Gökdoğan, Bengisu Yalçınkaya
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Name Variants
Gökdoğan,B.Y.
G., Bengisu Yalçınkaya
G.,Bengisu Yalçınkaya
Gökdoğan B.
G., Bengisu Yalcinkaya
Gokdogan B.
B.,Gökdoğan
G.,Bengisu Yalcinkaya
Bengisu Yalcinkaya, Gokdogan
Gokdogan, Bengisu Yalcinkaya
B. Y. Gokdogan
Bengisu Yalçınkaya, Gökdoğan
B. Y. Gökdoğan
B.Y.Gökdoğan
Yalcinkaya B.
Gökdoğan, Bengisu Yalçınkaya
Gokdogan,B.Y.
B.Y.Gokdogan
Yalcinkaya, Bengisu
B., Gokdogan
G., Bengisu Yalçınkaya
G.,Bengisu Yalçınkaya
Gökdoğan B.
G., Bengisu Yalcinkaya
Gokdogan B.
B.,Gökdoğan
G.,Bengisu Yalcinkaya
Bengisu Yalcinkaya, Gokdogan
Gokdogan, Bengisu Yalcinkaya
B. Y. Gokdogan
Bengisu Yalçınkaya, Gökdoğan
B. Y. Gökdoğan
B.Y.Gökdoğan
Yalcinkaya B.
Gökdoğan, Bengisu Yalçınkaya
Gokdogan,B.Y.
B.Y.Gokdogan
Yalcinkaya, Bengisu
B., Gokdogan
Job Title
Araştırma Görevlisi
Email Address
bengisu.yalcinkaya@atilim.edu.tr
ORCID ID
Scopus Author ID
Turkish CoHE Profile ID
Google Scholar ID
WoS Researcher ID
Scholarly Output
10
Articles
6
Citation Count
12
Supervised Theses
0
10 results
Scholarly Output Search Results
Now showing 1 - 10 of 10
Conference Object Citation Count: 2An Experimental Study on the Influence of Human Movement in Indoor Radio Channel at 28GHz(Ieee, 2021) Benzaghta, Mohamed; Gökdoğan, Bengisu Yalçınkaya; Coruk, Remziye Busra; Yalcinkaya, Bengisu; Çoruk, Remziye Büşra; Kara, Ali; Electrical-Electronics Engineering; Department of Electrical & Electronics EngineeringHuman activities around the communication link in an indoor environment have a significant impact on millimeter-wave (mmWave) communication systems, which are used for the new generation of communication networks (5G). Therefore, it is essential to evaluate short range indoor links from the link blockage point of view. This paper presents the propagation measurements in the presence of human activity, for a short range indoor office environment communication link at 28 GHz. During the experimental measurements, the human activity of three and six persons were observed for three different antenna height combinations. The human blockage (shadowing effect) is characterized in terms of the shadowing event duration, temporal fading, as well as overall attenuation. The results reported by this experimental study is believed to be vital in designing future mmWave communication systems that can overcome the deep fades caused by human blockage in short indoor communication links. Yet, this paper constitutes a part of an ongoing research study, further detailed results will be foreseen to present the precise effect of human movements around the propagation link at 28GHz.Article Citation Count: 0Blockage loss and shadow fading behavior of millimeter-wave signals due to human bodies at 28 GHz(Wiley, 2024) Gökdoğan, Bengisu Yalçınkaya; Gokdogan, Bengisu Yalcinkaya; Çoruk, Remziye Büşra; Kara, Ali; Electrical-Electronics Engineering; Department of Electrical & Electronics EngineeringAs the millimeter-wave (mm-Wave) spectrum is considered to be an essential enabler to the fifth generation (5G) wireless communication systems. Human movements are one of the most significant factors that cause transient blockage in indoor mm-wave channels. In this letter, human blockage measurements and shadow fading statistics due to human body movements in an indoor office environment are reported for the 28 GHz band. The effect of human bodies on the channel is measured for several scenarios including a variety of population and using diverse antenna heights. The reported shadow fading statistics include both the duration and the depth of the blockage fade, and accordingly, we propose several empirical models that cater for such blockage events. The findings reported in this letter could improve the modeling of indoor radio channels at 28 GHz bands by considering the presence of humans, as well as their movements.Conference Object Citation Count: 1Low Radar Cross Section UAV Design in X-Band;(Institute of Electrical and Electronics Engineers Inc., 2022) Aydın, Elif; Sezgin,S.; Gökdoğan, Bengisu Yalçınkaya; Gokdogan,B.Y.; Aydin,E.; Department of Electrical & Electronics Engineering; Electrical-Electronics EngineeringAs Unmanned Aerial Vehicles (UAVs) have become widespread in defense industry, the radar technology that can detect them has also improved. These improvements cause UAVs to be detected more easily, which limits their effectiveness in military usage. Although the reduction of the radar cross-section (RCS) can provide a solution to this issue, the studies regarding that is insufficient in the literature. In this study, a shaping method is recommended to reduce the RCS of UAVs, and it is shown the method is effective to address the problem. Firstly, using a simulation tool, an UAV model is designed from simple shapes and the model is validated by comparing it with the ones in literature. Secondly, RCS values are measured using vertical and horizontal polarization throughout 360 degrees by incrementing the aspect angle by one degree in X-Band using the CST Studio Suite environment. Then, considering the hardware and aerodynamic requirements as well as limitations of the UAV model, a shaping technique is applied to the body, legs and the hollow parts of the UAV model with parametric