Frekans ve zaman bölgesi kanal denkleştiricili OFDM sistemlerinin kodlamasız ve katlamalı kodlanmış başarımlarının karşılaştırılması

Bu çalışmada, frekans ve zaman bölgesi kanal denkleştiricili OFDM sistemlerinin kodlamasız ve katlamalı kodlama kullanılması durumunda BER başarımları karşılaştırılmaktadır. Benzetimler, Rayleigh sönümlemeli frekans seçici kanallar üzerinden gerçekleştirilmiştir. Elde edilen sonuçlar, gürültünün etkin olduğu bölgede zaman bölgesi kanal denkleştiricili sistemin, ISI’ın etkin olduğu bölgede ise frekans bölgesi kanal denkleştiricili sistemin başarımının daha yüksek olduğunu göstermiştir. Ayrıca, katlamalı kodlama tekniğinin, zaman bölgesi kanal denkleştiricili sistemin hata eşiğini aşağı çektiği, fakat ortadan kaldıramadığı belirlenmiştir.

Performance comparison of uncoded and convolutional coded OFDM systems with frequency and time domain channel equalizer

In this study, BER performances of uncoded and convolutional coded OFDM systems with frequency and time domain channel equalizer are compared. Simulations are carried out through Rayleigh faded frequency selective channels. The results obtained show that the system with time domain channel equalizer exhibits better performance in the noise limited region while the performance of the system with frequency domain channel equalizer is better in ISI limited region. It is also observed that convolutional coding technique has reduced error floor of the system with time domain channel equalizer, but has not removed it totally.

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