AquaOptical: A Lightweight Device for High-rate Long-range Underwater Point-to-Point Communication

AbstractThis article describes AquaOptical, an underwater optical communication system. Three optical modems have been developed: a long-range system, a short-range system, and a hybrid system. We describe their hardware and software architectures and highlight trade-offs. We present pool and ocean experiments with each system. In clear water, AquaOptical achieved a data rate of 1.2 Mbit/s at distances up to 30 m. In water with visibility estimated at 3 m, AquaOptical achieved communication at data rates of 0.6 Mbit/s at distances up to 9 m.

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A BRIEF SURVEY ON UNDERWATER WIRELESS OPTICAL COMMUNICATION SYSTEM

International Journal of Research -GRANTHAALAYAH ◽

10.29121/granthaalayah.v6.i6.2018.1370 ◽

2018 ◽

Vol 6 (6) ◽

pp. 238-245

Author(s):

Amayika Kakati ◽

Deeksha Sharma ◽

Nikhil N Aggarwal

Keyword(s):

Optical Communication ◽

Data Transmission ◽

Water Environment ◽

High Rate ◽

Electromagnetic Spectrum ◽

Optical Communication System ◽

Water Types ◽

Inherent Optical Properties ◽

Wireless Optical Communication ◽

Very High

The underwater wireless optical communication (UWOC) system gives very high rate of underwater data transmission over several meters. It utilizes the visible band in the spectral range of 390-750nm of the electromagnetic spectrum. In this paper, we study various types of link configurations depending upon the circumstances in water environment. We also study the effect of various water types on the system performance. We find that the UWOC system is affected especially by inherent optical properties such as absorption and scattering and the effect of these properties is different in various water types. We also present that misalignment in UOWC system adversely affects its functioning and reliability. Finally, we present that hybrid system design for a proper systematic UOWC system.

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Secure Optical QAM Transmission Using Chaos Message Masking

Journal of Optical Communications ◽

10.1515/joc-2018-0225 ◽

2019 ◽

Vol 0 (0) ◽

Cited By ~ 3

Author(s):

Farhan Qamar ◽

Muhammad Khawar Islam ◽

Romana Farhan ◽

Mudassar Ali ◽

Syed Zafar Ali Shah

Keyword(s):

Optical Networks ◽

Optical Communication ◽

Binary Data ◽

Data Stream ◽

Modulation Scheme ◽

Communication Link ◽

Semiconductor Laser Diode ◽

Chaotic Region ◽

Data Rates ◽

Point To Point

AbstractThis work presents the joint use of advance modulation scheme i. e. m-QAM and optical chaos to combine the best of the two advantages i. e. higher data rates and security. A semiconductor laser diode is driven into chaotic region using direct modulation scheme and 4-QAM signal is added by Chaos message masking (CMS). The chaotically masked data stream is transmitted over an optical communication link to investigate the propagation issues and synchronization of chaos at the receiver. The transmitted chaos is synchronized at the receiver to unmask the QAM stream and binary data by using subtraction rule and conventional QAM demodulator, respectively. The deterioration of constellation diagrams and bit error rate found dependent upon transmitter/receiver synchronization and link parameters. The use of 4-QAM chaotic scheme is extendable to m-QAM and is applicable to long haul, short haul point to point and for passive optical networks.

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Self-Homodyne Coherent Optical Communication System – A Review

2020 IEEE 4th Conference on Information & Communication Technology (CICT) ◽

10.1109/cict51604.2020.9312075 ◽

2020 ◽

Author(s):

Mansi Fulzele ◽

Anamika Singh ◽

Avinash Keskar

Keyword(s):

Optical Communication ◽

Communication System ◽

Optical Communication System ◽

System A ◽

Coherent Optical Communication

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A Construction Method of LDPC Codes for Space Optical Communications Based on Protograph

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.631-632.791 ◽

2014 ◽

Vol 631-632 ◽

pp. 791-794

Author(s):

Qian Hua Zhang ◽

Jian Wu Zhang

Keyword(s):

Optical Communication ◽

Communication System ◽

Communication Systems ◽

High Speed ◽

Ldpc Codes ◽

Construction Method ◽

Optical Communication System ◽

Long Distance ◽

System A ◽

Space Optical Communication

In order to meet the requirements of low bit error-rate of the channel code in the space optical communication system, a construction method of low density parity check ( LDPC) codes with excellent performance is proposed based on protograph and quasi-cyclic expansion. It can be applied in high-speed encoding and decoding with efficient quasi-cyclic expansion. According to the proposed method, a LDPC ( 8832, 1472) suitable for the space optical communication system is constructed, in which the LDPC codes of the protograph perform very well. Simulation shows that the LDPC codes have superior error-correction performance and show no sign of error floor when the BER is in the order of 10-9, which are suitable for the long-distance space optical communication systems.

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