abbreviations

Term	Full Name
AWG	Array waveguide grating
DWDM	Dense wavelength division multiplexing
PLC	Planar lightwave circuit
GW	Guided wave
DFT or FFT	Discrete/fast Fourier transform
DWT	Discrete wavelet transform
IFFT	Inverse FFT
oFFT	Optical FFT
oDWT	Optical DWT

9.1 Introduction

Photonic signal processing has emerged as one of the most essential techniques in modern optical communication systems beyond 100 Gb/s,^1–6 especially in the intense effort to increase the transmission capacity per wavelength lightwave channel to terabits/s. In order to increase the spectral efficiency defined as the number of bits/s that are accommodated in 1 Hz, advanced modulation formats are employed, such ...