UWB MIMO Research Articles

Flexible Thin Film-Based Triple Port UWB MIMO Antenna With Modified Ground Plane for UWB, WLAN, WiMAX, WPAN and 5G Applications

Flexible Thin Film-Based Triple Port UWB MIMO Antenna With Modified Ground Plane for UWB, WLAN, WiMAX, WPAN and 5G Applications

Resistance Loaded UWB MIMO with Enhanced Isolation for S and C Band Applications

Resistance Loaded UWB MIMO with Enhanced Isolation for S and C Band Applications

Mutual Coupling Reduction in UWB MIMO Antenna Using T-shaped Stub

Mutual Coupling Reduction in UWB MIMO Antenna Using T-shaped Stub

On demand reconfigurable notch-based UWB MIMO antenna for wireless application

In this paper, on demand reconfigurable notch based UWB-MIMO antenna for wireless applications has been proposed. The proposed antenna consists of two square patch monopole radiators with inverted Z and extended U slots cut through them. Antenna offers good impedance matching (S11 < -10 dB) over the entire Ultra-Wide Band (2.9–13.4 GHz) spectrum. The connected ground structure is used to improve the isolation (S21 < -15 dB) over the entire operating band. Reconfigurability has been achieved using switching elements S1 and S2 which are inserted in the extended U slot and inverted Z slot in each radiator. When both the switches are OFF, notch mechanism is obtained on both the notches C band uplink (5.7 to 6.5 GHz) and C band downlink (3.6 to 4.2 GHz) simultaneously. When the Switch 1 is ON the notch is obtained at C band uplink (5.7 to 6.5 GHz) whereas when the Switch 2 is ON the notch is obtained at C band downlink (3.6 to 4.2 GHz). The proposed antenna offers a simulated bandwidth of 10.5 GHz along with a compact size of 34 × 20 × 1.6 mm 3 with efficient port isolation of more than −15 dB throughout the operating band. ECC and directive gain are less than 0.02 and more than 9.9 dBi respectively.

Four-port UWB MIMO Vivaldi Antenna Based on Resistor and Radiant Patch Loading

Four-port UWB MIMO Vivaldi Antenna Based on Resistor and Radiant Patch Loading

A High Isolation UWB MIMO Vivaldi Antenna Based on CSRR-NL for Contemporary 5G Millimeter-Wave Applications

A High Isolation UWB MIMO Vivaldi Antenna Based on CSRR-NL for Contemporary 5G Millimeter-Wave Applications

Design of Compact Planar Monopole UWB MIMO Antenna with Four Orthogonal Elements and Tapered Fed Configuration for Wireless Diversity Applications

In this paper, we introduce a four-port self-isolated UWB MIMO antenna for diversity applications. First, we have developed a basic radiating element of the proposed antenna in four stages of design, where patches of geometrically different shapes were added at each stage to arrive at the final radiator form. The antenna was designed on an FR-4 substrate with a compact size of 28 × 28 × 1.6 mm3. A tapered microstrip feeding was employed to enhance the antenna’s impedance matching. An orthogonal arrangement of the four radiators was adopted to mitigate the mutual coupling between them, avoiding the use of a separate isolation structure. A prototype was built and measured with a close agreement between the experimental and simulated results. The MIMO antenna performed well in the entire frequency spectrum of 3.1–10.6 GHz, with an isolation better than 20 dB. The measured envelope correlation coefficient (ECC) was less than 0.001, the diversity gain (DG) was greater than 0.99 dB, and the total active reflection coefficient (TARC) was less than −10 dB. The performance of the proposed antenna design was compared with existing designs. The comparison showed that the proposed quad-element UWB MIMO array is compact, has good isolation and diversity performance compared to existing designs, and is well-suited for wireless diversity applications.

Characteristic Mode Analysis-Based Compact Dual Band-Notched UWB MIMO Antenna Loaded with Neutralization Line.

The advancement of electronic gadgets makes it possible for a device to be multipurpose, which calls for attributes such as compactness and larger bandwidth, with improved data transfer rate. This paper introduces the compact, closely placed two-port dual band-notched UWB antenna using a neutralization line as a decoupling structure. The projected antenna design comprised a circle and rectangle embedded monopole radiator with the defected ground structure to attain the UWB spectrum. Further dual notches are attained by carving the U-shape and inverted U-shape slots on the feedline and radiator. The dual band-notched UWB antennas are placed with the separation of 3.8 mm (0.04 λ; λ is computed using 3.4 GHz frequency). The coupling effect between the close proximity elements is decoupled using the neutralization line. The presented antenna has overall dimensions of 21.5 × 28 × 1.6 mm3 (0.24 × 0.31 × 0.01 λ3) and exhibits S11 below −10 dB from 3.4–11.9 GHz, with isolation better than 16 dB throughout the impedance bandwidth. The antenna also provides frequency band rejection of 4.5–5.3 GHz and 7.2–9 GHz covering the WLAN and entire X-band satellite communication. The projected antenna is explored through characteristic mode analysis, time-domain characteristics, and MIMO diversity features to analyze the effectiveness and usefulness of the antenna. The group delay is less than 1 ns except for the frequency rejection band and fidelity factor greater than 0.96. The projected antenna exhibits MIMO diversity metrics ECC < 0.3, DG > 9.6 dB, MEG < −3 dB, TARC < −10 dB, CCL < 0.3 bps/Hz, and ME < −2 dB across the operational frequency, except for the notched bands. The designed two-port antenna is validated by printing on an FR4 substrate. The simulated and measured findings are in line with and appropriate for MIMO wireless applications.

