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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

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 simulation results exhibit that our proposed dual-branch PEADO-OFDM scheme outperforms the typical ADO-OFDM scheme in spectral efficiency, bit error rate (BER) and stability over the underwater channels  ...  In this work, we establish a double-gamma UOCM with three kinds of water qualities to observe the performance of the PEADO-OFDM signal in the UOWC system.  ... 
doi:10.3390/photonics8090368 fatcat:i7ptijxybfb45aoln75hnp7tpm

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.  ...  In indoor optical wireless communication systems there are M levels that the equalizer categorizes M-QAM symbols into them by applying ACO-OFDM signalling.  ... 
doi:10.1109/iraniancee.2013.6599724 fatcat:3etsphufobhvjll6qomk64g7ne

A comparison of OFDM-based modulation schemes for OWC with clipping distortion

Svilen Dimitrov, Sinan Sinanovic, Harald Haas
2011 2011 IEEE GLOBECOM Workshops (GC Wkshps)  
double-sided signal clipping.  ...  In this paper, the electrical power requirement and spectral efficiency of multi-carrier transmission schemes for optical wireless communications (OWC) are compared in the presence of front-end-induced  ...  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/glocomw.2011.6162562 dblp:conf/globecom/DimitrovSH11 fatcat:nmewh7calbhexj3ajduwhdr5q4

Efficient OFDM transceiver design for VLC sys-tems in fading channel

Jayakumari J, Rakhi K J
2018 International Journal of Engineering & Technology  
With the widespread effective usage of LEDs the visible light communication (VLC) system has brought out an increasing interest in the field of wireless communication recently.  ...  Flip-OFDM and ACO-OFDM is analyzed in fading channels.  ...  Flip-OFDM and ACO-OFDM is analyzed. From the simulation results it is seen that the Flip-OFDM-VLC system outperforms the ACO-OFDM-VLC system in terms of BER.  ... 
doi:10.14419/ijet.v7i1.8381 fatcat:ukpccjttzfaffp4ojcxiqltjsm

The design and performance analysis of optical wireless ACO-MC-CDMA system in the presence of clipping noise

Kejun Jia, Li Hao
2017 Science China Information Sciences  
The design and performance analysis of optical wireless ACO-MC-CDMA system in the presence of clipping noise.  ...  Conditioning x LED (t) within this range can result in non-linear distortion and/or double-sided signal clipping.  ...  The proposed ACO-MC-CDMA system is analyzed in this letter. Theoretical expression of SNR for ORC is derived in the presence of signal clipping.  ... 
doi:10.1007/s11432-017-9130-7 fatcat:gab23okflnfhhcpjcwvol53sxa

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

Svilen Dimitrov, Harald Haas
2013 Journal of Lightwave Technology  
In this paper, a piecewise polynomial function is proposed as a generalized model for the nonlinear transfer characteristic of the transmitter for optical wireless communications (OWC).  ...  Index Terms-Mutual information, nonlinear distortion, orthogonal frequency-division multiplexing (OFDM), optical devices, wireless communication.  ...  The BER performance of DCO-OFDM and ACO-OFDM with double-sided signal clipping has been presented in [17] , where the linearized transfer characteristic with clipping, , is considered in .  ... 
doi:10.1109/jlt.2012.2236642 fatcat:atdsqs6nvvgvrkaqgteutupjvi

Design of a Cyclic Shifted LACO-OFDM for Optical Wireless Communication

Weiwen Hu
2020 IEEE Access  
This paper proposes a cyclic shifted layer asymmetrically clipped optical orthogonal frequency division multiplexing system (CS-LACO-OFDM) for optical wireless communications.  ...  The transmitted signal in CS-LACO-OFDM is generated by combining the signal of the first layer and signals of the remaining L-1 layers with cyclic shift equivalents, where L is the number of the CS-LACO-OFDM  ...  INTRODUCTION Compared with conventional radio frequency wireless communication system, orthogonal frequency division multiplexing (OFDM) based optical wireless communication (OWC) system is perceived as  ... 
doi:10.1109/access.2020.2989931 fatcat:wvqevoruwfcutoxo46lhiiapfm

Two approaches for the modified asymmetrically clipped optical orthogonal frequency division multiplexing system

Salma D. Mohamed, Haitham S. Khallaf, Hossam Shalaby, Ivan Andonovic, Moustafa H. Aly
2013 2013 Second International Japan-Egypt Conference on Electronics, Communications and Computers (JEC-ECC)  
Our simulation results are then compared to that of both conventional ACO-OFDM and bipolar OFDM systems.  ...  In addition these modifications would eliminate the reduction in the BER performance between ACO-OFDM and bipolar OFDM and surpass its performance.  ...  Because of its many advantages, OFDM has been successfully adopted in many wired and wireless communications systems [1] - [4] .  ... 
doi:10.1109/jec-ecc.2013.6766400 fatcat:vh3cjvccpncklog3xzm55sttlu

