Generalization of an Optical ASA Switch

Abstract

An arrayed waveguide grating (AWG) is a kind of passive wavelength router, and it is the most promising technology for developing large optical switches. However, AWGs have poor scalability, and using small AWGs to construct a large switch has been done in many prior works. A novel AWG-based switch called ASA (AWG, Space switching, AWG) that does not use wavelength converters has been proposed. It can expand the switch size from N to N2 by using N × N AWGs. In this paper, we generalize the ASA switch by using only N × N AWGs, N × N space switches, and N wavelengths such that the switch size is expanded to Nt for any positive integer t. Since each port of an N × N AWG can transmit up to N wavelengths simultaneously, the total capacity of the generalized ASA switch is extended to be close to Nt+1 × the bandwidth of a wavelength channel, provided that the inputs which are located in the same port position of each input AWG are destined to distinct outputs.