MC-CDMA Sistemlerinde Alt Taşıyıcı Tahsis Algoritmalarının Performanslarının İncelenmesi

Çok Taşıyıcılı Kod Bölmeli Çoklu Erişim (MC-CDMA), kablolu ve kablosuz haberleşme uygulamalarında kullanılan, yüksek hızlarda ve servis kaliteli veri iletişimi sağlayan bir çoklu erişim tekniğidir. MC-CDMA çok kullanıcılı bir teknoloji olduğu için sistemdeki kullanıcı sayısının artması; kullanıcı başına düşen taşıyıcı sayısını azaltmakta, bunun sonucunda alıcı taraftan alınan verinin bit hata oranının (BHO) artmasına ve kullanıcı başına düşen veri hızlarının azalmasına neden olmaktadır. Bu sorunu engellemek için alt taşıyıcı tahsis algoritmaları kullanılmaktadır. Bu çalışmada, MC-CDMA sisteminde toplam hızı artırmak ve verimliliği sağlamak için alt taşıyıcı tahsis algoritmalarının performansı farklı kullanıcı sayıları için incelenmiştir.

Investigation of the Subcarrier Allocation Algorithms Performance in MC-CDMA Systems

Multi Carrier Code Division Multiple Access is a multiple access technique that is used wireless and wireline applications and provides high rate and  quality of service (Qos) data transmission. Increasing the number of users decreases the number of subcarrier per user as result of this, increased bit error rate (BER) of received data and decrease data rate per users in the system because MC-CDMA is a multiuser technology. To overcome this problem, subcarrier allocation algorithms are used. In this work, performances of the subcarrier allocation algorithms are investigated to increase the total rate and fertilisation of the system  for  different numbers of user.

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