Feza Kerestecioğlu

Kerestecioğlu, Feza

Name Variants

Kerestecioglu F.
K., Feza
Feza Kerestecioğlu
Kerestecioğlu F.
Kerestecioǧlu F.
Kerestecioglu,F.
FEZA KERESTECIOĞLU
Kerestecioğlu, F.
Kerestecioğlu,F.
KERESTECIOĞLU, Feza
KERESTECIOĞLU, FEZA
K.,Feza
Feza KERESTECIOĞLU
Kerestecioğlu, FEZA
Feza, Kerestecioglu
Kerestecioglu,Feza
F. Kerestecioğlu
Kerestecioglu, Feza
Kerestecioğlu, Feza
Keresteci˙oğlu,F.
Kerestecioglu, F.

Job Title

Prof. Dr.

Email Address

kerestec@khas.edu.tr

ORCID ID

0000-0001-9722-9458

Scopus Author ID

6603417688

Full item page

Scholarly Output

24

Articles

10

Citation Count

70

Supervised Theses

1 Scholarly Output Search Results

Now showing 1 - 10 of 24

Indoor Positioning Using Federated Kalman Filter
(IEEE, 2018) Aybakan, Tarik; Kerestecioğlu, Feza; Kerestecioglu, Feza
In this paper, the performance of a multi-sensor fusion technique, namely Federated Kalman Filter (FKF) is studied in the context of indoor positioning problem. Kalman filters having centralized and decentralized structures are widely used in outdoor positioning and navigation applications. Global Positioning System (GI'S) is the most commonly used system for outdoor positioning/navigation, which cannot be used indoors due to the signal loss. In this study, a decentralized structure for FKF is applied in indoor positioning problem by taking its outdoor navigation performance into consideration. Simulations are perl4med with distance measurements, which are assumed to be calculated by using Received Signal Strength (RSS). Results gathered via different simulations are evaluated as promising for future studies.
Circular Formations of Non-Communicating Robot Groups Via Local Strategies
(Sage Publications Ltd, 2023) Kerestecioglu, Feza; Kerestecioğlu, Feza; Sen, Uemit; Isikver, Cagri; Goktekin, Ahmet
Local strategies, which are based on cost minimization, to achieve circular formations of autonomous robot groups are presented. It is assumed that the group members have no communication capabilities or any means of interchanging information among themselves, and that they can only rely on their sensors, which provide relative positions of their nearby group members. It is verified on simulations that via appropriately defined cost functions arc, arc-triangle and circle formations are obtained, which can be maintained during navigation.
Indoor Positioning Using Federated Kalman Filter
(Institute of Electrical and Electronics Engineers Inc., 2018) Ayabakan, Tarık; Kerestecioğlu, Feza; Kerestecioğlu, Feza
In this paper, the performance of a multi-sensor fusion technique, namely Federated Kalman Filter (FKF) is studied in the context of indoor positioning problem. Kalman filters having centralized and decentralized structures are widely used in outdoor positioning and navigation applications. Global Positioning System (GPS) is the most commonly used system for outdoor positionin/navigation, which cannot be used indoors due to the signal loss. In this study, a decentralized structure for FKF is applied in indoor positioning problem by taking its outdoor navigation performance into consideration. Simulations are performed with distance measurements, which are assumed to be calculated by using Received Signal Strength (RSS). Results gathered via different simulations are evaluated as promising for future studies.
Navigation of Autonomous Mobile Robots in Connected Groups
(IEEE, 2008) Cezayirli, Ahmet; Kerestecioğlu, Feza; Kerestecioğlu, Feza
The navigation of autonomous mobile robots as a group is considered in this paper. Definitions adopted from the graph theory are given to characterize the robot group. A local steering strategy is proposed such that when each robot in the group applies this steering scheme the overall result is that the whole group is displaced without losing its connectivity. This is achieved using only limited-range position sensors and without any communication between the robots.
Nonuniform Sampling for Detection of Abrupt Changes
(Birkhauser Boston Inc, 2003) Kerestecioğlu, Feza; Kerestecioğlu, Feza; Tokat, Sezai
In this work detection of abrupt changes in continuous-time linear stochastic systems and selection of the sampling interval to improve the detection performance are considered. Cost functions are proposed to optimize both uniform and nonuniform sampling intervals for the well-known cumulative sum algorithm. Some iterative techniques are presented to make online optimization computationally feasible. It is shown that considerable improvement in the detection performance can be obtained by using nonuniform sampling intervals.
Zero-Crossing Based Demodulation of Minimum Shift Keying
(2003) Kalkan, Mine; Kerestecioğlu, Feza; Kerestecioğlu, Feza
Minimum shift keying (MSK) modulation has features such as constant envelope compact spectrum and good error performance which are all desirable in many digital applications including mobile radio. Numerous receiver structures to demodulate MSK have been suggested such as correlation receivers differential detectors and frequency discriminators MSK is a form of biphase keying and can be detected by a zero-crossing based phase demodulator which gives near optimum performance. In this paper the bit error performance of a zero-crossing based coherent MSK demodulator is theoretically investigated and a closed-form expression for the bit error rate is derived. The results indicate that the demodulator performs within 0.8-1 dB of the theoratical optimum for MSK. Towards the goal of deriving probability of bit error it is also shown that under additive white Gaussian noise (AWGN) zero-crossing locations of MSK signals are Gaussian distributed except at very low signal-to-noise ratios.
