Bit Error Rate Analysis of AWG Based Add-Drop Hybrid Buffer Optical Packet Switch

Optical Packet Switching (OPS) is a promising emerging technique that is utilized for next-generation data transmission attributed to the immense bandwidth of the optical fiber. In OPS for routing and buffering of packets, the core router plays an important role. An Arrayed Waveguide Grating (AWG) based hybrid buffer add-drop optical packet switch is introduced in this paper. Both optical and electronic buffer are utilized to resolve contention among packets in the switch. Switch performance is evaluated at the physical layer in terms of bit-error rate (BER) for an uncompensated and compensated switch. Packets move within the switch without any amplification in the configuration of the uncompensated switch. In case of a compensated switch, the loss incurred inside the switch is compensated by using variable gain Semiconductor Optical Amplifier (SOA). Electronic and optical buffer comparison is carried out, and the minimum power needed for the proper functioning of the switch is evaluated for acceptable limits of BER. The acceptable BER limit is BER≤10−9 while for some applications it is BER≤10−12. The results obtained shows that in the uncompensated switch, the minimum power needed for acceptable limits of BER is 0.5 mW and 0.6 mW respectively for optical buffer and 1.9mW, 2.3mW respectively for electronic buffer. In compensated switch for acceptable limits of BER, the minimum power needed is 23μW and 27 μW respectively for optical as well as an electronic buffer. The results indicate that compared to uncompensated switch compensated switch requires less power for correct operation.