SMART TRANSMITTERS AND RECEIVERS FOR UNDERWATER FREE SPACE OPTICAL

COMMUNICATION

V.VAMSHI KRISHNA11VE1A0488

INTRODUCTION

Underwater vehicles, sensors, and observatories require a communication interface.

Underwater Free space optical communication-Promising alternative for Short range links.

Point to point.

A new optical front-end for underwater free-space optical communication- smart transmitter & receiver.

Benefits of smart optical systems

 Non-mechanical pointing and tracking on a moving underwater vehicle.

Maintaining link with a stationary node as an under water vehicle does a drive-by

Providing sensory information to underwater vehicles.

Electronic Switched Pointing & Tracking.

Duplex multi-user system.

Optical backscatter estimation to assess water quality

Electronic Switched Pointing & Tracking.

Smart Receiver

Goal quasi- omnidirectional system to reduce pointing and tracking requirement. characteristics

Increased field of view Angle of arrival estimation

Design

consists of a 3-D spherical array of lenses all focusing to a 2-D planar array of photodiodes.

A prototype has been constructed using seven lenses and seven photodiode.

Smart Transmitter

The smart transmitter has the following characteristics:

• Increased directionality • Electronic switched beam steering

Design

Consists of a truncated hexagonal pyramid with seven LEDs

Each LED is coupled with its own lens that converges the wide FOV of the LED to a narrower

CONCLUSION

Results show that design is capable of acting as a smart system.

Backscatter estimation experiment demonstrates linear relationship between return beam intensity and channel attenuation coefficient.

It helps to estimate water quality.

Smart Receivers

increased field of view.

estimate angle of arrival.

Transmitters :

quasi omnidirectional.

allow electronic switched beamsteering.

Thank you