A Modified SWB Hexagonal Fractal Spatial Diversity Antenna With High Isolation Using Meander Line Approach

Abstract

This manuscript introduces a novel miniaturized super wideband (SWB) hexagonal fractal spatial diversity 2-element multiple-input-multiple-output (MIMO) antenna for broadband applications, as a compact wideband antenna is required for military radio and space communication devices. The designed antenna includes two hexagonal (1 st modified Koch iteration) Koch fractal radiators with two linear tapered feedlines (TLTF) and a step tapered slotted ground plane (STSGP) that provides the broad impedance characteristic with miniaturized size in the operating band of 1.78-30 GHz. Moreover, the STSGP is also accountable for enabling the isolation (S 12/21 ) better than 10 dB. To further meet the isolation higher than 22 dB, a meander line is protruded from the ground plane while maintaining a 6 mm edge-to-edge distance between two antenna elements. Typically, the MIMO antenna with high isolation is beneficial for highspeed data transmission. The experimental outcomes represent that the proposed MIMO antenna is with the advantages of reasonably good diversity gain (nearly 10 dB), stable radiation patterns, high peak gain (almost 6.6 dBi), and moderate radiation efficiency (around 85%) across -10 dB impedance bandwidth. The total active reflection coefficient (TARC) and envelop correlation coefficient (ECC) are less than -25 dB and 0.1 respectively. Due to all these attributes, the proposed 2-element MIMO antenna array can be a potential candidate for military radio, spectrum sensing for cognitive radio, and space communication applications.

Design and Implementation of a Planar MIMO Antenna for Spectrum-Sensing Applications

“…A two-port SWB MIMO antenna with modified feather-shaped radiators was proposed [35], where a metal strip was added between the resonators to improve correlation among antenna elements. A compact SWB MIMO antenna comprising hexagonal Koch fractal-shaped radiators was presented [36]. In this antenna design, a meander line decoupler was built from the ground plane to improve mutual coupling.…”

Reconfigurable dual element dual band MIMO antenna for 5G (Sub-6 GHz) and WLAN applications

“…Initially, as indicated in Figure 2, a hexagonal radiator (HR) was constructed, which evolved from a circular radiator (CR). The resonance frequency expression (RFE) for a Existing MIMO antenna layouts 5G (Sub-6 GHz) and WLAN applications regular HR can be derived using the RFE of a CR by equating the effective area of a CR to the area of a regular HR and given by the following equation (1) (Chaudhary and Manohar, 2022):…”

“…Initially, as indicated in Figure 2, a hexagonal radiator (HR) was constructed, which evolved from a circular radiator (CR). The resonance frequency expression (RFE) for a regular HR can be derived using the RFE of a CR by equating the effective area of a CR to the area of a regular HR and given by the following equation (1) (Chaudhary and Manohar, 2022): where R is the HR’s side arm length and R eff is the CR’s effective radius. The R eff may be calculated using the radius of a CR, as shown in equation (2): where R 1 is the radius of a CR, T s is the substrate thickness, and ε r is the substrate dielectric constant.…”

SBD Synthesis of Dual-Band Perturbed Minkowski Monopole Fractal Antennas

“…Such a necessity has been driving during the last decade a remarkable interest in the design of innovative multi-band antennas (i ) simultaneously transmitting/receiving electromagnetic (EM ) energy within different portions of the spectrum and (ii ) enabling a miniaturization of the radio-frequency (RF ) front-end [3][4][5][6]. In such a framework, fractal antennas are considered an effective and versatile recipe to implement low-profile radiating structures naturally exhibiting different scales of detail that are independently excited at different wavelengths of the TX/RX signal [7][8][9][10][11][12][13][14]. However, designs based on conventional fractal shapes, whose geometry descriptors are derived by means of iterative analytical relationships, generally exhibit fixed-ratio locations of the working resonances [7,8].…”