Implementation of Underground Water for Wireless Optical Communication System using CDMA

Optical wireless communications is a powerful and cost-effective approach for high-speed wireless links that have been tightly guarded For underwater optical wireless communication, the following three optical code division multiple access (CDMA) techniques have been used. systems are associated, investigated, and presented in this paper, such as AC-biased optical CDMA (ACO-CDMA), symmetrically-SCO-OFDM (clipped optical OFDM), and unipolar CDMA (U-CDMA). Peak power constraints, light source bandwidth tag, there are so many factors to recognize, such turbulence, fading underwater signals, and channel estimation error. Advocate for a bit loading algorithm and a simplified modulation index that determines signal magnitude is being used to minimize the achievable data propagation distance. In this optimization procedure, the signal-to-noise ratio and the clipping distortion triggered by the peak power limitation are balanced (SNR). The SNR and clipping effects of the three compared CDMA techniques are represented in this paper. When the transmitted bit index is greater than the channel bandwidth, ACO-OFDM outperforms SCO- and UCDMA, according to the determined model. U-CDMA, on the other end, has a longer propagation distance but needs less transmitted power.

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Spatial Continuous Wave Laser and Spatiotemporal VCSEL for High-Speed Long Haul Optical Wireless Communication Channels

Journal of Optical Communications ◽

10.1515/joc-2019-0061 ◽

2019 ◽

Vol 0 (0) ◽

Author(s):

I. S. Amiri ◽

Ahmed Nabih Zaki Rashed ◽

Abd Elnaser A. Mohammed ◽

Ehab Salah El-Din ◽

P. Yupapin

Keyword(s):

Wireless Communication ◽

High Speed ◽

Continuous Wave ◽

Propagation Distance ◽

Q Factor ◽

Optical Wireless Communication ◽

Continuous Wave Laser ◽

Optical Wireless ◽

Cw Laser ◽

Improvement Ratio

AbstractThis study has presented spatial continuous wave laser and spatiotemporal vertical cavity surface emitting laser (VCSEL) for high speed long haul optical wireless communication channels. Possible data rates range from 40 Gb/s to 250 Gb/s over propagation distance ranges from 500 km to 2500 km. The optical wireless communication (OWC) system performance is tested through the measurement of maximum Q-factor, minimum bit error rate (BER) and signal to noise ratio (SNR). It is observed that spatiotemporal VCSEL has presented better performance than CW laser in the OWC system, especially for long haul transmission applications. It is observed that SNR improvement ratio ranges from 8.15 % to 19 % by using spatiotemporal VCSEL than CW laser for bit rate of 40 Gb/s over propagation distance ranges from 500 km to 2500 km. Max. Q-factor improvement ratio ranges from 4.62 % to 13.71 % by using spatiotemporal VCSEL than CW laser for data rate of 40 Gb/s over propagation distance ranges from 500 km to 2500 km. So it is clear that spatiotemporal VCSEL is more suitable for long haul OWC applications than other optical sources.

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SAC-OCDMA over Indoor Optical Wireless Communication (OWC) System Based on Zero Cross Correlation (ZCC) Code

Materials Science Forum ◽

10.4028/www.scientific.net/msf.857.603 ◽

2016 ◽

Vol 857 ◽

pp. 603-607 ◽

Cited By ~ 1

Author(s):

Emad Ahmed Alyan ◽

S.A. Aljunid ◽

M.S. Anuar ◽

C.B.M. Rashidi

Keyword(s):

