Çoklu Kırınımlar İçeren Senaryolar için Elektromanyetik Dalga Yayılım Modelleri

Abstract

Dijital yayın sistemlerinde daha güvenilir yayın yapmak için kapsama alanı ve alıcı üzerindeki alan şiddetinin kestiriminde yayılım modelleri kullanılmaktadır. Yayılım modelleri temelde nümerik ve ışın izleme tekniğine dayanan modeller olmak üzere iki ana grupta incelenebilir. Elektromanyetik dalga yayılım modellerinde hesaplama zamanı ve kestirilen alan şiddetinin kesinliği arasında bir ödünleşme vardır. Nümerik modeller kesin sonuçlar vermesine karşın, hesaplama zamanı yüksektir, ışın izleme tekniğine dayanan modeller ise kesinliği az olmakla beraber hesaplama zamanı düşüktür. Hesaplama zamanı ve kesinlik açısından optimum olan modellere ihtiyaç duyulmuştur. Bunun için birçok model geliştirilmiştir

Keywords

• Elektromanyetik Dalga Yayılımı, Eğim Kırınımı, Düzgün Kırınım Teorisi, Çoklu Kırınım

Electromagnetic Wave Propagation Models for Multiple-Diffraction Scenarios

Abstract

Electromagnetic wave propagation models have been used for coverage estimation and field prediction at the receiver to make more reliable and efficient digital broadcasting systems. Propagation models can be classified into two groups as numerical and ray tracing based models. There is a tradeoff between computation time and accuracy of field prediction among electromagnetic wave propagation models. Although numerical models predict accurately, it requires more computation times. Ray tracing based models predicts the field strength less accurately with lower computation time. Many propagation models have been developed to provide optimum solution for accuracy and computation time

Keywords

• Electromagnetic Wave Propagation, Slope Diffraction, Uniform Theory of Diffraction, Multiple-diffraction

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48. Makale 25.06.2012 tarihinde alınmış, 10.07.2013 tarihinde düzeltilmiş, 25.02.2014 tarihinde kabul edilmiştir.