Mitigation of Scintillation effects in WDM-FSO system using Homodyne detection

Abstract

Free Space Optics is a line of sight communication which transmits a very narrow beam width. FSO offers high bandwidth and higher data rate up to 10Gbps. FSO units are transportable, compact and are easy to redeploy. With so many advantages of FSO there exists serious limitations of atmospheric effects which makes it ine cient for long reach transmission. Environment factors act as barriers in e cient utilization of FSO technology. A major issue in FSO links is the turbulence induced fading which severely deteriorates the link performance, hence need to be alleviated for the e cient use of this rapidly emerging technology. Various researches have been carried out in FSO eld to minimize the effect of turbulence induced scintillation. One such technique has been employed in this paper in which coherent based homodyne detection is utilized in conjunction with multibeam technique in WDM-FSO system with aim to reduce the scintillation effect. The performance comparison of the homodyne detection and direct detection in terms of bit error rate, Q-factor, and eye diagram has been explored for the scintillating effect.

Performance analysis of multiple-beam WDM free space laser-communication system using homodyne detection approach

“…The maximum eye height in the case of an SB is 81 μm, while in Ref. [ 23 ] eye height value was 53 μm.

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“…In Ref. [ 23 ], the Q-factor is 6.13 in the case of SB at 10 km and 8.5 in the case of MB4 at 25 km. The maximum eye height in the case of an SB is 81 μm, while in Ref.…”

“…In Ref. [ 23 ], the minimum BER value was 7.27 × 10 −10 in the case of MB4 at 25 km. The Eye diagrams for the SB, DB, MB4 and MB8 approaches are presented in Fig.…”

“…The transmission range achieved here was 15 km. Rani et al [ 23 ] used the homodyne detection method to mitigate atmospheric turbulence in the WDM FSOC framework. The maximum transmission range and minimum transmitted power achieved here were 25 km and −3 dBm, respectively, in the MB4 approach.…”

“…In Ref. [ 23 ], they analyzed the advantages of Homodyne detection over the heterodyne detection technique.…”