Implementation of relay-based systems in wireless cellular networks

Thesis (Master)--Izmir Institute of Technology, Electronics and Communication Engineering, Izmir, 2010Includes bibliographical references (leaves: 69-72)Text in English; Abstract: Turkish and Englishxiii, 72 leavesThe wireless cellular networks are limited by interference and coverage issues where the users at the edge of the cell usually do not receive enough signal energy. To combat these problems and provide higher signal to interference noise ratio and capacity without increasing the transmit power, the idea of using relays in cellular networks was explored and evaluated in the literature. On the other hand, multiple input multiple output (MIMO) antenna systems have great potential to increase capacity and reliability of a wireless cellular network compared to single input single output systems. Hence, the integration of MIMO systems in the relay-based cellular networks has great potential to meet the growing demands of future communication. In this thesis, we explore the performances in conventional and relay-based wireless systems with single and multiple antennas by ad justing the frequency reuse factor as one and four. We consider wireless cellular based networks where six fixed relays are placed evenly in each cell in a hexagonal layout. A user chooses to receive the transmitted signal either directly from the base station or via one of the relays by employing selection algorithms. Throughout this thesis, we first determine the optimum relay locations considering different relay powers. Then, we investigate the system capacity for the cell with and without relays. Next, we examine the capacity performances by changing the cell diameter and the relay power. Finally, we explore the performances of relay based networks with multiple antennas

Implementation of relay-based systems in wireless cellular networks

Thesis (Master)--Izmir Institute of Technology, Electronics and Communication Engineering, Izmir, 2010Includes bibliographical references (leaves: 69-72)Text in English; Abstract: Turkish and Englishxiii, 72 leavesThe wireless cellular networks are limited by interference and coverage issues where the users at the edge of the cell usually do not receive enough signal energy. To combat these problems and provide higher signal to interference noise ratio and capacity without increasing the transmit power, the idea of using relays in cellular networks was explored and evaluated in the literature. On the other hand, multiple input multiple output (MIMO) antenna systems have great potential to increase capacity and reliability of a wireless cellular network compared to single input single output systems. Hence, the integration of MIMO systems in the relay-based cellular networks has great potential to meet the growing demands of future communication. In this thesis, we explore the performances in conventional and relay-based wireless systems with single and multiple antennas by ad justing the frequency reuse factor as one and four. We consider wireless cellular based networks where six fixed relays are placed evenly in each cell in a hexagonal layout. A user chooses to receive the transmitted signal either directly from the base station or via one of the relays by employing selection algorithms. Throughout this thesis, we first determine the optimum relay locations considering different relay powers. Then, we investigate the system capacity for the cell with and without relays. Next, we examine the capacity performances by changing the cell diameter and the relay power. Finally, we explore the performances of relay based networks with multiple antennas

Ege denizinde dağılım gösteren bir sünger türü (Ircinia muscarum Schmidt 1864) ile birlik oluşturan poliketlerin taksonomik ve ekolojik yönden araştırılması

In this study, the taxonomy and ecology of Polychaeta species associated with Ircinia muscarum (SCHMIDT) widely distributed along Turkish Aegean coasts have been investigated. For this purpose, 20 sponge samples from 7 stations laying between Gencelli in the North and Marmaris in the South were collected. As a result of this investigation, 89 polychaeta species belonging to 13 familya have been determined, of which 9 species ( Lepidasthenia elegans, Typosyllis krohni, Typosyllis cir ropunctata, Autolytus pictus, Lysidice collaris, Sclerocheilus minitus, Amphitrite johnstoni, Eupolymnla nebulosa, Oridia armandi) for all Turkish coasts and 9 species (Harmothoe spinifera, Pholoe minuta, Notophyllum foliosum, Syllis gracilis, Typosyllis brevipennis, Trypanosyllis coeliaca, Sphaerosyllis claparedii, Dorvillea rubrovittata, Amphitrite variabilis) for Turkish Aegean coast have been newly reported. Among 13 family associated with Ircinia muscarum, Syllidae ranks first with % 22.4 qualitatively and Nereidae with %22.8 quantitatively. As for the polychaeta species encountered, Ceratonereis costae, Nereis zonata, Typosyllis variegata, Branchiomma bombyx and Polycirrus aurantiacus are having high frequency index values respectively.Bu çalışmada Türkiyenin Ege Denizi sahillerinde geniş dağılım gösteren bir sünger türü (Ircinia muscarum, SCHMIDT) ile birlik oluşturan poliket türleri taksonomik ve ekolojik yönden incelenmiştir. Bu amaçla, kuzeyde Gencelli, güneyde Marmaris arasında toplam 7 istasyondan 20 sünger örneği toplanmıştır. Çalışma sonucunda 13 familyaya ait toplam 89 tür belirlenmiş olup, bunlardan 9 tanesi ( Lepidasthenia elegans, Typosyllis krohni, Typosyllis cirropunctata, Autolytus pictus, Lysidice collaris, Sclerocheilus minitus, Amphi trite johnstoni, Eupolymnia nebulosa, Oridia armandi) tüm Türkiye sahilleri, 9 adedi (Hannothoe spini f era, Pholoe minuta, Notophyllum foliosum, Syllis gracilis, Typosyllis brevipennis, Trypanosyllis coeliaca, Sphaerosyllis claparedil, Dorvillea rubrovittata, Amphi trite variabilis) ise ülkemizin Ege Denizi sahilleri için yeni kayıtlardır. Ircinia muscarum birliğinde kalitatif olarak en baskın familyanın Syllidae (%22.4), kantitatif olarak ise en baskın familyanın Nereidae (%22.8) olduğu saptanmıştır. Poliket türleri arasında sünger birliğinde en bol bulunan 5 tür sırasıyla Ceratonereis costae, Nereis zonata, Typosyllis variegata, Branchiomma bombyx ve Polycirrus aurantiacus olduğu belirlenmişti

