Design of SIW cavity models to control the bandwidth of frequency selective surface

Abstract

This study describes substrate integrated waveguide (SIW) cavity models to control the bandwidth of frequency selective surfaces (FSSs). Two different SIW cavities were presented: one model to reduce (cavity‐I) and another model to improve (cavity‐II) bandwidth of FSS, respectively. The periodic structures were made of SIW cavies and an FSS slot on either side of the dielectric substrate at the centre of the cavity. To prove the concept, a well‐known cross‐slot FSS element has been studied in two different cases and compared their performance. The conformal behaviour of the unit cells has been estimated by considering the practical requirements. The addressed SIW cavities will improve the electromagnetic (EM) performance of conventional FSS without altering its basic shape. The high Q‐factor of SIW cavity greatly improves the performance of FSS. A full‐wave simulation is used to analyse the response of FSS. The cavity‐I shows 12.61% lesser bandwidth and cavity‐II shows 25.0% higher bandwidth compared to its conventional shape in planar form and 9.1, 26.17% in the conformal form at a bent radius of 50 mm. Besides, performance parameters were studied to evaluate the structural dependency on EM performance. Finally, two designed cavity models are fabricated and proved their performance experimentally.

Design and analysis of dual‐band FSS based on equivalent circuit

“…The simplest single‐band resonant circuit 14,15 is LC series or LC parallel, and its resonant frequency can be expressed by . Combined the design idea of series and parallel, 16 this paper proposes dual‐band equivalent circuit model, as shown in Figure 1.…”

Wide‐angle band‐pass FSS with high‐frequency selectivity based on SIW cavity technology

“…Therefore, SIW technology has been extensively applied in the design of FSSs to realize high-frequency selectivity, rapid cut-off frequency, and so forth. 2,[15][16][17][18][19] However, SIW cavities are usually larger than half a wavelength, and the interaction between working modes of the cavity and FSS resonant modes often results in incident angle instability and narrow bandwidth. 2,[20][21][22][23][24] In Wang and Cheng, 20 the proposed size of SIW cavity is 0.5λ 0 , its incident angle stability can only reach up to 15°and bandwidth is only 7%.…”

“…The SIW has a variety of natural advantages, including high Q value, minimal insertion loss, low profile, and simplicity of integration into planar circuit systems. Therefore, SIW technology has been extensively applied in the design of FSSs to realize high‐frequency selectivity, rapid cut‐off frequency, and so forth 2,15–19 . However, SIW cavities are usually larger than half a wavelength, and the interaction between working modes of the cavity and FSS resonant modes often results in incident angle instability and narrow bandwidth 2,20–24 .…”

A multi-functional frequency selective polarization converter based on substrate integrated waveguide cavities

“…In the recent years, SIW technology has attracted lot of intention for the design of microwave and millimeter wave devices since it allows straight forward integration with microstrip technology [17][18][19][20][21][22]. The SIW resonant cavity has been introduced the improve the performance of the FSS due to its high quality factor [23][24][25][26]. The FSS based on substrate integrated waveguide cavities (SIWC) offers a low-loss and low-cost solution to manipulate the amplitude, phase and polarization of EM waves.…”