Elektronik ve Haberleşme Mühendisliği Bölümü Yayın Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/260
Browse
3 results
Search Results
Article Citation - WoS: 2Citation - Scopus: 2Ber Anaylsis for Super Lorentz-Gaussian Laser Beams Propagating in Turbulent Media(Gazi Univ, Fac Engineering Architecture, 2013) Gokce, Muhsin C.; Gökçe, Muhsin Caner; Sari, Filiz; Ozek, Faruk; Elektronik ve Haberleşme MühendisliğiIn this work, BER-SNR variation of super Lorentz-Gaussian laser beam that propagating horizontally path in turbulent media is analyzed. Using scintillation index which is obtained by extented Huygens-Fresnel principle, BER - SNR value is calculated. Matlab program is used to show BER - SNR variation depending on link distance and beamwidth. To conclude, in short link range, super Lorentz-Gaussian beam is proven to be better link performance superior to commercially available Gaussian beam.Article Investigation of Factors Affecting Noise Robustness in Voice Activity Detectors(Gazi Univ, Fac Engineering Architecture, 2023) Ozaydin, SelmaIn this manuscript, some voice activity detectors (VADs) in the literature were examined in terms of factors affecting their robustness under different acoustic noise conditions and in this context, the changes in detection accuracy rates according to changing noise conditions were tested. In this scope, the effect of situations such as whether the threshold value used in the decision phase in VAD methods is fixed or adaptive, the analysis window is short or long, the use of more than one feature vector together has been evaluated and analyzed comparatively. While three of the four different VAD detectors examined in this manuscript use feature vectors within the short-term analysis window while generating the decision result, one decides according to the measurement result of long-term spectral vectors. The VAD detectors in the article have been tested using the NOIZEUS noisy speech database. Thus, the performance of the analyzed VADs has been evaluated under different acoustic conditions using an extensive database that has already taken place in the literature. During the testing of the analyzed VADs, different input noise speech signals with environmental background noises between [15-0dB] such as restaurant, car, street, or station were tested. Tests were carried out using objective test measurement methods and the detection accuracy rate of each VAD method was measured. The results showed that each method gave different endurance performance in adverse environmental conditions.Article Türbülanslı ortamda yayılan super Lorentz-Gauss laser demetleri için ber analizi(Gazi Univ, Fac Engineering Architecture, 2013) Gökçe, Muhsin Caner; Sarı, Filiz; Özek, FarukÇalışmada, türbülanslı ortamda yayılan super Lorentz-Gauss laser demetlerinin yatay iletim uzaklıklarındaki BER - SNR değişimi hesaplandı. BER hesaplamalarında kullanılan pırıldama indisleri, genişletilmiş HuygensFresnel prensibi ile elde edilmiştir. Matlab kullanılarak BER – SNR değerinin bağlantı uzaklığına ve laser kaynak boyutuna bağımlılığı gösterildi. Kısa iletim mesafesinde super Lorentz-Gauss laser demetinin ticari olarak kullanılan Gauss laser demetine göre daha iyi bağlantı performansı sağladığı sonucuna varıldı.