Browsing Elektrik ve Elektronik Mühendisliği Bölümü / Department of Electrical & Electronics Engineering by Issue Date
Now showing items 1-20 of 292
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Constellation rearrangement for 4-PAM repetition coding
(IEEE, 2014)In fading channels to get diversity gain, transmitted data can be repeated in time or frequency. Constellation reaarangement can be used instead of using the same signal constellation for each repeated transmission. In ... -
Polarization independent nanobeam cavity tuning using annular photonic crystals
(SPIE, 2014)Nanobeam cavity waveguides have drawn great attention of the researchers due to being a useful optical platform for several applications, e. g. optical switching and filtering.1 Almost all of the past studies investigated ... -
Broadband directional cloaking using graded index structures
(IEEE Computer Society, 2014)We propose broadband two-dimensional cloaking designs based on isotropic and all dielectric lossless materials. The photonic structures are created by implementing artificially generated graded index (GRIN) media. The ... -
Enhanced sub-wavelength focusing by tilted and modified graded index medium
(Institute of Electrical and Electronics Engineers Inc., 2014)The inhomogeneous variation of index distribution as graded index (GRIN) medium focuses light without the curved surfaces. In the current study, we investigate enhanced focusing properties of GRIN medium with tilted front ... -
Compact rainbow trapping and demultiplexing by photonic crystal waveguides
(Institute of Electrical and Electronics Engineers Inc., 2014)Graded Index Photonic Crystals (GRIN PhCs) are artificial periodic materials that possess gradually varying effective refractive indices. GRIN profiles can be formed by adjusting the radii or the locations of PhC unit ... -
Asymmetric transmission from a 2D PT-symmetric honeycomb nanostructure
(IEEE Computer Society, 2014)We propose a simple realization of a 2-dimensonal (2D) PT-symmetric photonic structure: a honeycomb arrangement of alternating cylinders with gain or loss in a dielectric background. The structure provides a periodic ... -
Application of Data Acquisition System for Superconducting Quantum Interface Devices (SQUID) at Remote Location
(IEEE Computer Society, 2014)Together with technological developments related to the specific area, the scope of remote data acquisition systems has become widened. The usages of these kinds of systems prevent waste of time and labor. Therefore, in ... -
Spectrum Sharing in Radar and Wireless Communication Systems: A Review
(IEEE, 2014)The idea of spectrum sharing between radar and wireless communication systems arise because of the need for extra bandwidth for wireless communication systems. Due to strong and ever growing economic, political, social, ... -
The Impact of Random Power Assignment in Handshaking on Wireless Sensor Network Lifetime
(IEEE, 2014)Optimization of data and acknowledgement (ACK) packets' transmission power levels is necessary to prolong the lifetime of wireless sensor networks (WSNs). Utilizing the maximum power level available results in the minimum ... -
The Impact of Near-Ground Path Loss Modeling on Wireless Sensor Network Lifetime
(IEEE Computer Society, 2014)Network lifetime is the ultimate objective in evaluating the performance of Wireless Sensor Networks (WSNs). To assess the network lifetime correctly for a particular WSN deployment, utilizing realistic abstractions for ... -
Diversity Analysis of Hierarchical Modulation in Cooperative Communication
(IEEE, 2014)In cooperative communication systems, hierarchical modulation is used to increase systems robustness and to send different information flows simultaneously. In cooperative communication systems which use hierarchical ... -
Maximum-Weight Scheduling with Hierarchical Modulation
(IEEE, 2014)In this paper, hierarchical modulation is used in conjunction with maximum-weight scheduling to achieve lower transmission delays. Via hierarchical modulation, the scheduled user has the option to transmit to two users ... -
Trade-offs in Sum-Rate Maximization and Fairness in Relay-Enhanced OFDMA-based Cellular Networks
(IEEE, 2014)Routing, subchannel scheduling, and power allocation are generally treated as separate problems in relay-enhanced OFDMA-based cellular networks. They are mostly modeled using non-linear constraints to maximize either sum ... -
Data Packet Length Optimization for Wireless Sensor Network Lifetime Maximization
(IEEE, 2014)Wireless Sensor Networks (WSNs) comprising of battery-powered sensor nodes are being used in a wide range of applications. The feasibility of such applications is highly influenced by the longevity of these networks. In ... -
Design of RSFQ wave pipelined Kogge-Stone Adder and developing custom compound gates
(Elsevier Sci Ltd, 2014)Since the invention of computers, the calculation of arithmetic and logic operations using digital circuits has been one of the leading problems in processor designs. The challenge has been to compute more operations with ... -
Theoretical and experimental investigations of asymmetric light transport in graded index photonic crystal waveguides
(2014-01)To provide asymmetric propagation of light, we propose a graded index photonic crystal (GRIN PC) based waveguide configuration that is formed by introducing line and point defects as well as intentional perturbations inside ... -
Partial cloaking by graded index photonic crystals
(SPIE, 2014-04)Since the first proposal of the idea of optical cloaking, huge research effort has been spent to implement hiding objects. We propose a broad band all-dielectric partial (unidirectional) cloaking device that hides arbitrary ... -
Influence of excitation frequency on structural and electrical properties of spray pyrolyzed CuInS2 thin films
(Elsevier Science Sa, 2014-06)This paper reports the cost effective deposition of the copper indium sulfide (CuInS2) thin films under atmospheric conditions via ultrasonic spray pyrolysis. Structural and electrical properties of these films have been ... -
Diversity Analysis of Hierarchical Modulation in Wireless Relay Networks
(IEEE-Inst Electrical Electronics Engineers Inc, 2014-07)In communication systems, hierarchical modulation is used to increase system robustness and to send different information flows simultaneously. However, when used in cooperative communication systems, hierarchical modulation ... -
Design and Optimization of Fully Digital SQUID Based on Bi-Directional RSFQ
(Springer, 2014-07)Bi-directional RSFQ benefits from using both positive and negative SFQ pulses to manipulate and transfer digital data. This allows more flexibility in the design of simpler circuits with enhanced performance. On the other ...
