Performance Enhancement of MIMO Configurations in FSO System Under Different Weather Conditions

Abstract

Free-space optics (FSO) is an optical wireless communication technique in which free space (air, outer space or vacuum) acts as a medium between transceivers, and for the effective transmission of the optical signal, line of sight (LOS) is necessary between the transceivers. FSO works as same as in optical fiber communication but in this optical beam propagates over free space rather than cores of fiber. FSO communication is also known as terahertz communication and optical wireless communication (OWC). Weather condition (clear air, haze and fog) is one of the main impairments affecting free-space optical communication. In this simulation model under different weather conditions such as clear air, haze and fog, the two systems MIMO-FSO (4 × 4) and MIMO-FSO (8 × 8) have been analyzed. Free-space optics emerged as one of the various merits over the radio spectrum. FSO can achieve high capacity with huge unlicensed optical spectrum and less operational costs and the MIMO technique in wireless communication systems is widely used because it provides huge data throughput and increased link range without the addition of neither bandwidth nor transmitted power. To bring out results under different weather conditions (clear air, haze and fog), simulation model has been analyzed for an array of 1 km at the frequency of 193.1 GHz. The parameters of the MIMO-FSO system, i.e., Q-factor and BER, have been analyzed for MIMO-FSO (4 × 4) and MIMO-FSO (8 × 8). In this, we analyze the difference between the two MIMO-FSO (4 × 4) and MIMO-FSO (8 × 8) system and this shows that 8 × 8 MIMO-FSO has better performance to the 4 × 4 MIMO-FSO system in different weather conditions.KeywordsFree-space opticsMIMOBit error rateWireless communicationQ-factorOptiSystem 13.0