Experimental Demonstration of Semiconductor Optical Amplifiers for 2064 km Link Loss Compensation

We present the first experimental investigation of SOAs for long-haul high-speed communications. The impact on performance when using both SOA and EDFA amplification for multi-span WDM transmission systems was compared. For threechannel transmission over distances of up to 2064 km using a recirculating optical fibre loop, we observed a >5 dB and >2.5 dB penalty in optimal SNR when using the SOAs for 15 GBd and 49.5 GBd channels, respectively. This is attributed to the SOA’s higher noise figure and nonlinearities. At 516 km this equates to a throughput reduction of 28% at optimal launch power, demonstrating the impact of device nonlinearities that needs to be overcome for the development of low power consumption optical transmission systems. This experimental first sets a baseline for long-haul high-speed optical communication using SOAs for inline amplifiers.