On the Performance of Semiconductor Optical Amplifier-Assisted Outdoor Optical Wireless Links

We present an analytical framework for estimating the benefits that arise from the utilization of semiconductor optical amplifiers at the receiver of fade impaired outdoor optical wireless systems. We first investigate the impact of fading on both the signal optical power and the amplified spontaneous emission, and derive analytical relations that accurately associate the system bit-error-rate with the channel state. We then utilize the analytical relations to assess the performance of the amplified system under moderate-to-strong (γ - γ) fading in terms of first and second order signal statistics. Our results show that the receiver sensitivity improvement, which is imparted by the amplification process, can drastically reduce the average bit-error-rate, link outage probability and average fade duration, provided that the link length remains within certain limits that are determined by the turbulence intensity scenario under consideration.