An epsilon-shaped fractal antenna for UWB MIMO applications

An epsilon-shaped fractal antenna for UWB MIMO applications

Isolation Enhancement of UWB MIMO rDRA for 5G Outdoor Applications

In this paper, a two-port Ultra-Wideband Multiple Inputs Multiple Outputs (UWB MIMO) rectangular Dielectric Resonator Antenna (rDRA) is proposed for 5G sub-6 GHz outdoor applications. An edged hole is inserted at the rDRA edge for isolation enhancement purposes. The effect of edged hole radius on isolation is investigated. Both UWB MIMO rDRA with and without edged holes are investigated for both parallel and orthogonal feed schemes (four scenarios). Isolation better than -22 dB is obtained for orthogonal orientation and edged hole rDRA. Surface current density distribution is used to explain that isolation enhancement. UWB bandwidth and high efficiency are obtained on the operating bands due to the usage of an aperture-coupled feed system and edged hole rDRA. The proposed antenna has two -6 dB operating frequency bands, the lower band (2.25 GHz – 2.52 GHz) and the higher band (3.6 GHz – 5.7 GHz). The Envelope Correlation Coefficient (ECC) and diversity gain DG are used to justify the MIMO antenna performance. Good agreement is obtained between measured and simulated results.

Analysis of integrated UWB MIMO and CR antenna system using transmission line model with functional verification

This paper discusses the equivalent circuit model and functional verification of an integrated antenna system as its main focus. The integrated antenna system consists of two independent antenna systems, namely the Cognitive Radio antenna and the Ultra Wide Band Multiple Iinput Multiple Output antenna. This article is split into two parts: The first part discusses the equivalent circuit of an integrated antenna system by optimizing the RLC values. The developed lumped equivalent circuit model produces the NB resonant frequencies, which is the same as the S-parameter obtained through EM simulation. The second part of this paper aims to discuss the experimental verification of an integrated CR antenna system with Bayesian learning-based spectrum sensing algorithms using Universal Software Radio Peripheral devices. Real-time sensing and communication functionalities are visualized in the LABVIEW monitor. The integrated antenna system is fabricated and measured after the simulation.

A compact antenna design for UWB MIMO applications

A compact UWB-MIMO antenna design with an impedance bandwith from 3.2 GHz to 9.1 GHz is presented. The MIMO antenna has a transmission coefficient response less than -14 dB at the resonance frequency bandwidth. To improve the isolation and the antenna performance, an Electromagnetic Band Gap (EBG) structure is introduced between elements, that consists of an added microstrip at ground plane, a 9x1 periodic metal-square patches on top of the substrate, and vertical vias connecting the patches to the ground plane. The EBG structure design methodology is presented. The isolation enhancement between elements is 4 dB at frequency bandwidth. The compact UWB-MIMO antenna with EBG structure reaches a maximum isolation of -33 dB at 6.42 GHz. The peak gain is 4.8 dBi at 7.3 GHz in the H-plane radiation, and 3.3 dBi at 7.3 GHz in the E-plane radiation.

UWB MIMO antenna with 4-element, compact size, high isolation and single band rejection for high-speed wireless networks

In this paper, a miniaturized size UWB 4-element MIMO antenna with a band rejection feature is introduced. The four elements have a rectangular radiator with curved edges and a partial ground plane with an etched slot to enlarge the bandwidth of the suggested structure to operate from 3 up to 12 GHz with S11 ≤ − 10 dB. The high isolation between elements was achieved by forming the antennas orthogonally without adding decoupling elements to simplify the design. The suggested design has a size of 47 × 47 mm2 placed on low price FR4 substrate. A simple slot is etched into the radiator to achieve the desired band rejection. The simulated and tested outcomes achieved operated band extended from 3 up to 12 GHz with band rejection feature within 3.3 GHz up to 4.3 GHz to eliminate interference with WIMAX applications and high isolation of more than 22 dB between ports. Also, the antenna fulfills peak gain of 3.5 dBi, envelope correlation coefficient(ECC) < 0.005, diversity gain (DG) 9.98 dB and channel capacity loss (CCL) < 0.4 bit/s/Hz within the operating bands. The outcomes have good consistency which made the suggested antenna to be used in UWB MIMO systems.

