Numerical analysis is presented for the characteristic parameters of centered-inclined coupling slot in rectangular waveguides, taking into account the transverse distribution of the electric field across the slot ape...Numerical analysis is presented for the characteristic parameters of centered-inclined coupling slot in rectangular waveguides, taking into account the transverse distribution of the electric field across the slot aperture. Integral equations are formulated based on dyadic Green's function theories and solved using the method of moments. Trigonometric basis functions are adopted. It is found that the method will converge with up to ten basis functions. The characteristic parameters can be easily obtained for different slot sizes. Resonant length and resonant resistance of the coupling slots are calculated. It is shown that the calculated results have very high accuracy, compared with simulated results obtained from commercial software. Therefore, it can be effectively applied in the synthesis of antenna arrays. Effects of the transverse distribution on calculating resonant parameters of the coupling slot are also analyzed. The results show that if the transverse distribution of the electric field is neglected, the calculated error tends to become larger when the slot gets wider or thinner.展开更多
A rigorous analysis of a broad wall slot coupler composed of two crossed rectangular waveguides by using FDTD method is presented. Two types of slots, a longitudinal/transverse slot and a centered-inclined slot, are a...A rigorous analysis of a broad wall slot coupler composed of two crossed rectangular waveguides by using FDTD method is presented. Two types of slots, a longitudinal/transverse slot and a centered-inclined slot, are analyzed. Coupling slot characteristics are obtained, including scattering parameters and the resonant length for different waveguide dimensions and frequencies. The numerical results are all in good agreement with those by the method of moments. A coupler system with a short circuit port is also analyzed to help designing the slot array.展开更多
Orogeny is always associated with the erosion and sediments carried by both transverse and longitudinal river systems. Those two river systems transport sediments into foreland or hinterland basin and flank basin. Lon...Orogeny is always associated with the erosion and sediments carried by both transverse and longitudinal river systems. Those two river systems transport sediments into foreland or hinterland basin and flank basin. Longitu-dinal river systems prevail in and around the Tibetan Pla-teau due to the fact that they flow parallel to the strike of structures within the developing mountain belt. The flank basins surrounded the Tibetan Plateau and adjacent areas are developed in different tectonic settings, including inland, continental margin and deep ocean, most of them containing oil and natural gas. Those basins not only have longer evolu-tion histories than foreland basins but also are more com-plete in their records of deposition. Coupling of orogeny and flank basin deposition also occurred widely in pre-Cenozoic time, in particular, the coupling between the Qinling oro-genic belt and Songpan-Ganzi flysch flank basin is the most distinctive. The evolution of ancient latitudinal rivers derived from the Qinling orogenic belt during periods of mountain building was controlled not only by landforms but also by the lateral extrusion of the crustal fragments.展开更多
文摘Numerical analysis is presented for the characteristic parameters of centered-inclined coupling slot in rectangular waveguides, taking into account the transverse distribution of the electric field across the slot aperture. Integral equations are formulated based on dyadic Green's function theories and solved using the method of moments. Trigonometric basis functions are adopted. It is found that the method will converge with up to ten basis functions. The characteristic parameters can be easily obtained for different slot sizes. Resonant length and resonant resistance of the coupling slots are calculated. It is shown that the calculated results have very high accuracy, compared with simulated results obtained from commercial software. Therefore, it can be effectively applied in the synthesis of antenna arrays. Effects of the transverse distribution on calculating resonant parameters of the coupling slot are also analyzed. The results show that if the transverse distribution of the electric field is neglected, the calculated error tends to become larger when the slot gets wider or thinner.
文摘A rigorous analysis of a broad wall slot coupler composed of two crossed rectangular waveguides by using FDTD method is presented. Two types of slots, a longitudinal/transverse slot and a centered-inclined slot, are analyzed. Coupling slot characteristics are obtained, including scattering parameters and the resonant length for different waveguide dimensions and frequencies. The numerical results are all in good agreement with those by the method of moments. A coupler system with a short circuit port is also analyzed to help designing the slot array.
文摘Orogeny is always associated with the erosion and sediments carried by both transverse and longitudinal river systems. Those two river systems transport sediments into foreland or hinterland basin and flank basin. Longitu-dinal river systems prevail in and around the Tibetan Pla-teau due to the fact that they flow parallel to the strike of structures within the developing mountain belt. The flank basins surrounded the Tibetan Plateau and adjacent areas are developed in different tectonic settings, including inland, continental margin and deep ocean, most of them containing oil and natural gas. Those basins not only have longer evolu-tion histories than foreland basins but also are more com-plete in their records of deposition. Coupling of orogeny and flank basin deposition also occurred widely in pre-Cenozoic time, in particular, the coupling between the Qinling oro-genic belt and Songpan-Ganzi flysch flank basin is the most distinctive. The evolution of ancient latitudinal rivers derived from the Qinling orogenic belt during periods of mountain building was controlled not only by landforms but also by the lateral extrusion of the crustal fragments.
