Spectrally efficient hybrid radio frequency and visible light communication based on hermitian symmetery free with direct current biasing
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Dosyalar
Tarih
2023
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Altınbaş Üniversitesi / Lisansüstü Eğitim Enstitüsü
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
To tackle the rapidly increasing demand for Internet services from mobile devices, network
convergence is envisaged by integrating various technology domains. A recently proposed
and promising strategy to indoor wireless communications is integrating the wireless fidelity
(WiFi) and light fidelity (LiFi) namely a hybrid WiFi and LiFi networks (HWLNs). Such
type of networks can handle the short comes of each standalone technology such as the
spectrum congestion of WiFi and the limited area coverage of LiFi. In HWLNs, the WiFi
sub-network follows the IEEE.802.11series standard applying quadrature amplitude
modulation with orthogonal frequency division multiplexing QAM-OFDM to support high
speed. While LiFi sub-network follows IEEE.802.11bb standard where OFDM-based
modulation approaches are applied. In LiFi technology, light emitted diodes (LEDs) are
applied as transmitters then only the signal intensity can be used to encode the information.
Consequently, the signal needs to be real and unipolar at the input of LEDs. There are few
spatialized approaches which account for this, including the most common PAM based
discrete multitoned modulation (PAM-DMT) and direct current biased optical OFDM
(DCO-OFDM). However, all of them achieve the real signal representation on the cost of halving the spectral efficiency as they impose the Hermitian symmetry. In this work, an
optical OFDM approach named Hermitian symmetry free with direct current biasing (HSFDC) is proposed to increase the spectral efficiency of LiFi subnetwork by 100%. The
proposed HSF-DC scheme applies clipping, splitting, and reordering on the pulse amplitude
modulation based OFDM (PAM-OFDM) instead of imposing Hermitian symmetry to
achieve the real signal representation, then a suitable DC-biasing is added to ensure the
positivity of the signal. The energy efficiency of HSF-DC is manifested in the fact that it has
the least Peak-to-Average Power Ratio (PAPR) and the best Bit Error Rate (BER) compared
with the counterparts. The proposed HSF-DC is then integrated with QAM-OFDM to build
a spectrally efficient HWLN with gain of 1.3 over QAM-OFDM/PAM-DMT and QAMOFDM/DCO. Finally, computer simulations show that the proposed hybrid QAMOFDM/HSF-DC has the best BER performance over stand-alone QAM-OFDM, hybrid
QAM-OFDM/DCO and QAM-OFDM/PAM-DMT.
Açıklama
Anahtar Kelimeler
HSF-DC, HWLNs, Spectral Efficiency, BER, Energy Efficiency, PAPR, Hermitian Symmetry
Kaynak
WoS Q Değeri
Scopus Q Değeri
Cilt
Sayı
Künye
Zaidan, Z. M. Z. (2023). Spectrally efficient hybrid radio frequency and visible light communication based on hermitian symmetery free with direct current biasing. (Yayınlanmamış doktora tezi). Altınbaş Üniversitesi, Lisansüstü Eğitim Enstitüsü, İstanbul.
