Coexistence communication infrastructure for dense wavelength division multiplexing and passive optical networks

A method of coupling a PON with a DWDM network infrastructure, comprising:

• deploying a bandpass filter having a first coupling, a second coupling, and a third coupling, wherein:
• the first coupling of the bandpass filter is coupled to a first arrayed wave grating (AWG);
• the second coupling of the bandpass filter is coupled to an optical line terminal (OLT);
• the third coupling of the bandpass filter is coupled to an optical switch;
• and
• deploying a 2×2 optical coupler coupled with the optical switch to provide an optical working path and an optical protection path, wherein first and second couplings of the 2×2 optical coupler are coupled to couplings of the optical switch, a third coupling of the 2×2 optical coupler is coupled to a second AWG, and a fourth coupling of the 2×2 optical coupler is coupled to a stopband filter;
• receiving, at the first coupling of the bandpass filter, an upstream optical signal from one or more field components;
• filtering the upstream optical signal with the bandpass filter to provide a filtered upstream optical signal;
• and
• conveying unfiltered portions of the upstream optical signal to the OLT via the second coupling of the bandpass filter and conveying the filtered upstream optical signal to the first AWG via the third coupling of the bandpass filter.

A fiber optic network comprising:

• passive optical network (PON) components including an optical line terminal (OLT) and an optical network terminal (ONT);
• dense wavelength division multiplexing (DWDM) components including a pair of arrayed wave gratings (AWGs);
• a bandpass filter having a first coupling coupled to a first AWG of the pair and a second coupling coupled to the OLT,
• an optical switch coupled to a third coupling of the bandpass filter;
• and
• a 2×2 optical coupler coupled with the optical switch to provide an optical working path and an optical protection path, wherein first and second couplings of the 2×2 optical coupler are coupled to couplings of the optical switch, a third coupling of the 2×2 optical coupler is coupled to a second AWG of the pair, and a fourth coupling of the 2×2 optical coupler is coupled to a stopband filter, wherein the bandpass filter:
• filters an upstream optical signal received via a third coupling to provide a filtered upstream optical signal;
• and
• conveys unfiltered portions of the upstream optical signal to the OLT via the second coupling and conveys the filtered upstream optical signal to the first AWG via the first coupling.