Ultra-compact reconfigurable band reject uwb MIMO antenna with four radiators

A compact reconfigurable UWB MIMO antenna with four radiators that accomplish on-demand band rejection from 4.9 to 6.3 GHz is presented. An LC stub is connected to the ground plane by activating the PIN diode for each radiator. Two radiators are placed perpendicular to each other to exploit the polarization diversity on a compact 25 × 50 mm 2 FR4 laminate. Two additional radiators are then fixed obliquely on the same laminate (without increasing size) in angular configuration at ±45° perpendicular to the first two planar radiators still exploiting polarization diversity. The design is validated by prototyping and comparing the results with the simulated ones. On demand band rejection through the use of PIN diodes, wide impedance matching (2–12 GHz), high isolation amongst the radiators, compactness achieved by angular placement of the radiators, low gain variation over the entire bandwidth, band rejection control achieved by adjusting the gap between stub and ground plane, and low TARC values makes the proposed design very suitable for commercial handheld devices (i.e., Huawei E5785 and Netgear 815S housings). The proposed configuration of the UWB MIMO radiators has been investigated first time as per authors’ knowledge. ©2020 keywords: band rejected; envelope correlation co-efficient; four element MIMO; polarization diversity; ultra-wideband multiple input multiple outputEU H2020 Marie Skłodowska-Curie Individual Fellowship ViSionRF (grant no. 840854)COMSATS Research Grant Program (project no. 16-63/CGRP/CUI/ISB/18/847

mmWave Four-Element MIMO Antenna for Future 5G Systems

This paper presents an S-shape four-port Multiple Input Multiple Output (MIMO) wideband mmWave antenna with bandwidth of 25 GHz to 39 GHz. The antenna is designed on 0.254 mm ultra-thin RO5880 with permittivity of 2.3. The dimensions of proposed S-shape antenna are 10 12 mm for single element and 24 24 mm for four-port MIMO configuration. A decoupling network is introduced to further compress mutual coupling among MIMO elements. The peak gain achieved is 7.1 dBi and MIMO assembly delivers diversity scheme. The proposed MIMO antenna is fabricated, and simulated results are found to be in excellent agreement with simulations. Through the results obtained, the proposed MIMO antenna system can be considered as a potential candidate for future mmWave devices.This project has received funding from Universidad Carlos III de Madrid and the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant 801538

A Four Element mm-Wave MIMO Antenna System with Wide-Band and High Isolation Characteristics for 5G Applications

In this article, we propose a light weight, low profile Multiple Input Multiple Output (MIMO) antenna system for compact 5th Generation (5G) mmwave devices. Using a RO5880 substrate that is incredibly thin, the suggested antenna is made up of circular rings stacked vertically and horizontally on top of one another. The single element antenna board has dimensions of 12 × 12 × 0.254 mm3 while the size of the radiating element is 6 × 2 × 0.254 mm3 (0.56λ0 × 0.19λ0 × 0.02λ0). The proposed antenna showed dual band characteristics. The first resonance showed a bandwidth of 10 GHz with a starting frequency of 23 GHz to an ending frequency point of 33 GHz followed by a second resonance bandwidth of 3.25 GHz ranging from 37.75 to 41 GHz, respectively. The proposed antenna is transformed into a four element Linear array system with size of 48 × 12 × 0.254 mm3 (4.48λ0 × 1.12λ0 × 0.02λ0). The isolation levels at both resonance bands were noted to be >20 dB which shows high levels of isolation among radiating elements. The MIMO parameters such as Envelope Correlation Co-efficient (ECC), Mean Effective Gain (MEG) and Diversity Gain (DG) were derived and were found to be in satisfactory limits. The proposed MIMO system model is fabricated and through validation and testing of the prototype, the results were found to be in good agreement with simulations

Design and Performance Study of a Dual-Element Multiband Printed Monopole Antenna Array for MIMO Terminals

This letter presents a study on linearly polarized compact multiband multiple-input-multiple-output (MIMO) antenna system for small mobile terminals. The MIMO antenna system consists of two symmetric printed monopole antennas with edge-to-edge separation of 0.097 λ 0 at 900 MHz. Each antenna element has a capacitive feed and is composed of two twisted lines, a parasitic loop, and a shorting trip that generate five resonant modes around 900, 1800, 2100, 3500, and 5400 MHz, covering GSM850/900, DCS, PCS, UMTS, WLAN, and WiMAX frequency bands. Two inverted-L shaped branches and a rectangular slot with one circular end, etched on the ground plane, were introduced to improve the isolation between antenna elements. The isolation achieved is higher than 15 dB in the lower band and 20 dB in the upper bands, leading to an envelope correlation coefficient of less than 0.025. The simulated performance of the designed antenna system has been verified in the experiment

