Dual-band multiple-element MIMO antenna system for next-generation smartphones

This work presents a cost-effective multiple-element multiple-input multiple-output (MIMO) antenna system for next-generation smartphones. The proposed antenna system is developed on a 0.8 mm thin FR-4 substrate with a relative permittivity of 4.4, which consists of one main board and two sideboards. The dimensions of the main board and the two side boards are 150 × 75 mm2 and 150 × 6 mm2, respectively. The radiating elements are printed on the sideboards to provide space for other radio frequency (RF) components to be embedded on the main board. The proposed antenna resonates at two distinct allotted 5G bands, i.e., 3.5 GHz and 5.4 GHz, with impedance bandwidths of 200 MHz and 700 MHz, respectively. The isolation between the antenna elements is noted to be >18 dB and >12 dB for the 3.5 GHz and 5.4 GHz frequency bands. In addition, the proposed MIMO antenna provides pattern and spatial diversity characteristics in both bands with good gain and efficiency. Furthermore, the MIMO parameters such as envelope correlation coefficient (ECC), mean effective gain (MEG), and channel capacity (CC) are calculated, and it is observed that the MIMO antenna offers good diversity performance for the bands of interest. A prototype is fabricated and measured to verify the numerical data. The simulated results were discovered to be in excellent agreement with the measured results. It is also observed that the proposed MIMO antenna system holds promising features, and can be utilized for future generations of smartphones.Princess Nourah bint Abdulrahman Universit

H-Shaped Eight-Element Dual-Band MIMO Antenna for Sub-6 GHz 5G Smatphone Applications

The design of an eight-element H-shaped dual-band multiple-input multiple-output (MIMO) antenna system for sub-6 GHz fifth-generation (5G) smartphone applications is presented in this work. The radiating elements are designed on the side edge frame of the smartphone, placed on both sides of the main printed circuit board (PCB). Each side edge consists of four radiating elements, which ensures low mutual coupling between antenna elements. The total size of the main PCB is 150×75 mm 2 , while the size of the side edge frame is 150×7 mm 2 . A single antenna consists of an H-shaped radiating element fed using a 50Ω microstrip feeding line designed on the main board of the smartphone. The results show that, according to −6 dB impedance bandwidth criteria, the designed MIMO antenna radiates at two different frequency ranges within the allocated 5G spectrums, i.e., 3.1–3.78 GHz and 5.43–6.21 GHz with 680 MHz and 780 MHz bandwidths, respectively. It is also observed that the antenna elements are able to provide pattern diversity for both the frequency bands. Furthermore, an isolation of >12 dB is observed between any two given radiating elements. Numerous MIMO critical performance characteristics are assessed, including diversity gain (DG), envelope correlation coefficient (ECC), and channel capacity (CC). A prototype is built, measured, and it is observed that the measured and simulated data correspond well. On the basis of performance characteristics, it can be claimed that the suggested MIMO system may be used in 5G communication networks.Dr. Mohammad Alibakhshikenari acknowledges support from the CONEX-Plus programme funded by Universidad Carlos III de Madrid and the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 801538

Eight-Port Modified E-Slot MIMO Antenna Array with Enhanced Isolation for 5G Mobile Phone

An eight-element antenna system operating at sub 6 GHz is presented in this work for a future multiple-input multiple-output (MIMO) system based on a modified E-slot on the ground. The modified E-slot significantly lowers the coupling among the antenna components by suppressing the ground current effect. The design concept is validated by accurately measuring and carefully fabricating an eight-element MIMO antenna. The experimentation yields higher element isolation greater than −21 dB in the 3.5 GHz band and the desired band is achieved at −6 dB impedance bandwidth. The E-shape slot occupies an area of 17.8 mm × 5.6 mm designed on an FR-4 substrate with dimensions of 150 mm × 75 mm × 0.8 mm. We fed the I-antenna element with an L-shape micro-strip feedline, the size of the I-antenna is 20.4 × 5.2 mm2, which operates in the (3.4–3.65 GHz) band. Moreover, our method obtained an envelope correlation coefficient (ECC) of <0.01 and an ergodic channel capacity of 43.50 bps/Hz. The ECC and ergodic channel capacity are important metrics for evaluating MIMO system performance. Results indicate that the proposed antenna system is a good option to be used in 5G mobile phone applications

Eight Element MIMO Antenna Array with Tri-Band Response for Modern Smartphones

This article presents an eight-element tri-band Multiple Input Multiple Output (MIMO) antenna system for future handheld devices. The suggested antenna system consists of a main and sideboards. The feed lines are connected on the main board while the antennas are placed on sideboards, two on each side separately. The total dimension of the main board is 150×75 mm2, and the sideboard is 150×7 mm2. The antenna resonates at three distinct 5G allocated bands of 3.1-3.7 GHz, 4.47-4.91 GHz, and 5.5-6.0 GHz with impedance bandwidths of 600 MHz, 440 MHz, and 450 MHz, respectively. The antenna system provides pattern and spatial diversity characteristics with radiation and total efficiency of 78% and 62% and peak gain of 5.8 dBi. The MIMO system is fabricated, and the measured results are found to be in good agreement with the simulations. The isolation among radiating elements in all resonating bands is found to be >16 dB. The vital MIMO performance parameters such as envelope correlation coefficient (ECC) is less than 0.2 for any two antenna array meeting the required standard of less than 0.5 alongside the mean effective gain or MEG ratio of any two antenna meeting the required standard of less than 3 dB for power balance and optimal diversity. The Channel Capacity (CC) is found to be 41.1 bps/Hz, approximately 3 times that of 2× 2 MIMO operations

