الفهرس 
1. IntroductionOnly 14 pages are availabe for public view
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Abstract
Optical wireless communications (OWC) has become a promising trend
nowadays with the rapidly increasing demand for wireless data, while more and
more crowded is the radio frequency (RF) spectrum. OWC is intended to
complement conventional RF communications, especially for indoor short and
medium range data transmission. Several types of single carrier modulation
waveforms such as on-off keying (OOK), M-ary pulse amplitude modulation (MPAM),
and M-ary quadrature amplitude modulation (M-QAM) have been applied
to OWC, but they suffer from the frequency-selective OWC channel as the data
rates increase. Orthogonal frequency division multiplexing (OFDM) has the ability
to boost achievable data rates. Thus, it is considered for OWC. OFDM can utilize
the available LED modulation and width with adaptive bit and energy loading of
different frequency sub-bands. Recently, the fast growing solid-state lighting (SSL)
technology has fueled the research on visible light communications (VLC), which
is a sub-category of OWC, which is utilized for illumination as well as
communication. VLC is a unipolar communication system, where only the real
(positive) signals are used for information transmission. It may suffer from many
problems associated with its traveling optical signal like multi-path fading, channel
dispersion and inter-symbol interference which cause system performance
degradation. OFDM can be used to mitigate and compensate for these problems.
However, traditional OFDM offers complex signals with real and imaginary parts,
which makes traditional OFDM not suitable for optical wireless communications.
Unipolar OFDM deals with real (positive) signals, which makes it the most
efficient technology for OWC. There are many different OWC-based unipolar
OFDM techniques that can be used with IM/DD. This thesis presents a proposed
model for indoor optical wireless communication utilizing hamming error
correction coding associated with minimum mean square error (MMSE) equalizer
with the evaluation comparison of performance and complexity for proposed
Hamming code and LDPC code with different coding rates.