Eight-Element Compact UWB-MIMO/Diversity Antenna with WLAN Band Rejection for 3G/4G/5G Communications

An eight element, compact Ultra Wideband-Multiple Input Multiple Output (UWB-MIMO) antenna capable of providing high data rates for future Fifth Generation (5G) terminal equipments along with the provision of necessary bandwidth for Third Generation (3G) and Fourth Generation (4G) communications that accomplishes band rejection from 4.85 to 6.35 GHz by deploying a Inductor Capacitor (LC) stub on the ground plane is presented. The incorporated stub also provides flexibility to reject any selected band as well as bandwidth control. The orthogonal placement of the printed monopoles permits polarization diversity and provides high isolation. In the proposed eight element UWB-MIMO/diversity antenna, monopole pair 3-4 are 180o mirrored transform of monopole pair 1-2 which lie on the opposite corners of a planar 50 x 50 mm2 substrate. Four additional monopoles are then placed perpendicularly to the same board leading to a total size of 50 x 50 x 25 mm3 only. The simulated results are validated by comparing the measurements of a fabricated prototype. It was concluded that the design meets the target specifications over the entire bandwidth of 2 to 12 GHz with a reflection coefficient better than -10 dB (except the rejected band), isolation more than 17 dB, low envelope correlation, low gain variation, stable radiation pattern, and strong rejection of the signals in the Wireless Local Area Network (WLAN) band. Overall, compact and reduced complexity of the proposed eight element architecture, strengthens its practical viability for the diversity applications in future 5G terminal equipments amongst other MIMO antennas designs present in the literature.Comment: 25 page

Bandwidth Enhanced MIMO antenna for LTE bands using Split Ring Resonators and Stubs

In this work, an array of circular patch antenna loaded with a partial split ring and a pair of stubs each with same dimensions, on each of the antenna. Patch of the radius (r) = 7.5mm. The split ring is of the width 1.35mm. the split ring not only accounts for a newer operating band, but also tend to reduce the isolation and the stubs are tends to increase the bandwidth which results in change by 44.92% compared to array of antennas without split rings. The substrate dimensions are 55´30´0.8mm3 and the ground of 55´9mm2. The proposed antennas are simulated using high frequency structural simulator and the results compared with the circular patch antenna without split ring resonators. The results obtained clearly show that, bandwidth of circular micro strip antenna without split ring can be enhanced. The proposed antennas may find applications in LTE band 1, 2, 3, 4, 7, 9, 10, 11, 15, 16, 21, 22, 23, 24, 25, 30, 33, 34, 35, 37, 38, 39, 40, 41, 42, 43 GHz covering a broadband width of 2500MHz

CSRR Loaded 2x1 Triangular MIMO Antenna for LTE Band Operation

A 2´1 (two-element) multiple-input multiple-output (MIMO) patch antenna system is designed and fabricated for (2.43 – 2.57) GHz LTE band 7 operation. It uses comple-mentary split -ring resonator (CSRR) loading on its ground plane for antenna miniaturization. This reduces the single-element antenna size by 76%. The total board size of the proposed MIMO antenna system, including the GND plane is 50´50´0.8mm3, while the single-patch antenna element has a size of 18.5 ´16mm2. The antenna is fabricated and tested. Measured results are in good agreement with simulations. A minimum measured isolation of 10 dB is obtained given the close interelement spacing of 0.17λ

Diversity performance of multiantenna systems for UMTS cellular phones in different propagation environments

We present the evaluation of the diversity performance of several two-antenna systems for UMTS terminals. First, a two-antenna system with poor antenna-to-antenna isolation is described. Then, with the help of a neutralization technique, we introduced an optimized structure with high antenna-to-antenna isolation. The key parameters for an efficient diversity performance are then discussed, some of them being actually dependent on the propagation environment (uniform, indoor, outdoor, and outdoor-toindoor chosen here). All these parameters, the total efficiency, the envelope correlation coefficient, the mean effective gain, the diversity gain, and the effective diversity gain, are computed with the help of the simulated radiation patterns of both antenna systems. Next, these key parameters are measured in a reverberation chamber to validate the simulations we achieved in the uniform environment. The comparison of the performance of the two prototypes is especially showing the usefulness of using a neutralization technique for enhanced diversity antenna systems

Design synthesis and miniaturization of multiband and reconfigurable microstrip antenna for future wireless applications

Tese de Doutoramento. Engenharia Electrónica e de Computadores - Telecomunicações. Faculdade de Engenharia. Universidade do Porto. 201