An apparatus for measuring optical power includes a first component configured to at least one of multiplex or demultiplex between a first composite optical waveguide and at least a first intermediate optical waveguide and a second intermediate optical waveguide. The apparatus further includes a second component configured to at least one of multiplex or demultiplex between a second composite optical waveguide and at least the first intermediate optical waveguide and the second intermediate optical waveguide. The first and second components have complimentary isolation levels. The apparatus further includes a first optical coupler positioned along the first intermediate optical waveguide and a second optical coupler positioned along the second intermediate optical waveguide. The apparatus further includes a first photodetector, a second photodetector, a first measurement device, and a second measurement device.