Figure 3
From: A 30 Gb/s PAM4 underwater wireless laser transmission system with optical beam reducer/expander
BER performance of 30 Gb/s PAM4 UWLT systems (a) with/without an optical beam reducer over 12.5-m piped underwater channel, (b) with/without an optical beam reducer/expander over 2.5-m high-turbidity harbour underwater channel, and (c) with an optical beam expander that expands the beam diameter to 8.7 mm over 2.5-m, 5-m, and 7.5-m high-turbidity harbour underwater channel.
