Optical systems are provided. A representative optical system includes an optical transceiver with an optical source and an optical receiver. The system also includes an optical waveguide. At least one of the optical source and the optical receiver is optically coupled to an intermediate portion of the optical waveguide. The optical source provides optical signals for propagation by the optical waveguide, and the optical receiver receives optical signals propagated by the optical waveguide. Methods, optical transceivers and other systems also are provided.