simulations. The results show that the recommended shaping technique can provide a significant reduction in the RCS of an UAV. © 2022 IEEE.Article Citation Count: 0A Hybrid-Flipped Classroom Approach: Students' Perception and Performance Assessment(Univ Nac Colombia, Fac ingenieria, 2023) Gökdoğan, Bengisu Yalçınkaya; Coruk, Remziye Busra; Çoruk, Remziye Büşra; Kara, Ali; Electrical-Electronics Engineering; Department of Electrical & Electronics EngineeringThis study presents an improved hybrid-flipped classroom (hybrid-FC) education method based on technology-enhanced learning (TEL) along with diluted classes for a course on probability and random processes in engineering. The proposed system was implemented with the participation of two student groups who alternated weekly between attending face-to-face activities and fully online classes as a sanitary measure during the pandemic. The education model was combined with the flipped classroom (FC) approach in order to improve the quality of learning and address the negative effects of remote education. Before the lessons, the students studied the course material, filled a question form, and then took a low- stake online quiz. Then, the students attended a session where the questions reported in the forms were discussed, and they took an online problem-solving session followed by an individual quiz. Class sessions were available to both online and face-to-face students, as well as in the form of video recordings for anyone who missed lessons. Qualitatively and quantitatively, the proposed education method proved to be more effective and comprehensive than conventional online methodologies. The students' performances were evaluated via quizzes and exams measuring the achievement of the course learning outcomes ( CLOs). Weekly pre/post-tests were applied to examine the students' progress in each topic. Midterm and final exams were planned to measure the level of success for all course topics. Additionally, the students' perception was assessed with questionnaires and face-to-face interviews. A performance assessment showed an apparent increase in the success rate, and the students' perception was found to be positive.Conference Object Citation Count: 0Radar Cross Section Studies of Low Signature UAVs in X-Band: Simulation, Measurement and Performance Evaluation;(Institute of Electrical and Electronics Engineers Inc., 2024) Aydın, Elif; Gökdoğan,B.Y.; Gökdoğan, Bengisu Yalçınkaya; Department of Electrical & Electronics Engineering; Electrical-Electronics EngineeringIn this study, the effectiveness of a radar cross section (RCS) reduction method based on a proposed shaping technique for four-legged unmanned aerial vehicles (UAV) has been proven with simulation tools and experimental measurements in X-Band. Simulative RCS values were obtained with CST and HFSS electromagnetic calculation tools, and the advantages of these tools compared to each other were examined. Experimental measurements were carried out in a laboratory environment with a vector network analyzer (VNA) and confirmed with simulation results. The effects of frequency, polarization and aspect angle factors on RCS were examined. It has been shown that with the proposed measurement method, low-cost and easily applicable RCS analysis can be performed in X-Band, one of the frequency bands frequently used in the defense industry. With the proposed shaping method, RCS reduction in the range of 5-10 dBsm was achieved. © 2024 IEEE.Conference Object Citation Count: 1UAV Detection and Ranging with 77-81 GHz FMCW Radar;(Institute of Electrical and Electronics Engineers Inc., 2022) Çoruk, Remziye Büşra; Aydın, Elif; Demir,E.C.; Gökdoğan, Bengisu Yalçınkaya; Gokdogan,B.Y.; Aydin,E.; Department of Electrical & Electronics Engineering; Electrical-Electronics EngineeringIn this study, detection of unmanned aerial vehicles (UAV), determination of radar cross-section (RCS) values, and range estimation were performed using a commercial off-the-shelf (COTS) millimeter-wave Frequency Modulated Continuous Wave (mmWave FMCW) radar system in the 77-81 GHz frequency band. The measurements were carried out in a laboratory environment using a single transceiver antenna without the need for an anechoic chamber. RCS values of different vertically and horizontally positioned UAVs were measured experimentally along the 360o aspect angle, and the simulated results obtained from computational tool were compared with the experimental results. The measurement and simulation results, together with the range estimation, matched with high accuracy. © 2022 IEEE.Article Citation Count: 5On the design and effectiveness of Simulink-based educational material for a communication systems course(Wiley, 2020) Coruk, R. Busra; Gökdoğan, Bengisu Yalçınkaya; Yalcinkaya, Bengisu; Kara, Ali; Kara, Ali; Electrical-Electronics Engineering; Department of Electrical & Electronics EngineeringThe methods used in engineering education have gained diversity in parallel with rapidly evolving technology. New technological methods along with the traditional methods have been adopted for undergraduate education. Today, Simulink-based educational materials are used in many fields in engineering education. However, in the literature, the contribution of such educational