http://hdl.handle.net/20.500.12416/260 Elektronik ve Haberleşme Mühendisliği Bölümü yayınlarını içerir. Wed, 28 Oct 2026 19:57:09 GMT 2026-10-28T19:57:09Z http://hdl.handle.net/20.500.12416/8309 The Research and Design of Multi Relays in Cooperative Communication System Based on Polar Codes Hadi Hadı, Ali Sameer; Gazi, Orhan In this paper, we propose a method to increase the performance of cooperative communication using polar codes. For this purpose, we consider non-line-of sight (NLOS) cooperative communication scheme where destination node does not receive signal from source directly. The relay nodes use decodes and forward approach. We propose a voting scheme for the relay nodes, which share information among them. It is shown by the simulation results that the proposed approach significantly improves the performance of relayed communication. Fri, 01 Jan 2021 00:00:00 GMT http://hdl.handle.net/20.500.12416/8309 2021-01-01T00:00:00Z http://hdl.handle.net/20.500.12416/8197 Prunable collision free random interleaver design Gazi, Orhan In this article we introduce a new collision free prunable random interleaver. The suggested interleaver is a joint structure involving rectangular and S-random interleaver. It comprises a general model for all kind of collision free prunable random interleavers. In addition, it can be designed for any number of parallel processors and any length of information sequence vector and can be considered also as a template for collision free prunable interleavers. The proposed interleaver can be used with all kind of turbo-like codes. The performance of the proposed interleaver is measured with parallel decodable serially concatenated convolutional codes (PDSCCCs) and compared to the PDSCCCs' performance with collision full S-random interleaver. Wed, 01 Aug 2012 00:00:00 GMT http://hdl.handle.net/20.500.12416/8197 2012-08-01T00:00:00Z http://hdl.handle.net/20.500.12416/8161 Performance Analysis Of Optical Spherical Wave İn Biological Tissue Altay Arpali, Serap In this study, bit error rate (BER) of optical spherical wave is investigated to analyze the performance of spherical wave through in soft tissue. Within this scope, average BERs (<BER>) of optical spherical wave are extensively examined depends on the different tissue and turbulence parameters that are random changes in the refractive index of the soft tissue, the tissue length from source to receiver, and the outer scale of the tissue turbulence. It is observed from the outputs that the (<BER>) increases with increasing value of outer scales, tissue lengths and random changes in the refractive index of the soft tissue. Also we investigated (<BER>) values of the optical spherical wave for the different values of the one half of the quantified slope in the range of power-law scaling. It is found that smaller <BER>s of the spherical wave are obtained for decreasing values of one half of the quantified slope in the range of power-law scaling. Fri, 31 Dec 2021 00:00:00 GMT http://hdl.handle.net/20.500.12416/8161 2021-12-31T00:00:00Z http://hdl.handle.net/20.500.12416/8050 Odak Dışı Beslemeli Silindirik Parabolik Reflektör Antenlere Ait Işıma İntegralinin Optimizasyonu Yalçın, Uğur; Umul, Yusuf Ziya Bu çalışmada, ( , ,z ρ 0 φ0 ) koordinatlarına yerleştirilmiş çizgisel akım kaynağıyla beslenen, z eksenine paralel sonsuz uzun mükemmel iletken içbükey silindirik parabolik reflektör antenden saçılma problemi göz önüne alınmıştır. İlk olarak, Hertz vektörüne ait yüzey ışıma integrali Fiziksel Optik (FO) yöntemi kullanılarak belirlenmiştir. Bu integral ifadesin de görülen Green fonksiyonu tanımlanmış ve yüzeye ait normal birim vektörü ile yüzeye gelen toplam magnetik alan bileşeninin vektörel çarpımı elde edilmiştir. Daha sonra bu ifadeler ışıma integralinde yerine yazılmış ve integralin ' z katı hesaplanmıştır. Neticede, FO ışıma integrali sadece ' φ katına bağlı olarak ifade edilebilmiştir. Elde edilen integral ifadesinden faydalanılarak anten sistemine ait ışıma diyagramları, ilgili parametrelerin çeşitli değerleri için polar koordinatlarda çizdirilmiş ve böyle bir anten sisteminin tasarımı için en optimum durum araştırılmıştır. Çalışmada silindirik parabolik reflektör antenin çalışma frekansı 2 (GHz) olarak seçilmiştir Sat, 01 Jan 2005 00:00:00 GMT http://hdl.handle.net/20.500.12416/8050 2005-01-01T00:00:00Z