İskenderun Körfezi (Levantin Denizi, Doğu Akdeniz) ve civarındaki Eunicidae (Polychaeta) türleri ile Akdeniz için yeni bir yabancı tür ve Lysidice collaris’in yeniden tanımlanması

This study comprises the Eunicidae (Polychaeta) species from İskenderun Bay and surrounding waters (Levantine Sea, Eastern Mediterranean). Benthic material was obtained from 25 stations from 0 to 100 m depths in September 2005. Ten species and 639 individuals belonging to 5 genera were found. Most of the individuals (65%) were determined among rocks and algae. Palola valida for the Mediterranean Sea, Eunice antennata and Lysidice margaritacea for the Levantine Sea, and E. vittata, Marphysa bellii, and M. sanguinea for the Levantine coast of Turkey are new records. Eunice antennata and P. valida were introduced from the Red Sea and appear to have been well established in the area, constituting 57% of eunicids inhabiting crevices of rocks. Lysidice collaris is re-described on the basis of type material, and E. antennata, L. margaritacea, and P. valida are fully described

SAROS KÖRFEZİ’NDE DAĞILIM GÖSTEREN LONGOSOMATIDAE VE SPIONIDAE (ANNELIDA: POLYCHAETA) TÜRLERİNİN TAKSONOMİK VE EKOLOJİK ÖZELLİKLERİ

Ege Denizi'nin Kuzey Doğusunda yer alan Saros Körfezi'nde dağılım gösteren Longosomatidae ve Spionidae (Annelida: Polychaeta) türlerinin taksonomik ve ekolojik özelliklerini saptamak amacıyla yapılan bu çalışmada, derinlikleri 8 ile 680 metre arasında değişen 18 istasyondan bentik örnekler alınmıştır. Bu bentik örneklerden elde edilen poliket bireylerinin incelenmesi sonucunda 2 familyaya (Longosomatidae, Spionidae) ait 11 genus, 17 tür ve toplam 927 birey tespit edilmiştir. Bu türlerden Spiophanes mediterraneus, Ege Denizi ve Türkiye poliket faunası için; Heterospio mediterranea ise Türkiye poliket faunası için yeni kayıtlardır. Bu çalışmada en fazla tür Posidonia oceanica ve çamurlu dip yapısına sahip 5 ve 11 nolu istasyonlarda, en az tür ise bölgedeki en derin istasyonlarda (17 ve 18) tespit edilmiştir. En fazla bireye kumlu çamurlu dip yapısına sahip 10 nolu istasyonda (175 birey), en az bireye ise P. oceanica'lı dip yapısına sahip 13 (13 birey), 15 (17 birey) ve 3 (18 birey) nolu istasyonlarda rastlanılmıştırIn order to determine the taxonomic and ecological characteristics of Longosomatidae and Spionidae (Annelida: Polychaeta) species distributed in Saros Bay situated in the north east of the Aegean Sea, benthic samples were taken from 18 stations having depth ranges 8-680 m. As a result of evaluating these samples, 11 genus, 17 species and 927 individuals belonging to 2 families (Longosomatidae and Spionidae) have been identified. Among them, Spiophanes mediterranus is a new record for the Aegean Sea and Turkish Polychaete fauna and Heterospio mediterranea is a new record for Turkish Polychaete fauna. In this study, the highest number of species were encountered at station 5 which has Posidonia oceanica meadows and at station 11 represented with muddy bottom while few number of species were determined at the deepest stations (17 and 18). The maximum number of individuals (175) were found at station 10 with sandy mud bottom, while the minimum number of individuals were determined at stations (Station 13: 13 individuals; Station 15: 17 individuals; Station 3: 18 individuals) with P. oceanica meadows