A two wire exchange system is disclosed that enables a gaming device having one communication port to function as a gaming device having a plurality of communication ports. The device provides for a waveguide optical isolator fabricated using two arms, made of optical waveguides comprising magneto-optical material, in a Mach-Zehnder interferometer configuration. Each identified traversal has an identification of either an incoming link from which each visit originated or an outgoing link to which each visit terminated. The signal processing apparatus and method search for an optimal path of a channel signal only in the maximum error generation region, thereby reducing complexity and simplifying implementing hardware while allowing for signal processing without change in hardware where changes in a channel model or conditions of an input signal occur. A substantially collimated and coherent wavefront comprising the remaining portions may be produced in a first direction, and substantially collimated and coherent wavefront comprising the cross-polarized components may be produced in a second direction.