No abstract

No abstract

Abstract-A new technique for designing the substrate integrated waveguide (SIW) frequency-agile slot antenna is presented in this paper. Similar to the metallic waveguide counterpart, the SIW is a uniconductor guided-wave structure and inherently difficult in the electronically tunable applications. To solve this problem, a single slot etched on the top conductor layer of a conventional antenna is instead of two slots to construct an isolated area, which is convenient for the DC bias. The electric length of slots can then be adjusted through two shunt varactors welded near the center of slot. As such, a SIW frequency-agile slot antenna is realized and fabricated to cover the frequency of 2.30 ∼ 2.74 GHz with different bias voltages. Experiments verify our theory analysis and design process. Then, a frequency-agile multibeam antenna is developed to cover several frequency bands while switching between four different radiation patterns pointing at different spatial locations for each frequency. It presents an excellent candidate for software and cognitive radio system applications.

Abstract-A high-performance multilayer dual-mode filter is developed based on the substrate integrated waveguide circular cavity (SICC) in this paper. The filter is constructed with two circular cavities and each cavity supports two degeneration modes, which can be generated and controlled by the coupling aperture and slot located between layers. Detailed design process is introduced to synthesize an X-band dual-mode dual-layer filter. It not only has the good performances, but also reduces the circuit size much more. Moreover, it can be found that the upper side response of the filter is very steep. Good agreement is obtained between the simulated and measured results of the proposed structure.

Abstract-A multilayer dual-mode complementary filter is developed based on substrate integrated circular and elliptic cavity (SICC and SIEC) in this paper. The filter is constructed with two different kinds of cavities, and each cavity supports two degenerate modes, which can be generated and controlled by the coupling aperture and slot located between layers. Detailed design process is introduced to synthesize an X-band dual-mode complementary filter. It not only has good performance, but also reduces the circuit size much more. Moreover, Sharp transition characteristic both in the lower and upper sidebands demonstrates high selectivity of the filter. Good agreement is obtained between the simulated and measured results of the proposed structure.