Investigation on the EM-Coupled Stacked Square Ring Antennas With Ultra-Thin Spacing

Abstract

Stacked electromagnetically coupled square ring antennas with extremely thin spacing are studied. The separation between rings is kept very small so that they do not increase the overall antenna height, yet can provide multiband operation. The coupling effects among these very closely placed rings are studied based on substrate parameters so that they can be practically implemented using commercially available microwave substrates. It is observed that with an asymmetric arrangement of the stacked rings, different polarizations can be obtained for different resonances. However, if a fixed polarization is desired, a concentric stacked rings configuration has to be used. Experimental investigations are conducted to confirm simulation results.Index Terms-Microstrip antennas, microstrip ring antennas, polarization, stacked microstrip ring antennas.

Multiband monopole antenna with minimised ground plane influence for portable devices

“…Due to this, there is a shifting trend from using traditional narrow band antenna for wireless applications towards utilising a single compact multiband antenna to support multiple wireless standards. Moreover, this overcomes the space limitation in mobile devices, as manufacturers compete to increase compactness and miniaturisation of overall wireless communication system [1][2][3][4].…”

“…Multiband functionality can be achieved by either etching slots on the radiator or the ground plane [1][2][3], stacking of patches [4][5], reactive loading [6][7][8], loop antennas [9,10] and/or the fractal geometries [11][12][13]. The slots introduction reduces the radiation efficiency, whereas stacking patches and reactive loading increase the overall antenna size.…”

A Compact Coplanar Waveguide (Cpw)-Fed Dual-Frequency Antenna With Single-Cell Metamaterial Loading

“…These antennas based on conventional transmission lines (TLs) with single branch of dispersion curve use multi separate resonant paths of different lengths of resonators operated at half or quarter wavelength modes to obtain the dual resonances. Electromagnetically (EM) coupled techniques are available to miniaturize microstrip antennas [12,13]. On the other hand, research into metamaterials based on periodic unit-cell for microwave circuit and antenna application has grown rapidly with the verification of left-handed (LH) metamaterials [14][15][16][17][18][19][20].…”