Summary

International Technical Conference on Circuits/Systems, Computers and Communications

2016

Session Number:W2-4

Session:

Number:W2-4-4

Quantifying the Benefits of Pulse Shaping for Equalized PAM Transmissions in VLC Systems

Su Pyae Sone,  Poompat Saengudomlert ,  

pp.819-822

Publication Date:2016/7/10

Online ISSN:2188-5079

DOI:10.34385/proc.61.W2-4-4

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Summary:
In digital data transmissions, it is known that pulse shaping can help improve the transmission performance by reducing the amount of frequency selective distortion on the transmitted signal. However, to what degree pulse shaping is needed and by how much the transmission performance is improved in the context of visible light communications (VLC) has not explicity been reported. This paper provides numerical results from simulation experiments on data transmissions using pulse amplitude moduation (PAM) over two commonly used channel models for VLC, namely the exponential channel impulse response (CIR) and the ceiling-bounced CIR. For equalization, the linear minimum mean square error (MMSE) criterion is adopted for the sake of a possible practical implementation. For unequalized PAM transmissions, numerical results indicate that pulse shaping using the square-root raised cosine pulse (SRRC) and pulse shaping using the rectangular pulse yield similar bit error rate (BER) performances. However, in the presence of linear MMSE equalization with a fixed filter length, pulse shaping using the SRRC pulse can lead to significantly lower BERs when compared to the baseline case of using the rectangular pulse.