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Conference Object Citation - Scopus: 2Miniaturized 2.4 Ghz Antenna Design for Uav Communication Link;(Institute of Electrical and Electronics Engineers Inc., 2020) Yilmaz,V.S.; Kara,A.; Aydin,E.In many communications applications, unlike conventional antennas, lightweight, flexible, small antennas that can adapt to mechanical and industrial constraints are required. In this study, the results of antenna design operating at 2.4 GHz are presented for use in Unmanned Aerial Vehicle (UAV) tele command links. In the parametric and optimization studies carried out on the antenna, it is aimed to increase the gain while keeping the size as small as possible. The requirements of the industry, such as light, aesthetics, miniature and high gain aspects of the antenna were targeted in the design process. Finally, an antenna of 55.2x88 mm size and 7dB gain was achieved using commercial electromagnetic design tools. The designed antenna become satisfying industrial requirements with these features. © 2020 IEEE.Conference Object Citation - Scopus: 11Design of Low-Cost Modular Rf Front End for Rf Fingerprinting of Bluetooth Signals(Institute of Electrical and Electronics Engineers Inc., 2017) Uzundurukan,E.; Ali,A.M.; Kara,A.For RF fingerprinting of wireless devices, data acquisition has a critical role. Because of this, highly sophisticated devices are used for data capturing or acquisition. In this paper, design of a RF receiver front end with modular components is presented. This design contains filtering and down conversion processing of Bluetooth signals for cellular phones. Moreover, AWR VSS and MATLAB have been used for simulating the down converter circuit. With this simulation, effects of components that used in the design on recorded signal have been observed. In this work in progress paper, only high SNR conditions are considered. © 2017 IEEE.Conference Object Citation - Scopus: 1Characterization of satellite transponder impairments based on simulations with test data(Institute of Electrical and Electronics Engineers Inc., 2015) Ulubey,O.; Gulgonul,S.; Kara,A.A satellite transponder simulator based on actual test data of TURKSAT 3A satellite has been developed to analyze degradation in multicarrier scenarios. Communication impairment sources through a transponder are explained in conjunction with a methodology defined to characterize total degradation resulting from them. Several transponder utilization scenarios are studied with respect to total degradation and optimum operation conditions are demonstrated. © 2015 IEEE.Conference Object Citation - Scopus: 2New Wavelet-Based Features for the Recognition of Jittered and Stagger Pri Modulation Types;(Institute of Electrical and Electronics Engineers Inc., 2015) Gencol,K.; Kara,A.; At,N.In dense electronic warfare environments, numerous emitters can be active simultaneously and an interleaved stream of pulses in natural time of arrival order is received by the Electronic Support Measures (ESM) receiver. It is the task of the ESM system to de-interleave this mixed pulse sequence and thus to identify the surrounding threatening emitters. In this processing, pulse repetition interval (PRI) modulation recognition has a significant role due to the fact that it can reveal the hidden patterns inside pulse repetition intervals and thus help identify the emission source and its functional purpose. In this paper, we propose new wavelet-based features for the recognition of jittered and stagger PRI modulation types. The recognition of these types are heavily based on histogram features. Experimental results show that the proposed feature set have very high recognition rates and outperform histogram based methods. © 2015 IEEE.Conference Object Citation - Scopus: 1Analysis of Measurement Instrumentation Delay in Modular Experimental Radar at C Band(Institute of Electrical and Electronics Engineers Inc., 2018) Abdulrazigh,M.Y.A.; Uzundurukan,E.; Kara,A.Unlike pulsed radars, Frequency-Modulated Continuous Wave (FMCW) radar emits continuously very low power levels with the same signal to noise ratio (SNR) of an equivalent pulsed radar. FMCW can measure range and speed of the target. In modular design of such radar, time delay is experienced due to modular components such as low-noise amplifiers (LNA), antennas and, especially, cables. This time delay causes frequency shifts in the measured beat frequency resulting a range measurement error. Therefore, this time delay has to be studied for accuracy of measurements. In this study, experimental results of range measurement errors of a FMCW radar operating at C band are presented. Considering time delay of modular components, a range error of approximately 0.1m was obtained within a range of 10m. © 2018 IEEE.Conference Object Citation - Scopus: 27Improvements on Transient Signal Detection for Rf Fingerprinting(Institute of Electrical and Electronics Engineers Inc., 2017) Ali,A.M.; Uzundurukan,E.; Kara,A.The