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Comparison of ACO-OFDM and DCO-OFDM in IM/DD Systems

Sanjana C Saju, Agi Joseph George
2015 International Journal of Engineering Research and  
In this paper the two Optical Wireless orthogonal frequency division multiplexing (OFDM) techniques in intensity modulated/direct detection (IM/DD) optical systems are compared.  ...  These are asymmetrically clipped optical OFDM (ACO-OFDM) and DC biased optical OFDM (DCO-OFDM).  ...  Despite the many advantages of OFDM, and its widespread use in wireless communications, OFDM has only recently been applied to optical communications.  ... 
doi:10.17577/ijertv4is041422 fatcat:kmw5t664frexvhuuh52zglpcqi

Channel Capacity of IM/DD Optical Communication Systems and of ACO-OFDM

X. Li, R. Mardling, J. Armstrong
2007 2007 IEEE International Conference on Communications  
In this paper we investigate the channel capacity of intensity modulated direct detection (IM/DD) wireless optical communication systems for an AWGN channel with a limit on the average transmitted optical  ...  We calculate the channel capacity for systems using transmitted signals with exponential and clipped Gaussian distributions, and for an ACO-OFDM system.  ...  An ACO-OFDM system is very similar to an OFDM system designed for wired or wireless communications [1] . The data to be transmitted is mapped onto a complex vector, [ ] 0 1 N A A − = A of length N.  ... 
doi:10.1109/icc.2007.358 dblp:conf/icc/LiMA07 fatcat:pdkhtb3cxjcuzgtganfcz5cpx4

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

Jie Lian, Yan Gao, Peng Wu, Dianbin Lian
2019 Sensors  
OFDM (ACO-OFDM), and unipolar OFDM (U-OFDM), for underwater optical wireless communication systems.  ...  Optical wireless communication is an energy-efficient and cost-effective solution for high-speed and highly-secure wireless connections.  ...  A bit rate comparison of DCO-, ACO-, and U-OFDM in underwater optical wireless communication systems is shown in Figure 15 .  ... 
doi:10.3390/s19010160 fatcat:jtapcch2i5bqhgaipezv62j7fu

Flip-OFDM for optical wireless communications

Nirmal Fernando, Yi Hong, Emanuele Viterbo
2011 2011 IEEE Information Theory Workshop  
We consider two uniploar OFDM techniques for optical wireless communications: asymmetric clipped optical OFDM (ACO-OFDM) and Flip-OFDM.  ...  However, ACO-OFDM has been widely studied in the literature, while the performance of Flip-OFDM has never been investigated.  ...  In particular, for slow fading, Flip-OFDM has a saving of 50% in receiver complexity over ACO-OFDM.  ... 
doi:10.1109/itw.2011.6089566 dblp:conf/itw/FernandoHV11 fatcat:6at5uaijlvccjlwyip37fjp27a

A Novel 2D ASCO-OFDM Scheme In Wireless Communication

Sreya Manoj
The asymmetrically and symmetrically clipping optical OFDM (ASCO-OFDM) in two dimensional (2D) intensity modulation direct detection (IM/DD) is a novel technique in optical wireless communication (OWC)  ...  In 2D ASCO-OFDM the asymmetrically clipping optical OFDM (ACO-OFDM) symbols and the symmetrically clipping optical (SCO)-OFDM symbols are mapped into odd columns of transmitted matrices respectively.  ...  Then two modulation schemes, asymmetrically clipping optical (ACO)-OFDM and DC biased optical (DCO)-OFDM, have been adopted to make the real signals non-negative in one dimensional (1D) optical systems  ... 
doi:10.18535/ijetst/v3i03.10 fatcat:xy7lizrcufcevkxp6fc6mzrmcm

Performance of back-propagation and self organizing map neural equalizers for asymmetrically clipped optical OFDM

Farideh Javidi, Hossein Khoshbin
2013 2013 21st Iranian Conference on Electrical Engineering (ICEE)  
This paper evaluates the performance of backpropagation (BP) and self organizing map (SOM) equalizer for indoor asymmetrically clipped optical OFDM (ACO-OFDM) wireless systems.  ...  Simulation results indicate that BP multilayer perceptron and SOM neural equalizers enhance the bit error rate performance of ACO-OFDM systems in diffused channels for high signal to noise ratio.  ...  Indoor Optical Wireless System Model Optical wireless communication system is a wireless system in which signals are transmitted through an optical channel.  ... 
doi:10.1109/iraniancee.2013.6599724 fatcat:3etsphufobhvjll6qomk64g7ne

Clipping Noise in OFDM-Based Optical Wireless Communication Systems

Svilen Dimitrov, Sinan Sinanovic, Harald Haas
2012 IEEE Transactions on Communications  
In this paper, the impact of clipping noise on optical wireless communication (OWC) systems employing orthogonal frequency division multiplexing (OFDM) is investigated.  ...  The two existing optical OFDM (O-OFDM) transmission schemes, asymmetrically clipped optical OFDM (ACO-OFDM) and directcurrent-biased optical OFDM (DCO-OFDM), are studied.  ...  Professor Haas acknowledges the Scottish Funding Council support of his position within the Edinburgh Research Partnership in Engineering and Mathematics between the University of Edinburgh and Heriot  ... 
doi:10.1109/tcomm.2012.022712.100493 fatcat:yukgsnya4vazzhfetvknzwzlpq

Optical polar OFDM: On the effect of time-domain power allocation under power and dynamic-range constraints

