Patent ID: 7343104
Filing Date: 2008-03-11
Classification: H04B

Abstract:
1. An optical differential phase shift key (DPSK) receiver, comprising: an optical waveguide and a delay line associated therewith configured to receive simultaneously an optical DPSK modulated signal; a star coupler having at least two inputs, at least four outputs and a radius of curvature, said at least two inputs configured to terminate said optical waveguide and said delay line, said delay line having a path length difference that delays said optical DPSK modulated signal, relative to said optical waveguide, by at least one timeslot for said receiver; and photodetectors associated with at least two of said at least four outputs and configured to provide signals indicative of digital data contained in components of said optical DPSK modulated signal, wherein an angular separation between said at least two inputs is substantially half of a product of a square root of said radius of curvature and a wavelength of said optical DPSK modulated signal that said receiver is configured to receive.