OPTİMUM SIRALAMALI V-BLAST KULLANAN DİKGEN OLMAYAN ÇOKLU ERİŞİM

Öz

Dikgen olmayan çoklu erişimin (DOÇE), yaklaşmakta olan 6G standardının temel teknolojilerinden biri olması beklenmektedir. Bu, esas olarak DOÇE’nin tüm kullanıcıların aynı frekans bandını ve aynı zaman aralığını kullanmasını sağlama potansiyelinden kaynaklanmaktadır. Bu çalışmada, DOÇE çoklu girişli çoklu çıkışlı kablosuz iletişim sisteminde uygulanmaktadır. DOÇE’ye sıfıra-zorlamalı V-BLAST algoritması uygulanarak, spektral verimlilik arttırılmış ve ardışık girişim iptali gerçekleştirilmiştir. Optimum sıralama yapmak için, alıcı antenlerin imzaları karşılaştırılmış ve ilk önce hangi sinyalin çözüleceği belirlenmiştir. Optimum sıralama uygulanan sistem ile uygulanmayan sistemler kesinti olasılığı sonuçları açısından karşılaştırılmıştır. Bu sayede işaret-gürültü oranı açısından 3 dB'lik bir kazancın elde edildiği görülmektedir.

Anahtar Kelimeler

• Kablosuz haberleşme
• dikgen olmayan çoklu erişim
• çoklu giriş çoklu çıkış
• V-BLAST
• optimum sıralama

NON-ORTHOGONAL MULTIPLE ACCESS WITH V-BLAST UNDER OPTIMUM ORDERING

Öz

Non-orthogonal multiple access (NOMA) is expected to be one of the fundamental technologies of the upcoming 6G standard. This is mainly due to NOMA's potential in enabling all the users to utilize the same frequency band and the same time slot. In this paper, NOMA is implemented in a multiple-input multiple-output wireless communication system. By implementing zero-forcing V-BLAST algorithm into NOMA, spectral efficiency is improved, and successive interference cancellation is carried out. To perform optimum ordering, receive antennas’ signatures are compared and which signal to be decoded first is determined. Outage probability results of the system with optimum ordering and the same system without ordering are compared. In this way, a 3 dB gain is shown to be attained in terms of signal-to-noise ratio.

Anahtar Kelimeler

• Wireless communications
• non-orthogonal multiple access
• multiple-input multiple-output
• V-BLAST
• optimum ordering

Kaynakça

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