Compact fractal based UWB mimo antenna with dual band dispensation

Compact fractal based UWB mimo antenna with dual band dispensation

Compact Wearable UWB MIMO Antenna with Reduced Mutual Coupling and Notch Characteristics of WLAN Band

Compact Wearable UWB MIMO Antenna with Reduced Mutual Coupling and Notch Characteristics of WLAN Band

Novel MIMO Antenna System for Ultra Wideband Applications

The design of a 4 × 4 MIMO antenna for UWB communication systems is presented in this study. The single antenna element is comprised of a fractal circular ring structure backed by a modified partial ground plane having dimensions of 30 × 30 mm2. The single antenna element has a wide impedance bandwidth of 9.33 GHz and operates from 2.67 GHz to 12 GHz. Furthermore, the gain of a single antenna element increases as the frequency increases, with a peak realized gain and antenna efficiency of 5 dBi and &gt;75%, respectively. For MIMO applications, a 4 × 4 array is designed and analyzed. The antenna elements are positioned in a plus-shaped configuration to provide pattern as well as polarization diversity. It is worth mentioning that good isolation characteristics are achieved without the utilization of any isolation enhancement network. The proposed MIMO antenna was fabricated and tested, and the results show that it provides UWB response from 2.77 GHz to over 12 GHz. The isolation between the antenna elements is more than 15 dB. Based on performance attributes, it can be said that the proposed design is suitable for UWB MIMO applications.

Compact CPW fed Four Port MIMO Antenna for UWB applications with Wi-Fi/ISM/WLAN Band Notch Characteristics

A compact UWB with WLAN notch-based four-element CPW fed MIMO/diversity antenna is presented in this paper. Multiple elements facilitate the design to transmit and receive the signal from all directions enhancing the channel capacity and diversity performance. The inverted L-shaped stub attached to the ground enhances the impedance bandwidth (10 dB) and provides the UWB response. Plus and cross-shaped decoupling structure is accomplished to diminish the surface current and enhances the isolation between antenna elements and it is more than 20.2 dB from port-1 to port-4 without affecting the impedance bandwidth and radiation pattern. A complimentary split ring resonator (CSRR) in the radiator is utilized to eliminate the Wi-Fi/WLAN band. The |S11| of UWB MIMO antenna varies from 3.26 GHz to 14 GHz which can be utilized in portable, Radar, Satellite, and wireless applications. The simple decoupling structure is used to correlate and isolate the antenna elements, therefore acceptable ECC and CCL parameters are achieved.

Compact high isolation UWB MIMO antennas

In this work, two elements (with two versions) compat UWB MIMO antennas are designed and fabaricted. CST software is used in the simulation process. The two elements MIMO antenna have a size of 29.5 × 60 mm2. Measured S parameters show that the MIMO antennas work well from 3 GHz up to 20 GHz (representing the maximum working frequency of the measurent instrumnts). Mesurement results show that the isolation between the antenna elemnts is higher than 23 dB for the first version of the two elements UWB MIMO antenna. In addition, mesurement results show that the isolation between the antenna elemnts is higher than 30 dB for the second version of the two elements UWB MIMO antenna. Measurements show a channel capacity loss lower than 0.4 bps/Hz and a low group delay variation.

4-port UWB MIMO antenna with bluetooth-LTE-WiMax band-rejection and vias-MCP loaded reflector with improved performance

In this article, a 4-port MIMO antenna of dimension 0.46λ0 × 0.46λ0 × 0.01λ0 (λ0 is the lowest operating wavelength at 2.08 GHz) is proposed. It consists of array of fractal radiators sorted orthogonally with 0.05λ0 edge-to-edge separation and contorted feeds perform as impedance transformer. A centered π-shaped inverted-L notch asserts rejection at bluetooth-LTE-WiMax band. The MIMO configuration has common ground plane with no decoupling topology provides an inter-elemental port isolation > 15 dB. There are four vias-Metallic conducting probes (vias-MCP) connected to antenna ground and reflector. The conducting probes enroute the near-field currents from radiators and neutralize into the loaded reflector, with isolation improved > 20 dB and antenna performances are enhanced. The reflector has dimension 0.58λ0 × 0.58λ0 fixed at Hair = 0.07λ0 (≈ 10 mm). The antenna operates from (2.08–10.4) GHz with band rejection at (2.27–3.62) GHz, asserts improved gain characteristics (7–9.57) dBi at pass band and −4 dBi at notched band. This new technique of vias-MCP in the proposed multi-port configuration mitigates mutual interaction of surface wave coupling on radiators, reduces near-field condensed currents and couplate the surface waves into the loaded reflector to improvise impedance matching and gain characteristics for UWB wireless communication systems.

Design and SAR Analysis of Wearable UWB MIMO Antenna with Enhanced Isolation Using a Parasitic Structure

Design and SAR Analysis of Wearable UWB MIMO Antenna with Enhanced Isolation Using a Parasitic Structure