Fault Tolerant Indoor Positioning Based on Federated Kalman Filter
(Springer, 2024) Ayabakan, Tarik; Kerestecioğlu, Feza; Kerestecioglu, Feza
In this article, multi-sensor indoor positioning, which is based on fusing tri-laterated position data of the target, is considered. A novel method, which is based on federated Kalman filtering and makes use of the fingerprint data, namely, federated Kalman filter with skipped covariance updating (FKF-SCU) is proposed. The data collected on two test beds are used in comparing the performances of the proposed algorithm and that of the regular federated filter. It is shown that the proposed algorithm provides fault tolerance and quick recovery, whenever signal reception from an access point is interrupted, as well as an improvement of 12.57% on the position accuracy.
Connected Navigation of Non-Communicating Mobile Agents
(IEEE, 2012) Kerestecioğlu, Feza; Kerestecioğlu, Feza; Cezayirli, Ahmet
This article discusses the connectivity of autonomous mobile robots that do not have communication capabilities. We show that if the group members follow the proposed Local Steering Strategy which utilizes information only about the relative positions of neighbor robots they can sustain their connectivity even in the case of bounded position measurement errors and the occultation of robots by other robots in the group. To reduce the computational burden in the implementation of the proposed methodology we used sub-optimal solutions. © 2012 IEEE.
A Re-Configuring Sliding-Mode Controller With a Ustable Robustness
(Pergamon-Elsevier Science Ltd, 2004) Demirci, Ufuk; Kerestecioğlu, Feza; Kerestecioğlu, Feza
In this paper a controller design method for underwater vehicles is presented which is based on re-configuration of a sliding-mode controller in case of disturbances caused by shallow water conditions. The disturbance distribution information can be obtained and used to update the corrective gain vector of the sliding-mode controller. This increases the robustness of the controller and hence keeps the system performance within acceptable limits. Proposed method is validated with simulations on a submarine model. (C) 2003 Published by Elsevier Ltd.
Design and Implementation of a Nano-Scale High-Speed Multiplier for Signal Processing Applications
(Elsevier, 2024) Ahmadpour, Seyed-Sajad; Kerestecioğlu, Feza; Jafari Navimipour, Nima; Ul Ain, Noor; Kerestecioglu, Feza; Yalcin, Senay; Avval, Danial Bakhshayeshi; Hosseinzadeh, Mehdi
Digital signal processing (DSP) is an engineering field involved with increasing the precision and dependability of digital communications and mathematical processes, including equalization, modulation, demodulation, compression, and decompression, which can be used to produce a signal of the highest caliber. To execute vital tasks in DSP, an essential electronic circuit such as a multiplier plays an important role, continually performing tasks such as the multiplication of two binary numbers. Multiplier is a crucial component utilized to implement a wide range of DSP tasks, including convolution, Fourier transform, discrete wavelet transforms (DWT), filtering and dithering, multimedia information processing, and more. A multiplier device includes a clock and reset buttons for more flexible operational control. Each digital signal processor constitutes a multiplier unit. A multiplier unit functions entirely autonomously from the central processing unit (CPU); consequently, the CPU is burdened with a significantly reduced amount of work. Since DSP algorithms must constantly carry out multiplication tasks, the employment of a high-speed multiplier to execute fast-speed filtering processes is vital. The previous multipliers had lots of weaknesses, such as high energy, low speed, and high area, because they implemented this necessary circuit based on traditional technology such as complementary metal-oxide semiconductor (CMOS) and very large-scale integration (VLSI). To solve all previous drawbacks in this necessary circuit, we can use nanotechnology, which directly affects the performance of the multiplier and can overcome all previous issues. One of the alternative nanotechnologies that can be used for designing digital circuits is quantum dot cellular automata, which is high speed, low area, and low power. Therefore, this manuscript suggests a quantum technology-based multiplier for DSP applications. In addition, some vital circuits, such as half adder, full adder, and ripple carry adder (RCA), are suggested for designing a multiplier. Moreover, a systolic array, accumulator, and multiply and accumulate (MAC) unit are proposed based on the quantum technologybased multiplier. Nonetheless, each of the suggested frameworks has a coplanar configuration without rotated cells. The suggested structure is developed and verified utilizing the QCADesigner 2.0.3 tools. The findings showed that all circuits have no complicated configuration, including a higher number of quantum cells, latency, and an optimum area.