26 m/55 Gbps air-water optical wireless communication based on an OFDM-modulated 520-nm laser diode

Abstract

We experimentally demonstrate a high-speed air-water optical wireless communication system with both downlink and uplink transmission employing 32-quadrature amplitude modulation (QAM) orthogonal frequency division multiplexing (OFDM) and a single-mode pigtailed green-light laser diode (LD). This work is an important step towards the future study on optical wireless communications between underwater platforms and airborne terminals. Over a 5-m air channel and a 21-m water channel, we achieve a 5.3-Gbps transmission without power loading (PL) and a 5.5-Gbps transmission with PL in the downlink. The corresponding bit error rates (BERs) are 2.64×10 and 2.47×10, respectively, which are below the forward error correction (FEC) criterion. A data rate of 5.5 Gbps with PL at a BER of 2.92×10 is also achieved in the uplink.

Visible diode lasers for high bitrate underwater wireless optical communications

“…Shen et al achieved the first Gbps UWOC link over 20 m with a directly modulated 450-nm laser diode [11]. Based on this study, a 21-m, 5.5 Gbps UWOC link with OFDM modulation was further demonstrated by Chen et al in 2017 [12]. The longest distance with a Gbps data rate UWOC system was demonstrated by Liu et al, who used a directly modulated 520-nm laser diode and a transmission distance of 34.5 m was achieved [13].…”

“…The recent advances of UWOC based on the visible light were summary in Fig. 2 [4][5][6][9][10][11][12][13][14][15][16][17][18][19][20][21]. Besides these data transmission underwater, a high quality video streaming was achieved in real ocean water [22].…”

Laser-based visible light communications and underwater wireless optical communications: a device perspective

“…While radio frequency (RF) can be used for underwater wireless communication, it suffers from very high attenuation in water which limits the transmission range [24][25][26]. Because of the limitations of the aforementioned alternatives, UWOC has received a lot of attention in recent years, and Figure 2 shows the recent progress in the field [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43]. These demonstrations range from test-bed experiments, such as presented in [32], and real environment tests [42].…”

A tutorial on laser-based lighting and visible light communications: device and technology [Invited]

“…Fig. 2 shows the recent research progress in UWOC [27,28,[31][32][33][34][35][36][37][38][39][40]. In contrast to LEDs, LD and superluminescent diode (SLD) emerge as alternative light sources for achieving high Gbps data rates owing to their short relaxation time and not being subject to problems of efficiency roll off.…”