detection of the transient signal plays a significant role in RF fingerprinting for transmitter devices. This paper proposes modifications on two transient signal detection methods, namely, Bayesian change point detection and phase based detection. For initial tests, Bluetooth signals captured in the laboratory are used for performance analysis of the proposed methods. Preliminary results show that the proposed methods can be used in RF fingerprinting of wireless devices. © 2017 IEEE.Conference Object Citation - Scopus: 2An Experimental Study Towards Examining Human Body Movements in Indoor Wave Propagation at 18-22 Ghz(Institute of Electrical and Electronics Engineers Inc., 2018) Alabish,A.; Kara,A.; Dalveren,Y.As 5G communication may use Millimeter waves (mmWave) bands, it is necessary to evaluate short-range indoor links from the link blockage point of view. This paper presents some initial studies for characterizing effects of human body movements on short range indoor links at 18-22 GHz. Firstly, measurement system is described, and then, calibration measurements along with initial results of the impact of human body movement on the channel are presented for some scenarios. To the best of our knowledge, this study is the first to experimentally examine the effects of human body movements at this band. Yet, as this study constitutes a part of an ongoing research, further results will be anticipated to present the effects of objects over and around the link on the directional propagation at mmWave bands (28-30 GHz). © 2018 IEEE.Conference Object Citation - Scopus: 15Linear Wireless Sensor Networks for Cathodic Protection Monitoring of Pipelines(Institute of Electrical and Electronics Engineers Inc., 2019) Kara,A.; Al Imran,M.A.; Karadag,K.This paper presents design considerations and implementation of linear wireless sensor networks (LWSNs) to be used in cathodic protection (CP) monitoring of oil and natural gas pipelines. Firstly, the paper overviews the CP monitoring system of pipelines. Then, it presents the proposed design of LWSN along with some implementation details by providing high-level design illustrations and system parameters. Moreover, some hardware and software design issues and challenges are addressed briefly. LWSN based CP monitoring system is designed for the use in high rise mountains along with deep valleys, and some other extreme or unattended locations where communication infrastructure is unavailable, or there exists limited or interrupted access to the infrastructure. © 2019 IEEE.Conference Object Citation - Scopus: 6A Mini-Review on Radio Frequency Fingerprinting Localization in Outdoor Environments: Recent Advances and Challenges(Institute of Electrical and Electronics Engineers Inc., 2022) Dogan,D.; Dalveren,Y.; Kara,A.A considerable growth in demand for locating the source of emissions in outdoor environments has led to the rapid development of various localization methods. Among these, RF fingerprinting (RFF) localization has become one of the most promising method due to its unique advantages resulted from the recent developments in machine learning techniques. In this short review, it is aimed to assess the existing RFF methods in the literature for outdoor localization. For this purpose, firstly, the current state of RFF localization methods in outdoor environments are overviewed. Then, the main research challenges in the development of RFF localization are highlighted. This is followed by a brief discussion on the open issues in order to give future research directions. Furthermore, the research efforts currently undertaken by the authors are briefly addressed. © 2022 IEEE.Conference Object Design Considerations for Near To the Ground Communication System and Associated Sub-Ghz Low Profile Antenna(Institute of Electrical and Electronics Engineers Inc., 2017) Yilmaz,V.S.; Bilgin,G.; Aydin,E.; Kara,A.This paper presents propagation aspects of a peer-to peer communication link where antennas are placed near to the ground (low height). First, some of the propagation models are evaluated for understanding of propagation mechanisms. In this regard, as the height of the antennas are very low and the distance is large enough, reflecting angle becomes very small that makes use of two ray model. On the other hand, in the horizontal plane, the positions of the scattering objects, as a source of lateral waves, might vary largely due to the terrain undulations along with variety of objects around the link. This makes propagation mechanisms a little bit complicated. In order to design low profile, high gain sub-GHz antenna for such propagation environment, microstrip antenna with vertical ground was designed and fabricated. The antenna is required to be protected from natural and man-made effects. Therefore, the antenna with associated sensors are embedded into a metal box with a dielectric cover. All these are discussed and some of the findings are presented. © 2017 IEEE.
