Performance of an underwater non-line-of-sight (NLOS) wireless optical communications system utilizing LED

In this paper, the propagation of the optical signal was explored when it passes through several types of Jerlov water based on light-emitting diode. With the bit error rate (BER) test, various modulation techniques are investigated. The line-of-sight (LoS), non-line-of-sight (NLoS), and total internal reflection (TIR) methods of the optical beam are used to analyze and investigate the attenuation that occurs in the water while passing through categorized Jerlov water. The bit error rate (BER), the Q factor, and the data rate have been used as essential metrics to assess both the system performance and the quality of the link. Finding results show that the 8-PPM modulation scheme is an appropriate choice for producing a good connection in both the LoS and NLoS scenarios; however, the 256-PPM scheme is considered the optimal modulation for executing the optical link using the TIR method.