Design of Low-Profile Single- and Dual-Band Antennas for IoT Applications

This paper presents novel low-cost single- and dual-band microstrip patch antennas. The proposed antennas are realized on a square microstrip patch etched symmetrically with four slots. The antenna is designed to have low cost and reduced size to use in Internet of things (IoT) applications. The antennas provide a reconfigurable architecture that allows operation in different wireless communication bands. The proposed structure can be adjusted to operate either in single band or in dual-band operation. Two prototypes are implemented and evaluated. The first structure works at a single resonance frequency (f1 = 2.4 GHz); however, the second configuration works at two resonance frequencies (f1 = 2.4 GHz and f2 = 2.8 GHz) within the same size. These antennas use a low-cost FR-4 dielectric substrate. The 2.4 GHz is allotted for the industrial, scientific, and medical (ISM) band, and the 2.8 GHz is allocated to verify the concept and can be adjusted to meet the user’s requirements. The measurement of the fabricated antennas closely matches the simulated results.

Initial designing a dual-band antenna baced on end-fed dipole-like radiators for digital antenna arrays

The paper deals with the designing of the initial arrangement for dual-band antennas comprising two parallel dipole-like radiators as the drivers for the mentioned antenna. The excitation of the drivers is provided by the source of the induced electromotive forces (EMF), whose outputs are attached to the remote terminals of the radiators. The paper also provides the key electrodynamic characteristics of the structure under research for the following procedure of multi-parametric nonlinear optimization. In addition, on the basis of the induced EMF method, has been obtained the expressions for the far-field zone (Fraunhofer zone) characteristics with taking into account the parasitic currents on the radiating bodies of the dipole, which allows more accurate design of the initial topology of the antenna.

A new two-element MIMO antenna system for cognitive radio applications

Purpose This study aims to propose a two-element multi-input-multi-output (MIMO) antenna for cognitive radio MIMO applications to avoid the complexities involved in reconfigurable antennas and improve the spectrum utilization efficiency. Design/methodology/approach The proposed MIMO antenna system comprises a wideband antenna that operates at 2 GHz–12 GHz for sensing the spectrum and four pairs of antennas for communication, which are single and dual-band antennas. Each pair of antennas meant for communication consists of two similar antennas. Moreover, the antennas meant for communication cover 93% of the bandwidth of the sensing antenna. Findings The first pair of antennas accessible at ports P2 and P6 and the second pair of antennas accessible at ports P4 and P8, which are dual-band antennas, operate at 3.05 GHz–3.85 GHz, 5.8 GHz–8 GHz and 2.05 GHz–2.55 GHz, 4.7 GHz–6.1 GHz, respectively. While the third pair of antennas accessible at ports P3 and P7 and the fourth pair of antennas accessible at ports P5 and P9 are single-band antennas and operate at 3.85 GHz–4.7 GHz and 8 GHz–11 GHz, respectively. Minimum isolations of 20 dB and 15 dB are attained between every two similar antennas for communication and between the sensing antenna and the antennas meant for communication, respectively. The correctness of the proposed antenna is verified with a fine match between the results obtained from simulations and measurements. Originality/value The proposed MIMO antenna possesses salient features, such as polarization diversity and performing a maximum of four communication tasks when all the white spaces are detected.

Dual-Band Half Psi Shaped Antenna for WLAN, Wi-Fi and WiMAX Applications

In the last few decades, the evolution in new-fashioned wireless communication systems has actuated augmented exploration on uncomplicated dual band antennas. In this paper, a dual-band half psi shaped antenna for WLAN, Wi-Fi and WiMAX appliances is designed and analyzed. The intended antenna constitutes a half psi shaped radiating patch on the cost effective FR4-substrate with 1.6 mm thickness. A 50 ohms feed line is employed to feed half psi shaped antenna. Here a preferable impedance matching is attained by truncating a portion of the ground surface. The intended antenna has the potential to resonate between the frequency bands of 1.88 GHz-2.75 GHz and 5.17 GHz-5.74 GHz with S11 below -10 dB. The design of the antenna and its behavior over various frequencies ranges is done with the use of HFSS. The proposed antenna has higher gains at two regions. The simulated antenna is also prototyped and a fine similarity is attained in between the simulated parameters and measured parameters.