Tayfun GÜNEL, Mustafa Emre AYDEMİR

Uçak antenleri arasındaki kuplajın sürekli parametreli genetik algoritma ile optimizasyonu

Bu çalışmada F-4 Phantom uçağı üzerine yerleştirilmesi planlanan iki UHF-VHF telsizin birbirlerinin antenleri üzerinde meydana gelebilecek girişim etkisinin optimizasyonu hedeflenmiştir. Optimizasyon metodu olarak sürekli parametreli Genetik ve Memetik Algoritmalar kullanılmıştır. Sayısal analizde uçağın tel ızgara modeli oluşturulmuş, Moment Yöntemi tabanlı Super NEC programı ile MATLAB bir arada kullanılarak antenler arasındaki kuplaj hesaplanmış ve optimize edilmiştir. Ölçüm yönteminde ise, 1:10 ölçekli bakırdan imal edilen uçak modeli üzerinde tam yansımasız odada kuplaj ölçümleri yapılmıştır. Farklı yöntemlerle elde edilen sonuçlar karşılaştırılmış, sayısal analiz ve ölçüm sonuçlarının birbirleri ile uyumlu oldukları gözlemlenmiştir.

Optimization of the coupling among the aircraft antennas via the continuous parameter genetic algorithm

High density of electronic equipment, receiver and transmitters used in modern aircraft makes Electromagnetic Interference (EMI) of high priority concern. In such platforms, providing Electromagnetic Compatibility (EMC) among systems is difficult due to the simultaneous operation modes. Antenna mounting on an aircraft needs special attention and experience. The conducting surfaces of these aircraft seriously affect the radiation patterns of the antennas in a manner of re-radiation or cross polarization. In this study, the optimization of the electromagnetic interference induced by two on-board VHF-UHF transreceiver antennas is aimed. The continuous parameter Genetic and Memetic Algorithms are chosen for the optimization method. In the numerical analysis, the wire-grid model of the aircraft is constructed; the Method of Moments (MoM) is utilized for calculating the coupling between the antennas by using SuperNEC. In the measurement process, coupling and S-parameters are measured on a 1:10 scaled model in an anechoic chamber. The originality of this study is that it combines the MoM Computational Electromagnetics (CEM), CPGA and CPMA optimization methods for the minimization of coupling between the F-4 Phantom aircraft antennas. When applied together, it is seen that these methods solve very complex and time-consuming problem efficiently. It can be concluded the selected method is an accurate and low-cost alternative for the expensive and timeconsuming measurement methods and a suitable tool for verifying the validity of the measurement results.

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