New technique to drive the central frequency and to improve bandwidth of EBG structures

Abstract

In this paper, a parametric study was done to find out the superstrat influence on locating the central frequency of the band gap. The present work compares the standard mushroom like with the EBG structures which are located between the substrate and the superstrat. The main motivation is to present a theoretical contribution by comparing the equations describing the central frequency of the band gap. In that way, this work investigates a new proposed design to shift the central frequency of the forbidden band to a low frequency, by inserting meandered lines to connect each part of the unit cell, which give an added capacitance to the EBG structures, in order to reach a low profile and lightweight EBG structure. The band gap was recognized by computing the transmission coefficient S21 resorting to the suspended line method (SLM).

Enhanced Low Profile, Dual-Band Antenna via Novel Electromagnetic Band Gap Structure

“…Many have studied the Sievenpiper structure, which is known as mushroom-like structure [1][2][3][4][5][6][7][8][9][10][11][12][13]. Due to their particular features such as the attenuating mutual coupling and high directivity, EBG structures were found to be very useful when being combined with antennas, and soon practical applications were proposed, such as their use as a ground plane on a curl antenna to obtain circular polarisation and a low profile [2], or their effectiveness on coupling reduction between two patch antennas placed above a EBG mushroom-like structure [3].…”

“…Based on our previous work [11,12], this paper proposes a new EBG design to be combined with a dipole antenna, thus targeting dual-band, low profile, and high performance antenna, while at the same time decreasing SAR levels. The operating frequencies were selected to match operating bands of different mobile communication applications.…”