Optical Filter Cascading Effects in a Phase Modulated Coherent Optical OFDM Transmission System Based on Hartley Transform
Effects when cascading optical filters are investigated for a phase modulated coherent optical OFDM system based on Hartley transform. The evaluation is performed by means of numeric simulations in a 10 Gb/s system with a total bandwidth of 10 GHz. First a back-to-back (no fiber) case is assessed. Results show a 3 dB power penalty after a single filter of only 68% of the signal bandwidth. The same penalty is achieved when cascading 10 filters of 21.6 GHz bandwidth. Additionally, the penalties associated to the introduction of fiber spans between filters are investigated.