Comparison of Fourier and Trigonometric Transform based Multicarrier Modulations for Visible Light Communication

Selva Muratoğlu Çürük

Makale detayları

Comparison of Fourier and Trigonometric Transform based Multicarrier Modulations for Visible Light Communication

Yazarlar:

Selva Muratoğlu Çürük

Yayıncı:

Fırat University

Ana Başlıklar:

Wireless Communication Systems and Technologies (Incl. Microwave and Millimetrewave)

Dergi:

Turkish Journal of Science and Technology Vol.19 Issue 2, pp.397-405

Belge Tipi:

Makale

Yayın Tarihi:

9/2024

Belge Dili:

İngilizce

Document ID (Org No.):

2001328542

pISSN:

1308-9080

Anahtar kelimeler:

Özet:

 It is predicted that the radio frequency spectrum will be insufficient in the near future due to the increase in wireless data. Visible Light Communication VLC is an alternative solution, which promises high speeds. Similar to other wireless communication systems, VLC systems prefer Multicarrier Modulation MCM, but the signals are converted to be real and unipolar before transmission for optical communication. In this paper, two optical MCM groups that utilize Discrete Fourier Transform DFT and Discrete Trigonometric Transform DTT are questioned with respect to Bit Error Rate BER, spectral efficiency and complexity. DFT based techniques use complex mapped signals together with their Hermitian symmetries to obtain real output signals, while DTT based techniques already output real signals when the input signal is real mapped. It is seen that DFT based techniques have lower BERs because of used mapping. DTT based techniques improve spectral efficiency, but they are limited to real mappings with higher error rates. For both transformations, the real signals are made unipolar by adding a bias DCO-MCM, by asymmetrically clipping ACO-MCM or by sending positive and negative values separately UnO-MCM. It is shown that, adding a dc bias DCO-MCM increases BERs, where ACO-MCM and UnO-MCM have close performances with lower BERs.

 It is predicted that the radio frequency spectrum will be insufficient in the near future due to the increase in wireless data. Visible Light Communication VLC is an alternative solution, which promises high speeds. Similar to other wireless communication systems, VLC systems prefer Multicarrier Modulation MCM, but the signals are converted to be real and unipolar before transmission for optical communication. In this paper, two optical MCM groups that utilize Discrete Fourier Transform DFT and Discrete Trigonometric Transform DTT are questioned with respect to Bit Error Rate BER, spectral efficiency and complexity. DFT based techniques use complex mapped signals together with their Hermitian symmetries to obtain real output signals, while DTT based techniques already output real signals when the input signal is real mapped. It is seen that DFT based techniques have lower BERs because of used mapping. DTT based techniques improve spectral efficiency, but they are limited to real mappings with higher error rates. For both transformations, the real signals are made unipolar by adding a bias DCO-MCM, by asymmetrically clipping ACO-MCM or by sending positive and negative values separately UnO-MCM. It is shown that, adding a dc bias DCO-MCM increases BERs, where ACO-MCM and UnO-MCM have close performances with lower BERs.

 It is predicted that the radio frequency spectrum will be insufficient in the near future due to the increase in wireless data. Visible Light Communication VLC is an alternative solution, which promises high speeds. Similar to other wireless communication systems, VLC systems prefer Multicarrier Modulation MCM, but the signals are converted to be real and unipolar before transmission for optical communication. In this paper, two optical MCM groups that utilize Discrete Fourier Transform DFT and Discrete Trigonometric Transform DTT are questioned with respect to Bit Error Rate BER, spectral efficiency and complexity. DFT based techniques use complex mapped signals together with their Hermitian symmetries to obtain real output signals, while DTT based techniques already output real signals when the input signal is real mapped. It is seen that DFT based techniques have lower BERs because of used mapping. DTT based techniques improve spectral efficiency, but they are limited to real mappings with higher error rates. For both transformations, the real signals are made unipolar by adding a bias DCO-MCM, by asymmetrically clipping ACO-MCM or by sending positive and negative values separately UnO-MCM. It is shown that, adding a dc bias DCO-MCM increases BERs, where ACO-MCM and UnO-MCM have close performances with lower BERs.