materials to the learning process has not been measured thoroughly. This study presents a comprehensive measurement method to improve the created course material and show the effectiveness of developed course material in students' success. First, educational material was developed for an undergraduate electrical engineering course: communication systems. A feedback group made up of diverse student learners was employed extensively in the material development phase. Next, the impact of the developed material on the success of the students was examined using both qualitative and quantitative measurement tools including questionnaires, one-to-one interviews, and class and university level anonymous surveys. This also included students' performance regarding laboratory quizzes and achievement of course learning outcomes. Overall, the measurement results show that the course material increased students' success in the course. Moreover, students' general perception of the course material was positive.Article Citation Count: 2Modeling and measurement of human body blockage loss at 28 GHz(Taylor & Francis Ltd, 2023) Gökdoğan, Bengisu Yalçınkaya; Gokdogan, Bengisu Yalcinkaya; Çoruk, Remziye Büşra; Kara, Ali; Electrical-Electronics Engineering; Department of Electrical & Electronics EngineeringMillimeter-wave (mm-Wave) spectrum is an essential enabler to the fifth generation (5G) wireless technology. Humans are one of the most noticeable blockers that cause temporal variation in indoor radio channels. This paper presents human blockage measurements at 28 GHz, with several humans of different sizes. The effect of the crossing orientations of the human bodies is investigated for three different transmitter heights. A human blockage model based on the Fresnel diffraction scheme is shown to be applicable in estimating the human blockage loss in indoor radio links considering various body sizes, different crossing orientations, and different transmitter heights. The findings reported in this paper could help improve indoor radio channel models at 28 GHz bands for 5G technologies considering the presence of human body blockages.Article Citation Count: 1On the Classification of Modulation Schemes Using Higher Order Statistics and Support Vector Machines(Springer, 2022) Gökdoğan, Bengisu Yalçınkaya; Gokdogan, Bengisu Yalcinkaya; Çoruk, Remziye Büşra; Kara, Ali; Electrical-Electronics Engineering; Department of Electrical & Electronics EngineeringThe recognition of modulation schemes in military and civilian applications is a major task for intelligent receiving systems. Various Automatic Modulation Classification (AMC) algorithms have been developed for this purpose in the literature. However, classification with low computational complexity as well as reasonable processing time is still a challenge. In this paper, a feature-based approach along with various classifiers is employed based on statistical features as well as higher-order moments and cumulants. An over-the-air (OTA) recorded dataset consisting of four analog and ten digital modulation schemes are used for testing the proposed method at 0-20 dB SNR. The overall accuracy for quadratic Support Vector Machine (SVM) is found to be as high as 98% at 10 dB. The comparison of the results with other AMC papers published in the literature indicates that the proposed method present higher accuracy, especially for realistic channel induced OTA dataset.Article Citation Count: 0Hierarchical Classification of Analog and Digital Modulation Schemes Using Higher-Order Statistics and Support Vector Machines(Springer, 2024) Gökdoğan, Bengisu Yalçınkaya; Coruk, Remziye Busra; Çoruk, Remziye Büşra; Kara, Ali; Tora, Hakan; Electrical-Electronics Engineering; Airframe and Powerplant Maintenance; Department of Electrical & Electronics EngineeringAutomatic modulation classification (AMC) algorithms are crucial for various military and commercial applications. There have been numerous AMC algorithms reported in the literature, most of which focus on synthetic signals with a limited number of modulation types having distinctive constellations. The efficient classification of high-order modulation schemes under real propagation effects using models with low complexity still remains difficult. In this paper, employing quadratic SVM, a feature-based hierarchical classification method is proposed to accurately classify especially higher-order modulation schemes and its performance is investigated using over the air (OTA) collected data. Statistical features, higher-order moments, and higher-order cumulants are utilized as features. Then, the performances of some well-known classifiers are evaluated, and the classifier presenting the best performance is employed in the proposed hierarchical classification model. An OTA dataset containing 17 analog and digital modulation schemes is used to assess the performance of the proposed classification model. With the proposed hierarchical classification algorithm, a significant improvement has been achieved, especially in higher-order modulation schemes. The overall accuracy with the proposed hierarchical structure is 96% after 5 dB signal-to-noise ratio value, approximately a 10% increase is achieved compared to the traditional classification algorithm.
