Fig. 1. LOS link of UVLC

Fig. 2. Schematic diagram of photon motion trail

Fig. 3. Flow chart of underwater channel simulation using Monte Carlo approach

Fig. 4. Polar codes-based coding structure

Fig. 5. Distribution of different Bhattacharyya parameters for channel polarization

Fig. 6. Structure of proposed polar codes-based error correcting coding scheme

Fig. 7. Distribution of chlorophyll concentration in vertical channel of seawater

Fig. 8. Comparison of optical power between vertical channel and horizontal channel at different wavelengths [B0=3 mg/m³, Cchlzmax=8 mg/m³]. (a) 500 nm; (b) 550 nm; (c) 600 nm

Fig. 9. Comparison of optical power between vertical channel and horizontal channel at different wavelengths [B0=3 mg/m³, Cchlzmax=5 mg/m³]. (a) 500 nm; (b) 550 nm; (c) 600 nm

Fig. 10. Comparison of bit error rate and code rate between vertical channel and horizontal channel at wavelengths of 500 nm and 600 nm [B0=3 mg/m³, Cchlzmax=8 mg/m³]. (a), (b) Bit error rate; (c), (d) code rate

Fig. 11. Comparison of bit error rate and code rate between vertical channel and horizontal channel at wavelengths of 500 nm and 600 nm [B0=3 mg/m³, Cchlzmax=5 mg/m³]. (a), (b) Bit error rate; (c), (d) code rate