Performance Evaluation of Underwater Wireless Optical Communications Links in the Presence of Different Air Bubble Populations

Investigation of the Scattering Noise in Underwater Optical Wireless Communications

“…Considering the scattering noise, the received power is −19 dBm at the FEC limit of 3 × 10 −3 , which is almost the same as [18]. Note, at the FEC limit of 3 × 10 −3 and considering the scattering noise, the maximum link spans are 20 and 4.6 m for the coastal and harbor waters, respectively, which are marginally shorter than those reported in [16,17]. Higher scattering noise coefficient results in increased BER performance degradation.…”

“…This is mainly due to the coefficient, which is lower for the clear water, see Figure 4a. Note, for the clear water and at the FEC limit of 3 × 10 −3 and considering the scattering noise, the received power is −20 dBm for the 52 m link distance, which are comparable with [17,18]. For the coastal water, the scattering noise impact is more evident, as depicted in Figure 4b, where the BER is higher compared with the case with no scattering noise.…”

“…In [16], it is shown that for the clear and coastal waters, the maximum link ranges achieved were 30 and 18 m, and 41 and 26 m for the transmit power levels of 0.1 and 1 W, respectively for the FEC BER limit of 3 × 10 −3 and a data rate of 100 Mb/s. In [17], an experimental 622 Mb/s VLC system employing a water tank (50 × 34 × 34 cm 3 ) was reported with the received power levels of −32 and −21 dBm for clear and harbor waters, respectively at the FEC BER limit of 3 × 10 −3 . However, in these works, the scattering noise was not considered.…”

Investigation of the Scattering Noise in Underwater Optical Wireless Communications

“…4a. Note, for the clear water and at the FEC limit of 3 × 10 −3 187 and considering the scattering noise, the received power is -20 dBm for the 52 m link 188 distance, which are comparable with [16,17]. For the coastal water, the scattering noise 189 impact is more evident, as depicted in Fig.…”

A 400-Gb/s WDM-PAM4 OWC System Through the Free- Space Transmission With a Water-Air-Water Link

“…Using a laser beam reducer to decrease the beam size will improve the performance of the UWLT system passing through the piped water-air-piped water link because the pipe water absorbs less laser light 32 . As for the UWLT system passing through the turbid water-air-turbid water interface, the avalanche photodiode (APD) with a trans-impedance amplifier (TIA) receiver will receive a large amount of scattered light when using a laser beam expander to increase the beam size 33,34 . Employing a laser beam expander to expand the beam size, the UWLT system will have better performance through the turbid water-air-turbid water interface.…”