Loss analysis depending on waveguide structures for TFF-embedded PLC platform

We compare various waveguide structures such as a singlemode intersection, two sets of tapered waveguide intersections, and a singlemode-to-multimode intersection for the amount of the loss and the tolerance to the positional deviation of the thin-film-filter (TFF) in a TFF-embedded planar-lightwave-circuit platform for a bidirectional transceiver module. The configuration with a singlemode-to-multimode intersection is most efficient in a low loss and in an excellent tolerance