SATILMIŞ TOPCU | Bilkent University (original) (raw)

Papers by SATILMIŞ TOPCU

Ömer Mörgül, the members of my jury, for their motivating and directive comments on my research. ... more Ömer Mörgül, the members of my jury, for their motivating and directive comments on my research. I like to acknowledge the financial support of TÜBİTAK through the Science for Stability Programme for presentation of this work in ISC AS'91. It is my pleasure to express my thanks to Ogan Ocali for his valuable discussions and comments especially about the popcorn algorithm. I would also like to thank Cemal T. Dikmen and Murat Alaybeyi for their collaboration in writing the core of the program, PLAWE. Thanks to Mustafa N. Yazgan for providing the grafix program to view and print the PLAWE outputs. A special note of thanks is due to my friends Mustafa Karaman, F. Levent Değertekin, Dilek Çolak, Ayhan Bozkurt and Mustafa Çelik for their moral support and friendship. Finally, my sincere thanks are due to my family for their continuous moral support throughout my graduate study.

Sayısal karasal TV planlaması

Karasal sayısal yayıncılık teknolojileri ve ülkemizdeki durum

Sayısal televizyon yayıncılığında frekans planlama

International Journal of Electronics, Sep 1, 1997

A method is described to exploit asymptotic waveform evaluation (AWE) in the time-domain analysis... more A method is described to exploit asymptotic waveform evaluation (AWE) in the time-domain analysis of nonlinear circuits by using SPICE models for nonlinear devices such as diodes, transistors, etc. Although AWE has been used for linearized circuits only, the aim is to enhance the accuracy of the simulation while preserving the computational e ciency obtained with AWE and to eliminate the piecewiselinear modelling problem. Practical examples are given to illustrate signi® cant improvements in accuracy. For circuits containing weakly nonlinear devices, it is demonstrated that this method is typically at least one order of magnitude faster than SPICE.

Geniş ölçekli pürüzlü yüzeylerden saçınım ve yayınım problemleri için hızlı yöntemler ve uygulamaları

The use of propagation prediction for broadcast and telecommunication services

Application of fast methods to large scale rough surface scattering and propagation problems

Milli frekans yönetim sistemi

2016 10th European Conference on Antennas and Propagation (EuCAP), 2016

This paper presents a propagation prediction technique to predict propagation mechanisms for fixe... more This paper presents a propagation prediction technique to predict propagation mechanisms for fixed terrestrial line-of-sight (LOS) radio links, especially proposed for rural environments. We report the results of a short-term propagation measurement campaign carried out in the area of Ankara, Turkey. The field measurements were performed at the frequency of 2.536 GHz for a period of three months in summer 2015. It is observed that the difference between measurement data and predicted mean received power is smaller than the standard deviation value provided by Recommendation ITU-R P. 1546. Index Terms-fixed terrestrial line-of-sight (LOS) radio link, field measurement, point-to-point communication, propagation modeling. I.

Sabit karasal noktadan-noktaya haberleşme sistemlerinin analizi

2015 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting, 2015

In this paper, the calculation of both the total received power with the effect of the ground ref... more In this paper, the calculation of both the total received power with the effect of the ground reflection and the fade margin to find out the link availability for terrestrial microwave LOS (line-of-sight) radio links is proposed. The expressions are derived from clear-air, rainfall propagation mechanisms and multipath fading due to multipath arising from surface reflection along the defined microwave LOS radio link. We verify the mathematical model by using the ATDI ICS telecom software over sample microwave LOS radio links located in Turkey.

Evaluating spatial diversity technique for mitigating multipath fading of fixed terrestrial point-to-point systems

2015 23nd Signal Processing and Communications Applications Conference (SIU), 2015

Computer-Aided Frequency Planning for the Radio End TV Broadcasts

International Journal of RF and Microwave Computer-Aided Engineering, 2016

In HF broadcasting, the transmitters are typically very powerful. In the case of Turkish Radio an... more In HF broadcasting, the transmitters are typically very powerful. In the case of Turkish Radio and Television (TRT), total transmission average power may reach up to 5 MW. Therefore, it is natural to utilize solar panels as a means of alternative/backup energy for the continuous transmission of RF signal satisfying the requirement of broadcasting. In the TRT HF broadcasting array field, two areas are designated as the candidate areas for solar panel installation. In these areas, electric fields are simulated, measured, and compared. Simulations are done using the Numerical Electromagnetic Code (4nec2). The suitability of the regions for the solar panel installation are evaluated based on the ICNIRP human exposure limits. In addition, 4nec2 simulations are used to see the effect of metal frames of solar panels on the radiation patterns of the shortwave antenna arrays in the two solar panel candidate areas of TRT HF broadcasting station. Simulation results show that metal frames do not seem to have a significant effect on the radiation patterns of the shortwave antenna arrays.

$Research paper thumbnail of A new approach to diffraction modelling for line-of-sight (LOS) paths$

2015 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC), 2015

In this paper, we present a new knife-edge diffraction method based on Bullington method for the ... more In this paper, we present a new knife-edge diffraction method based on Bullington method for the terrestrial line-ofsight (LOS) paths. The diffraction loss of our new knife-edge diffraction method is compared with the results obtained from the Delta-Bullington method and the measurement data existing in the literature for sample fixed terrestrial microwave line-ofsight (LOS)/ non line-of-sight (NLOS) radio links. The revised Bullington method is shown to perform significantly better than the Delta-Bullington method for both overland and coastal/overwater radio links.

2014 XXXIth URSI General Assembly and Scientific Symposium (URSI GASS), 2014

Multipath fading is an important constraint on the prediction of path loss for terrestrial line-o... more Multipath fading is an important constraint on the prediction of path loss for terrestrial line-of-sight microwave links. The International Telecommunication Union-Radiocommunication (ITU-R) Rec. P.530 [1] is one of the most widely used methods providing guidelines for the design of terrestrial line-of-sight links. The purpose of the study presented in this paper is to make an investigation of the effect of both terrain roughness and geoclimatic factor parameters in the path loss characteristics of microwave line-of-sight (LOS) propagation in NATO Band 3+ (1350-2690 MHz) and NATO Band 4 (4440-5000 MHz) frequency ranges. The two parameters led to significantly different results for the link availability due to multipath fading as a function of the fade margin.

IEEE Transactions on Circuits and Systems I: Fundamental Theory and Applications, 1994

IEEE Transactions on Broadcasting, 1996

The frequency planning of the VHF and UHF broadcasts in Turkey is described. This planning is don... more The frequency planning of the VHF and UHF broadcasts in Turkey is described. This planning is done with the aid of computer databases and digital terrain map. The frequency offset is applied whenever applicable t o increase the channel capacity. The offset assignment is done through Simulated Annealing algorithm. The international rules and regulations concerning Turkey are also considered.