# Investigation of the Scattering Noise in Underwater Optical Wireless Communications

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## Abstract

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## 1. Introduction

^{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 $3\times {10}^{-3}$. However, in these works, the scattering noise was not considered. Absorption and scattering, which have been extensively studied for different water types, can be modelled using Monte Carlo (MC) numerical simulations to determine the channel impulse response (IR) [18,19,20].

## 2. System Model

## 3. UOWC Channel Model

## 4. Scattering Noise Model

## 5. Simulation Results

## 6. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 2.**The impulse responses for three types of water: clear (50 m), coastal (20 m) and harbor (4 m).

**Figure 3.**The scattering noise coefficient($\kappa $) against the link distance for clear, coastal and harbor waters.

**Figure 5.**The variance (shot noise and scattering noise) against the link distance for three types of water: (

**a**) clear, (

**b**) coastal and (

**c**) harbor.

Water Type | $\mathit{c}\left(\mathit{\lambda}\right)\left({\mathit{m}}^{-1}\right)$ | Albedo (${\mathit{\omega}}_{0}=\mathit{b}/\mathit{c}$, $\mathit{b}=$ Scattering Coefficient) |
---|---|---|

Clear | 0.151 | 0.245 |

Coastal | 0.398 | 0.55 |

Harbor | 2.17 | 0.83 |

Parameter | Value |
---|---|

Laser wavelength ($\lambda $) | 517 nm |

Laser beam divergence | 0.75 mrad |

Beam width | 0.001 mm |

Optical power | 50 mW |

Data rate | 500 Mbps |

Low pass filter bandwidth ($BW$) | 300 MHz |

Photodetector responsivity (R) | 0.34 A/W |

Gain of amplifier (G) | 600 V/A |

Rx’s field of view | 180° |

Radius size of aperture | 10 cm |

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**MDPI and ACS Style**

Majlesein, B.; Gholami, A.; Ghassemlooy, Z.
Investigation of the Scattering Noise in Underwater Optical Wireless Communications. *Sci* **2021**, *3*, 27.
https://doi.org/10.3390/sci3020027

**AMA Style**

Majlesein B, Gholami A, Ghassemlooy Z.
Investigation of the Scattering Noise in Underwater Optical Wireless Communications. *Sci*. 2021; 3(2):27.
https://doi.org/10.3390/sci3020027

**Chicago/Turabian Style**

Majlesein, Behnaz, Asghar Gholami, and Zabih Ghassemlooy.
2021. "Investigation of the Scattering Noise in Underwater Optical Wireless Communications" *Sci* 3, no. 2: 27.
https://doi.org/10.3390/sci3020027