Hany Elgala, Sarah Kate Wilson, Thomas D. C. Little
2015 2015 IEEE Wireless Communications and Networking Conference (WCNC)  
Polar OFDM (P-OFDM) is an OFDM format that can double the spectral efficiency of existing real-valued and unipolar optical OFDM intensity-modulation with direct detection (IM/DD) optical communication  ...  In addition to a 4 dB reduction in PAPR from ACO-OFDM, we demonstrate the improvement of throughput for P-OFDM over other optical OFDM methods when the signal power is limited.  ...  The optical polar OFDM system As shown in Fig. 1 , the P-OFDM signal is obtained based on adding Cartesian-to-Polar and Polarto-Cartesian operations to the conventional RF-OFDM communication chain.  ... 
doi:10.1109/wcnc.2015.7127440 dblp:conf/wcnc/ElgalaWL15 fatcat:pnwp2lfpjrhvdplfg7x32b2mri

Timing Synchronization Method for Asymmetrically Clipped DC Biased Optical OFDM System

Yong Wang
2016 Optics and Photonics Journal  
Existing synchronization methods for RF-based OFDM system cannot be used directly in asymmetrically clipped DC biased optical of DM (ADO-OFDM) system.  ...  In a typical intensity-modulated direct-detection optical system, the information is carried on the intensity of the optical signal, and therefore can only be positive.  ...  Acknowledgements This work was financially supported by the Natural Science Foundation of China (61275082).  ... 
doi:10.4236/opj.2016.68b003 fatcat:osdtfck4h5c33cugzs3f5y2yqa

Robust Timing Synchronization for AC-OFDM Based Optical Wireless Communications [article]

Bilal A. Ranjha, Mohammadreza A. Kashani, Mohsen Kavehrad, Peng Deng
2015 arXiv   pre-print
In this paper, we present a robust timing synchronization scheme suitable for asymmetrically clipped (AC) OFDM based optical intensity modulated direct detection (IM/DD) wireless systems.  ...  Our proposed method works perfectly for ACO-OFDM, Pulse amplitude modulated discrete multitone (PAM-DMT) and discrete Hartley transform (DHT) based optical OFDM systems.  ...  on Optical Wireless Applications (COWA-"  ... 
arXiv:1504.01320v1 fatcat:cqyqj7qvazclbfaavviwx4bmzm

Information Rate of OFDM-Based Optical Wireless Communication Systems With Nonlinear Distortion

Svilen Dimitrov, Harald Haas
2013 Journal of Lightwave Technology  
The results can be considered as a lower bound on the O-OFDM system capacity.  ...  The two general multicarrier modulation formats for OWC based on orthogonal frequency-division multiplexing (OFDM), direct-current-biased optical OFDM (DCO-OFDM) and asymmetrically clipped optical OFDM  ...  Indoor femtocells in RF wireless communications systems are an example of small cells [2] .  ... 
doi:10.1109/jlt.2012.2236642 fatcat:atdsqs6nvvgvrkaqgteutupjvi

Dual-Branch Pre-Distorted Enhanced ADO-OFDM for Full-Duplex Underwater Optical Wireless Communication System

Zixian Wei, Yibin Li, Zhaoming Wang, Junbin Fang, Hongyan Fu
2021 Photonics  
In this paper, dual-branch pre-distorted enhanced asymmetrically clipped direct current (DC) biased optical orthogonal frequency division multiplexing (PEADO-OFDM) for underwater optical wireless communication  ...  The performances of PEADO-OFDM on the underwater optical channel model (UOCM) are analyzed and further compared with the typical ADO-OFDM.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/photonics8090368 fatcat:i7ptijxybfb45aoln75hnp7tpm

Performance analysis of adaptive OFDM modulation scheme in VLC vehicular communication network in realistic noise environment

Hasan Farahneh, Fatima Hussain, Xavier Fernando
2018 EURASIP Journal on Wireless Communications and Networking  
Optical wireless communications (OWC) has emerged as a strong candidate for wireless communications, due to the capacity limitation in the radio frequency (RF) spectrum.  ...  Two schemes of O-OFDM; direct current biased optical OFDM (DCO-OFDM) and asymmetrically clipped optical OFDM (ACO-OFDM) are investigated.  ...  Authors' contributions The authors have contributed jointly to all parts on the preparation of this manuscript, and all authors read and approved the final manuscript.  ... 
doi:10.1186/s13638-018-1258-3 fatcat:kcdbnstverco5j44qdbsryozu4

Spectrally efficient optical orthogonal frequency division multiplexing

Arthur James Lowery
2020 Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences  
As the DC-part of the optical signal carries no information, it is wasteful in energy; thus asymmetrically clipped optical OFDM was developed, removing any negative-going peaks below the mean.  ...  A musical analogy is also provided, which may point to how orchestral and rock music is deciphered in the brain. This article is part of the theme issue 'Optical wireless communication'.  ...  I should like to thank my colleagues and students for their collegiality and contributions to the development of optical OFDM over the years.  ... 
doi:10.1098/rsta.2019.0180 pmid:32114915 pmcid:PMC7062002 fatcat:g5wzkrsc7bfjxkueth6z647kkq

Hadamard Coded Modulation: An Alternative to OFDM for Optical Wireless Communications [article]

Mohammad Noshad, Maite Brandt-Pearce
2014 arXiv   pre-print
In this paper we introduce Hadamard coded modulation (HCM) that uses the fast Walsh-Hadamard transform (FWHT) to modulate data as an alternative technique to OFDM in direct-detection wireless optical systems  ...  high average optical powers such as visible light communications (VLC), and 2) in optical wireless systems unconstrained by average power, for which HCM achieves lower bit error rate (BER) compared to  ...  Asymmetrically clipped optical OFDM (ACO-OFDM) and DC-biased optical OFDM (DCO-OFDM) are the most popular modified forms of OFDM adapted for IM/DD optical communication systems [12] - [14] .  ... 
arXiv:1404.1148v1 fatcat:m3kgrtlofrhlnhxryskjbqxiua
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