Figure 3
From: A PDM-based 128-Gb/s PAM4 fibre-FSO convergent system with OBPFs for polarisation de-multiplexing
(a) The BER performances of the PDM-based 128-Gb/s PAM4 fibre-FSO convergent system in the states of BTB, through 25 km SMF transport, through 25 km SMF transport and 500 m free-space transmission (x- and y-polarisations), as well as through 25 km SMF transport SMF and 500 m free-space transmission (single polarisation). The eye diagrams of 64-Gb/s PAM4 signal in the scenarios of (b) BTB, (c) through 25 km SMF transport and 500 m free-space transmission (x-polarisation), and (d) through 25 km SMF transport and 500 m free-space transmission (single polarisation).