Flip-OFDM for Unipolar Communication Systems [article]

Nirmal Fernando, Yi Hong, Emanuele Viterbo
2011 arXiv   pre-print
One of the leading examples of unipolar OFDM is asymmetric clipped optical OFDM (ACO-OFDM) originally proposed for optical communications.  ...  Unipolar communications systems can transmit information using only real and positive signals.  ...  UNIPOLAR OFDM TECHNIQUES In this section, we compare Flip-OFDM and ACO-OFDM in the general setting of unipolar communication systems. A.  ... 
arXiv:1112.0057v2 fatcat:dw2bjj5eubd4hbgdbujxarg22e

Optimum Signal Shaping in OFDM-Based Optical Wireless Communication Systems

Svilen Dimitrov, Harald Haas
2012 2012 IEEE Vehicular Technology Conference (VTC Fall)  
In this paper, a framework for optimum signal shaping in multi-carrier modulation is presented for optical wireless communications (OWC).  ...  ACO-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/vtcfall.2012.6399084 dblp:conf/vtc/DimitrovH12 fatcat:obu4zspbsfh6zap3hmpv3ex72a

Flip-OFDM for Unipolar Communication Systems

Nirmal Fernando, Yi Hong, Emanuele Viterbo
2012 IEEE Transactions on Communications  
Unipolar communications systems can transmit information using only real and positive signals.  ...  One of the leading example of unipolar OFDM is asymmetric clipped optical OFDM (ACO-OFDM) originally proposed for optical communications.  ...  UNIPOLAR OFDM TECHNIQUES In this section, we compare Flip-OFDM and ACO-OFDM in the general setting of unipolar communication systems. A.  ... 
doi:10.1109/tcomm.2012.082712.110812 fatcat:orcpyvcchvbwzj3ixffyqwzlay

Comparison of Orthogonal Frequency-Division Multiplexing and Pulse-Amplitude Modulation in Indoor Optical Wireless Links

Daniel J. F. Barros, Sarah K. Wilson, Joseph M. Kahn
2012 IEEE Transactions on Communications  
Index Terms-Optical wireless, infrared wireless, visible light communications, communications system performance, multicarrier optical systems, orthogonal frequency-division multiplexing, power allocation  ...  The three OFDM techniques are DC-clipped OFDM and asymmetrically clipped optical OFDM (ACO-OFDM) and PAM-modulated discrete multitone (PAM-DMT).  ...  There have been several approaches for reducing the DC bias in IM OFDM systems. The first technique uses hard-clipping on the negative signal peaks in order to reduce the DC bias required.  ... 
doi:10.1109/tcomm.2011.112311.100538 fatcat:mdrlloha3rcq5izcywv54enzq4

Complex Signal Mapping for Improving Spectral Efficiency of Li-Fi Systems

Ibrahim K. Sileh, Ayad A. Abdulkafi, Mohammed K. Hussein, Saad M. Hardan
2019 Journal of Telecommunications and Information Technology  
However, common OFDM schemes employ Hermitian symmetry to obtain a real-valued signal which is necessary in intensity modulation and direct detection (IM/DD) optical systems, at the expense of doubling  ...  Light fidelity (Li-Fi) systems based on the orthogonal frequency division multiplexing (OFDM) scheme have gained more attention in the communications circles, as a means to provide high spectral efficiency  ...  wireless communication systems.  ... 
doi:10.26636/jtit.2019.131719 fatcat:7xqw6pejdnexdeumr56rfi3ury

Sample indexed spatial orthogonal frequency division multiplexing

Pankil Butala Pankil Butala, Hany Elgala Hany Elgala, Thomas D. C. Little Thomas D. C. Little
2014 Chinese Optics Letters (COL)  
Asymmetrically clipped optical OFDM (ACO-OFDM) and DC-biased optical OFDM (DCO-OFDM) are two well-known optical OFDM (O-OFDM) techniques suitable for intensity-modulation direct-detection (IM/DD) optical  ...  Orthogonal frequency division multiplexing (OFDM) is widely implemented to achieve better spectral efficiency in wireless channels.  ...  The ACO-OFDM signal can be clipped at values below zero because the resulting clipping noise is shown to be orthogonal to the signal [7] .  ... 
doi:10.3788/col201412.090602 fatcat:mkuqszz56vhc7hbqloc5jip64e
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