WOLA-OFDM sisteminde tepe gücü/ortalama güç oranının düşürülmesi için yeni bir SLM şeması

Öz

Bu makale, yakın zamanda bulunan ağırlıklı örtüştürme ve ekleme-dikgen frekans bölmeli çoğullama (WOLA-OFDM) sistemindeki yüksek tepe gücü/ortalama güç oranı (PAPR) sorununu ele almaktadır. OFDM tabanlı çok taşıyıcılı iletim stratejilerinde en yaygın kullanılan PAPR düşürme şemalarından biri olan seçici eşleme (SLM), WOLA-OFDM sinyallerinin PAPR değerini düşürmek için kullanılabilir. Ancak, WOLA-OFDM vericisinde sembol uzantılarının örtüşmesi, SLM’nin performansını önemli ölçüde kötüleştirmektedir. Bu sorunun üstesinden gelmek amacıyla, WOLA-OFDM sistemi için, çift sembol optimizasyon tabanlı SLM (DSO-SLM) isimli etkili bir SLM şeması geliştirdik. Bu yeni şemada, geleneksel SLM’de olduğu gibi komşu sembollerin PAPR değerini ayrı ayrı düşürmek yerine, PAPR değeri minimize edilmiş optimum iletim sinyali aranırken her bir sembol, kendisiyle örtüşen bir önceki sembol ile birlikte değerlendirilmektedir. DSO prosedürünün kullanımıyla birlikte, geleneksel SLM’nin WOLA-OFDM sistemindeki performansını artırmak mümkün hale gelmektedir.

Anahtar Kelimeler

• PAPR
• Seçici Eşleme
• WOLA-OFDM
• Çift Sembol Optimizasyonu
• 5G

A novel SLM scheme for peak-to-average power ratio reduction in WOLA-OFDM system

Öz

This paper addresses high peak-to-average power ratio (PAPR) issue in the recently invented weighted overlap and add-orthogonal frequency division multiplexing (WOLA-OFDM) system. The selective mapping (SLM), one of the most widely used PAPR reduction schemes in OFDM-based multicarrier transmission strategies, can be used to reduce the PAPR of WOLA-OFDM signals. However, the overlapping of symbol extensions in the WOLA-OFDM transmitter considerably deteriorates the performance of SLM. To overcome this problem, we have developed an efficient SLM scheme named dual symbol optimization-SLM (DSO-SLM) for the WOLA-OFDM system. In this new scheme, instead of reducing the PAPR of adjacent symbols separately as in conventional SLM, each symbol is evaluated together with its overlapping predecessor symbol while searching for the optimal transmission signal with minimized PAPR. With the usage of DSO procedure, it becomes possible to enhance the performance of conventional SLM in the WOLA-OFDM system.

Anahtar Kelimeler

• PAPR
• Selective Mapping
• WOLA-OFDM
• Dual Symbol Optimization
• 5G

Kaynakça

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