PHY Error Models for ns-2 Simulation of FSO Packet Networks over Turbulence Channels

We propose a framework on the construction of physical (PHY) layer error models for free-space optical (FSO) networks over turbulence-induced fading channels. The constructed PHY error models can be used for simulation study and performance evaluation of various upper-layer protocols over FSO networks using the popular network simulator ns-2. In particular, two-state and multi-state Markov chain models are considered for the FSO links with single- and multi-rate transmission schemes under the impact of atmospheric turbulence conditions. We confirm the effectiveness of the proposed framework and demonstrate the simulation study of several popular protocols, including the Transmission Control Protocol (TCP) and Automatic Repeat reQuest (ARQ), over FSO networks.