Pandu gelombang empat segi telah digunakan secara meluas di dalam aplikasi gelombang mikro terutamanya satellit, radar dan sistem perhubungan. Apabila frekuensi meningkat kepada gelombang mikro frekuansi, ketepatan permisenan yang tinggi diperlukan untuk fabrikasi sesetengah jenis pandu gelombang empat segi untuk mengurangkan toleransi. Di dalam projek ini, pandu gelombang empat segi dengan dielektrik tirus pada frekuensi 10 GHz telah diperkenalkan dan prototaip itu telah direalisasikan di dalam makmal Universiti Sains Malaysia. Struktur tersebut terdiri daripada pandu gelombang empat segi tirus dan dielektrik tirus. Dimensi dalam pandu gelombang empat segi WR90 ialah 22.86 mm x 10.16 mm. Terdapat tiga jenis dielektrik tirus yang diperkenalkan dalam projek ini. Simulasi reka bentuk menggunakan perisian Ansoft HFSS telah dibentangkan dan prototaip telah dihasilkan menggunakan CNC mesin untuk mengesahkan keputusan simulasi. Satu persediaan pengukuran telah diperkenalkan untuk menilai prestasi reka bentuk menggunakan Network Analyzer. Hasil keputusan simulasi dan uji kaji dibandingkan dan dibincangkan. S11 untuk reka bentuk simulasi adalah -56.36 dB dan S21 adalah -0.05 dB. Hasil uji kaji adalah -10.24 dB dan -1.15 dB.
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Rectangular Waveguide (RGW) were widely used in microwave application especially satellite, radar and communication system. As the frequency increase to the microwave frequency, high precision machining was required to fabricate the certain type of rectangular waveguide in order to reduce tolerances. In this project, a rectangular waveguide with the dielectric taper at the operating frequency of 10 GHz was introduced and the prototype was realized in University Science Malaysia (USM) laboratory. The structure was composed of tapered rectangular waveguide and dielectric taper. The dimension of the inner dimension of standard WR90 waveguide was 22.86 x 10.16 mm. There were three types of the dielectric taper introduced in this project. The simulation of the design using Ansoft HFSS was presented and the prototype was fabricated using CNC milling to verify the simulation results. A measurement setup was introduced to evaluate the performance of design using Network Analyzer. Both simulation and measured results were compared and discussed. The return loss, S11 for simulated design was -56.36 dB and the insertion loss, S21 was -0.05 dB. For the measured results, the return loss was -10.24 dB and the insertion loss was -1.15 dB.
Fabrication of low loss hollow substrate integrated waveguide / Zunurain Muhamad Zukri