Design and analysis of a dense wavelength-division multiplexed integrated PON-FSO system using modified OOK/DPPM modulation schemes over atmospheric turbulences

This paper reports the designing and numerical analysis of dense wavelength-division multiplexed (DWDM) transmission in an integrated passive optical network (PON)-free-space optics (FSO) system employing modified on-off keying (OOK)/digital-pulse position modulation schemes. The transmission performance has been analyzed under inter-channel crosstalk, noise errors, and weak and strong atmospheric turbulence effects for both modulation schemes. The DWDM system uses eight channels with a wavelength spacing of 0.8 nm, and each channel transmits a data rate of 2.5 Gbps for both the considered modulation formats. The results demonstrate that the DWDM channels are degraded due to inter-channel crosstalk, whereas the FSO transmission is limited as a result of atmospheric turbulence loss. The numerical results show that the proposed modulation scheme better than OOK modulation and exhibits 0.2-3 dB lower power penalty than OOK transmission.

Automated summary

This paper reports the design and numerical analysis of dense wavelength-division multiplexed transmission in an integrated passive optical network-free-space optics system, employing a modified on-off keying/digital-pulse position modulation schemes. The results show that inter-channel crosstalk degrades the DWDM channels, while atmospheric turbulence loss limits the FSO transmission. The proposed modulation scheme performs better than OOK modulation and exhibits lower power penalty than OOK transmission.