Wireless Communication ◽

Code Division Multiple Access ◽

Multiple Access ◽

High Speed ◽

Cross Correlation ◽

Spectral Amplitude ◽

Optical Wireless Communication ◽

Optical Wireless ◽

Code Division Multiple ◽

Indoor Optical Wireless Communication

This article investigates the spectral amplitude coding, optical code division multiple access (SAC-OCDMA) over indoor optical wireless communication (WO) system for various data rates and different receiver’s positions under the effect of ambient light noise. OW technology offers high speed communication with high level of security during data transmission. But it suffers from the multiple access interference (MAI) and phase induced intensity noise (PIIN) when the system associated with simultaneous multiple users. Therefore, the optical code division multiple access (OCDMA) technology is used based on zero cross correlation (ZCC) code in order to reduce those impairments that existed in OWC systems. The major advantage of ZCC code is its ability to eliminate the PIIN, thus minimize the MAI. The results show that at a bit error rate (BER) of 10-9, the system has the ability to perform at a transmission rate up to 1.2 Gbps. It also offers an excellent degree of mobility at all positions within the room at a data rate of 622 Mbps.

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Orthogonal Frequency Division Multiplexing Techniques Comparison for Underwater Optical Wireless Communication Systems

Sensors ◽

10.3390/s19010160 ◽

2019 ◽

Vol 19 (1) ◽

pp. 160 ◽

Cited By ~ 3

Author(s):

Jie Lian ◽

Yan Gao ◽

Peng Wu ◽

Dianbin Lian

Keyword(s):

Wireless Communication ◽

Communication Systems ◽

Orthogonal Frequency Division Multiplexing ◽

Peak Power ◽

Propagation Distance ◽

Wireless Communication Systems ◽

Optical Wireless Communication ◽

Optical Wireless ◽

Power Constraint ◽

Optical Ofdm

Optical wireless communication is an energy-efficient and cost-effective solution for high-speed and highly-secure wireless connections. In this paper, we compare, discuss, and analyze three popular optical orthogonal frequency division multiplexing (OFDM) techniques, such as DC-biased optical OFDM (DCO-OFDM), asymmetrically-clipped optical OFDM (ACO-OFDM), and unipolar OFDM (U-OFDM), for underwater optical wireless communication systems. The peak power constraint, bandwidth limit of the light source, turbulence fading underwater channel, and the channel estimation error are taken into account. To maximize the achievable data propagation distance, we propose to optimize the modulation index that controls the signal magnitude, and a bitloading algorithm is applied. This optimization process trades off the clipping distortion caused by the peak power constraint and the signal to noise ratio (SNR). The SNR and clipping effects of the three compared OFDM techniques are modeled in this paper. From the numerical results, DCO-OFDM outperforms ACO- and U-OFDM when the transmitted bit rate is high compared to the channel bandwidth. Otherwise, U-OFDM can provide a longer propagation distance or requires less transmitted power.

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Influence of Channel Estimation Error on MIMO Multiplexing Using Precoding in Downlink OFDM Radio Access

IEICE Transactions on Communications ◽

10.1587/transcom.e92.b.1553 ◽

2009 ◽

Vol E92-B (5) ◽

pp. 1553-1562

Author(s):

Takashi ISOGAI ◽

Mamoru SAWAHASHI ◽

Hidekazu TAOKA ◽

Kenichi HIGUCHI

Keyword(s):

Channel Estimation ◽

Estimation Error ◽

Channel Estimation Error ◽

Radio Access

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Analysis of Inter-Satellite Optical Wireless Communication System

International Journal of Advanced Research in Computer Science and Software Engineering ◽

10.23956/ijarcsse.v7i10.267 ◽

2017 ◽

Vol 7 (10) ◽

pp. 10

Author(s):

Rajbir Singh

Keyword(s):

Wireless Communication ◽

Optical Networks ◽

Data Transmission ◽

High Speed ◽

Open Space ◽

Communication Link ◽

Optical Wireless Communication ◽

Optical Wireless ◽

High Speed Data ◽

Speed Data Transmission

Optical networks are bandwidth efficient networks are used for long haul communication providing seamless data transfer. For high speed data transmission in open space between different satellites, Inter-satellite Optical wireless communication (IsOWC) is widely used .In this paper we have evaluated the performance of IsOWC communication link for high speed data transmission .The performance of the system is evaluated on the basis of qualitative parameters such as Q-factor and BER using optisystem simulator.

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