PROJECT TITLE :

Performance analysis of free space optical links using multi-input multi-output and aperture averaging in presence of turbulence and various weather conditions

ABSTRACT:

The authors study the impact of multi-input multi-output (MIMO) spatial diversity schemes when utilized in a free area optical (FSO) communication link within the presence of turbulence and varied atmospheric condition like very clear air, drizzle, haze, fog etc. The performance is evaluated in terms of the bit error rate (BER) and outage probability Pout. We tend to show that MIMO schemes cause a decrease within the BER and Pout that, at low signal-to-noise ratios, is more vital in presence of very clear air and clear air as compared with haze and fog atmospheric condition. The diversity gain at a BER of ten-6 is evaluated and observed to increase as the number of transmit/receive apertures increase. But, it remains almost constant over all the weather for a given MIMO scheme and turbulence strength. The performance of FSO link with MIMO schemes is compared with a FSO link using aperture averaging. Owing to constraint on the receiver aperture diameter, the aperture averaging technique fails to provide the same reasonably performance as provided by the upper order MIMO schemes.