 Kablosuz verideki artış nedeniyle yakın gelecekte radyo frekans spektrumunun yetersiz kalması ön görülmektedir. Görünür Işık Haberleşmesi VLC yüksek hız vaat eden alternatif bir çözümdür. VLC sistemleri, diğer kablosuz haberleşme sistemlerine benzer şekilde, Çoklu Taşıyıcılı Modülasyon MCM tercih ederler, ancak optik iletişim için iletimden önce sinyaller gerçek ve tek kutuplu olacak şekilde dönüştürülürler. Bu makalede, Ayrık Fourier Dönüşümü DFT ve Ayrık Trigonometrik Dönüşümü DTT kullanan iki optik MCM grubu Bit Hata Oranı BER, spektral verimlilik ve karmaşıklık açısından sorgulanmaktadır. DFT tabanlı teknikler, gerçek çıkış sinyali elde etmek için karmaşık eşlemeli sinyaller ve onların Hermit simetrilerini kullanırlar, DTT tabanlı tekniklerde ise giriş sinyali gerçek eşlenmiş ise çıkış zaten gerçek olacaktır. DFT tabanlı tekniklerin kullanılan eşleme nedeniyle daha düşük BERlere sahip oldukları görülmektedir. DTT tabanlı teknikler spektral verimliliği arttırır ancak bu teknikler daha yüksek hata oranlarına sahip gerçek eşlemelerle sınırlıdırlar. Her iki dönüşüm için de gerçek sinyaller, bir öngerilim eklenerek DCO-MCM, asimetrik olarak kırpılarak ACO-MCM veya pozitif ve negatif değerleri ayrı ayrı göndererek UnO-MCM tek kutuplu hale getirilir. Dc bileşen eklemek DCO-MCM BERleri arttırırken, ACO-MCM ve UnO-MCM in daha düşük BERlerle yakın performanslara sahip oldukları gösterilmiştir.

Makale detayları

Comparison of Fourier and Trigonometric Transform based Multicarrier Modulations for Visible Light Communication

Yazarlar:

Selva Muratoğlu Çürük

Yayıncı:

Fırat University

Ana Başlıklar:

Wireless Communication Systems and Technologies (Incl. Microwave and Millimetrewave)

Dergi:

Turkish Journal of Science and Technology Vol.19 Issue 2, pp.397-405

Belge Tipi:

Makale

Yayın Tarihi:

9/2024

Belge Dili:

İngilizce

Document ID (Org No.):

2001328542

pISSN:

1308-9080

Bit Error Rate

Discrete Fourier Transform

Discrete Trigonometric Transform

Multicarrier Modulation

Visible Light Communication.Bit hata oranı

ayrık fourier dönüşüm

ayrık trigonometrik dönüşüm

çok taşıyıcılı modülasyon

görünür ışık haberleşmesi.

Sayı

Makale detayları

Yazarlar: Selva Muratoğlu Çürük

Yayıncı: Fırat University

Ana Başlıklar: Wireless Communication Systems and Technologies (Incl. Microwave and Millimetrewave)

Dergi: Turkish Journal of Science and Technology Vol.19 Issue 2, pp.397-405

Belge Tipi: Makale

Yayın Tarihi: 9/2024

Belge Dili: İngilizce

Document ID (Org No.): 2001328542

pISSN: 1308-9080

Sayı

Yazarlar:

Selva Muratoğlu Çürük

Yayıncı:

Fırat University

Ana Başlıklar:

Wireless Communication Systems and Technologies (Incl. Microwave and Millimetrewave)

Dergi:

Turkish Journal of Science and Technology Vol.19 Issue 2, pp.397-405

Belge Tipi:

Makale

Yayın Tarihi:

9/2024

Belge Dili:

İngilizce

Document ID (Org No.):

2001328542

pISSN:

1308-9080