Uni-Planar MIMO Antenna for Sub-6 GHz 5G Mobile Phone Applications

This article presents the design of a uni-planar MIMO antenna system for sub-6 GHz 5G-enabled smartphones. The MIMO antenna designed comprises four loop-shaped radiators placed at each corner of the mobile phone board, which follows the principle of pattern diversity. The single-antenna element resonates at 3.5 GHz, its impedance bandwidth is noted to be 1.28 GHz (3-4.28 GHz) for S11 90%. The isolation of >10 dB between antenna elements is achieved for the MIMO configuration. Furthermore, the MIMO antenna designed provides enough radiation coverage to support different sides of the mobile phone board, which is an important feature for future 5G-enabled handsets. In addition, the impacts of human hands and heads on MIMO antenna performance are investigated, and acceptable performance in the data and conversation modes is observed.The authors sincerely appreciate the support from Universidad Carlos III de Madrid and the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant 80153

mmWave polarization diversity wideband multiple-input/multiple-output antenna system with symmetrical geometry for future compact devices

The fifth generation (5G) of mobile networks is a significant technological advancement in telecommunications that provides faster data speeds, lower latency, and greater network capacity. One of the key technologies that enables 5G is multiple-input/multiple-output (MIMO) antenna systems, which allow for the transmission and reception of multiple data streams simultaneously, improving network performance and efficiency. MIMO is essential to meeting the demand for higher data rates and improved network performance in 5G networks. This work presents a four-element MIMO antenna system dedicated to the upper 5G millimeter-wave (mmWave) spectrum. The suggested antenna system is designed using an ultra-thin RO5880 substrate having total dimensions of 20 x 20 x 0.254 mm(3) with symmetrical geometry. The proposed antenna covers a fractional bandwidth of 46.875% (25-38 GHz), covering potential 5G bands of 26, 28, and 32 GHz, and offers isolation of >18 dB. The proposed MIMO system is fabricated and tested in-house. The antenna showed efficiency >88% at the potential band of interest and a peak gain of 3.5 dBi. The orthogonal arrangement of the resonating elements provides polarization diversity. Also, the MIMO parameters obtained, such as mean effective gain (MEG), envelope correlation coefficient (ECC), diversity gain (DG), channel capacity loss (CCL), and total active reflection coefficient (TARC), are found to have good performance. The measured results obtained are found to be in good agreement with simulations, hence making the proposed MIMO antenna suitable for handheld mmWave 5G devices.Prince Sultan University, Riyadh, Saudi Arabi

Donut-Shaped mmWave Printed Antenna Array for 5G Technology

This article presents compact and novel shape ring-slotted antenna array operating at mmwave band on central frequency of 28 GHz. The proposed structure designed at 0.256 mm thin Roggers 5880 is composed of a ring shape patch with a square slot etched at the top mid-section of partial ground plane. Through optimizing the ring and square slot parameters, a high bandwidth of 8 GHz is achieved, ranging from 26 to 32 GHz, with a simulated gain of 3.95 dBi and total efficiency of 96% for a single element. The proposed structure is further transformed in a 4-element linear array manner. With compact dimensions of 20 mm 22 mm for array, the proposed antenna delivers a high simulated gain of 10.7 dBi and is designed in such a way that it exhibits dual beam response over the entire band of interest and simulated results agree with fabricated prototype measurements

Ultra-wideband pentagonal fractal antenna with stable radiation characteristics for microwave imaging applications

For microwave imaging applications, a design for an ultra-wideband (UWB) fractal antenna is presented. The antenna design is composed of a pentagonal fractal patch radiator fed by a modified co-planar waveguide (CPW) ground plane. It is built on a low-loss Rogers RT/Duroid 5880 dielectric substrate with a dimensions of 24 × 30 × 0.787 mm3. According to the measurements, the designed antenna offers a fractional bandwidth of 123.56% ranging from 3 GHz to 12.7 GHz. In addition, a maximum gain of 3.6 dBi is achieved at 8.5 GHz. From the results, it is also observed that the proposed antenna structure attains constant radiation characteristics in the operating bandwidth, which is useful for microwave imaging applications. The time domain analysis of the proposed design is also performed, and it is observed that the designed antenna offers a group delay of ≤1.5 ns, which ensures minimum pulse distortion

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

A Compact mmWave MIMO Antenna for Future Wireless Networks

This article presents a four-element multiple-input multiple-output (MIMO) antenna design for next-generation millimeter-wave (mmWave) communication systems. The single antenna element of the MIMO systems consists of a T-shaped and plow-shaped patch radiator designed on an ultra-thin Rogers RT/Duroid 5880 substrate. The dimensions of the single antenna are 10 × 12 mm2. The MIMO system is designed by placing four elements in a polarization diversity configuration whose overall dimensions are 24 × 24 mm2. From the measured results, it is observed that the MIMO antenna provides 9.23 GHz impedance bandwidth ranging from 22.43 to 31.66 GHz. In addition, without the utilization of any decoupling network, a minimum isolation of 25 dB is achieved between adjacent MIMO elements. Furthermore, the proposed MIMO antenna system is fabricated, and it is noted that the simulated results are in good agreement with the measured results. Through the achieved results, it can be said that the proposed MIMO antenna system can be used in 5G mmWave radio frequency (RF) front-ends