Patent ID: 6973268

Claim:
A system for bi-directional transmission of optical signals over a single optical medium coupled between at least two nodes, said system utilizing a first optical transmission band for signals traveling in a first direction and a second optical transmission band for signals traveling in a second direction, said system comprising: at least a first combiner/separator unit at a first of said two nodes, said first combiner/separator including an input port, an output port and a bi-directional input/output port for coupling to said single optical medium, a first optical filter within said first combiner/separator unit coupled to each of said ports therein, said first optical filter being substantially transmissive to optical signals of said first band entering said input port and exiting on said bi-directional input/output port and said first optical filter being substantially reflective for signals of said second band entering said bi-directional input/output port and exiting on said output port; and at least a second combiner/separator unit at a second of said two nodes, said second combiner/separator including an input port, an output port and a bi-directional input/output port coupled to said optical medium, a second optical filter within said second combiner/separator unit coupled to each of said ports therein of said second combiner/separator unit, said second optical filter being substantially transmissive to optical signals of said second band entering said input port and exiting on said bi-directional input/output port and said second optical filter being substantially reflective for signals of said first band entering said bi-directional input output port and exiting on said single direction output port, wherein said first optical filter and said second optical filter are in an alternating arrangement.