A stacked annular-ring microstrip patch antenna

Analysis of a Gap-Coupled Stacked Annular Ring Microstrip Antenna

“…It is observed that displacement of feed point from inner periphery of the ring towards outer periphery causes considerable mismatching at lower resonance frequency and moderate mismatching at higher resonance frequency. For the comparative study of theoretical, simulated and Angle (degrees) E-plane, theoretical H-plane, theoretical E-plane, experimental [5] H-plane, experimental [5] Relative radiative power (dB) Figure 9. Radiation pattern of the proposed antenna at frequency 2.23 GHz.…”

“…experimental [5] results, the optimized return loss curves for the proposed antenna are shown in Fig. 6 as a function of frequency.…”

“…Although, in principle, the patch may be of any shape yet, in practice, only simple geometries like rectangular, square and circular structures are commonly employed. Like rectangular and circular patches, the annular ring microstrip antenna (ARMSA) has received the considerable attention of several investigators [1][2][3][4][5][6][7][8] due to its many salient features such as small size and broader bandwidth compared to other conventional patches. However, the main obstacle that restricts its wide applications in various fields is its inherent narrow bandwidth and low gain [1].…”

“…Therefore, a number of bandwidth extension techniques have been suggested to achieve better performance of the ARMSA including use of thick substrate [2], use of air gap [3], use of superstrate [4], use of parasitic elements [5][6][7] and integration of active devices [8]. Among these techniques, the stacked parasitic configuration has been selected because it provides close spacing between the elements that is not realized in single layer parasitic elements, it does not excite surface waves that occur in thick dielectric substrate, and it does not generate high order modes that are generated for low dielectric substrate [7].…”

“…In this paper, the theoretical investigation of a gapcoupled stacked annular ring microstrip antenna is presented in which foam material introduces an air gap between the fed and parasitic patches. The results obtained are compared with simulated (IE3D) and experimental [5] results.…”