Realization and analitical and numerical analysis of a groove type resonator at millimeter waves

Bir yarı-simetrik oyuklu dalga kılavuzu rezonatörü 20 – 40 GHz frekans bandında kullanılmak üzere tasarlanmış ve duraleminyum kullanılarak gerçeklenmiştir. Rezonatör, biri düz diğeri ise dairesel oyuk içeren iki plakadan oluşmuştur. Uygun hareketli bir destek sistemine monte edilen rezonatörün, gerekli ölçüm düzeni de hazırlanarak, frekans spektrumu gözlenmiş, rezonans frekansları ve kalite faktörü ölçülmüştür. Oyuklu rezonatör, hem analitik ve hem de sayısal yöntemler kullanılarak analiz edilmiştir. Kullanılan sayısal yöntem zamanda sonlu farklar (FDTD) yöntemidir. Ölçüm sonucu elde edilen rezonans frekansları, analitik ve sayısal yöntemlerden elde edilenlerle karşılaştırılmıştır. Anahtar Kelimeler: Oyuklu dalga kılavuzu, oyuklu rezonatör, FDTD, mikrodalga, transfer rezonans metodu.As an alternative to the classical waveguides, such as the H-waveguide and the rectangular waveguide, the Groove waveguide has been used at millimeter wavelengths for the last couple of decades. It has many advantages such as low-loss and higher power handling capacity. Here, in this study, a semi-symmetrical groove guide resonator based on groove waveguide structure is designed and fabricated. Instead of using the classical symmetrical shaped groove guide, a novel semi-symmetrical groove guide structure is presented for the first time. This semi-symmetrical structure was chosen because it is easier to fabricate and excite. The groove resonator which has one grooved plate and one plane plate, first analyzed analytically. Since exact solutions usually exist for idealized geometries, the closed resonator structure is taken into account first. The Green's function method is applied for different oriented line sources. Then the transverse resonance method is used for the open groove resonator. The numerical simulations are performed via the powerful time domain simulator FDTD (Finite Difference Time Domain). Both cartesian and cylindrical coordinate systems are used for FDTD calculations. Here, the purpose to use cylindrical coordinate is to calibrate cartesian coordinates for discretization. Then, a measurement setup which includes a movable support platform was established from 20 GHz to 40 GHz. The resonance frequencies and loaded quality factor are measured. Analitical and numerical results are compared with measurements and a good agreement was observed.Keywords: Groove waveguide, groove resonator, FDTD, microwave, transverse resonance method.