Abstract
This work investigates a high-isolation Orthogonal Printed Elliptical Slot Antenna (OPESA) array with Multiple Inputs and Multiple Outputs (MIMO). A unique composite Electromagnetic Band-Gap (EBG) structure consisting of a vertical six rings positioned between single element antennas were devised and investigated with the aim of reducing mutual interaction between antenna components. A distinct feeble electric field that could successfully inhibit the Mutual Coupling (MC) among the antenna components is easily produced by the suggested composite EBG construction. One type of decoupling constructions throughout the antenna growth was carefully examined at together the theoretical and physical levels in order to offer a clear representation of the suggested antenna array’s design concept and decoupling technique. The antenna array design process was cleverly separated into three stages. In order to verify the suggested decoupling idea, the array Scheme was constructed, assessed, and measured. Studying the antenna gain, radiation pattern, and reflection coefficient, it was found that the simulated and measured findings were very consistent. According to the models, the array has an extreme radiation efficiency of about 91%, a minor value of Envelope Correlation Coefficient (ECC < 1.8 × 10−4), and a maximal gain of 11.5 dBi. The electrical size, highest isolating grade and the recommended MIMO antenna’s 90 dB isolating bandwidth (BW) were assessed. The planned antenna has several appealing features that set it apart from previous similar designs. These features include a low design complexity, a great Diversity Gain rate (DG > 9.99 dB), the BW of the proposed antenna extends from 25 GHz to more than 40 GHz, an enormously great isolation level (about 90 dB), and compressed dimensions (51 mm × 30 × 1.6 mm). For verifying the recommended antenna for MIMO. the suggested MIMO antenna design’s radiation efficiency, a thorough time-domain study is suggested.
Article highlights
-
The suggested 2-port MIMO antenna spans dual tone frequencies, 28 GHz and 38 GHz, and is considered for broad band operation.
-
By combining two single antenna components with orthogonal forms, MC is improved. This configuration’s EBG method, which is positioned between the antenna parts, allows for great isolation, particularly at 38 GHz, getting − 90.5 dB.
-
To verify the radiation effectiveness of the suggested antenna scheme for 5G millimeter-wave signal propagation, a thorough time-domain study is also carried out, resulting in a 95% efficiency.
Similar content being viewed by others
Avoid common mistakes on your manuscript.
1 Introduction
The globe is approaching the fifth generation (5G) era due to the wireless communication industry’s fast expansion [1]. With this backdrop, wireless communication has to meet unprecedented demands for data rate, capacity, and latency. The MIMO antenna has proven to be an essential component of 5G communication systems due to its benefits in terms of increased Improvements in capacity, reduced delays, durability against fading caused by multiple paths, and better data rate [2]. Nonetheless, a progressive reduction in the spacing between antenna components is caused by 5G terminals or platforms that have significant space constraints.
Quality of the antenna, counting impedance BW, radiation shape, and efficiency, might worsen once the antenna component arrangement is smaller than half wavelength in distance, as per the antenna array theory, which states that the MC amid antenna components cannot be minimal [3,4,5]. As a result, MC among antenna parts has always been a problem when designing small MIMO antennas, particularly when space is limited.
In recent decades, a number of efficient decoupling strategies have been planned to reduce the MC between antenna parts [6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44]. These approaches may be broadly categorized into three groups based on the decoupling mechanism [11]. The first kind involves directly reducing the current or wave connection across antenna parts in order to destroy the coupling channel. A common example is the Defected Ground Structure (DGS) [12,13,14,15], which has a band-reject response and can effectually stop surface wave spread by causing disturbances to the current spreading on the antenna ground. However, the main disadvantage of the DGS is that its Front-to-Back Ratio (FBR) is usually high. Thankfully, because of their distinct electromagnetic properties at particular frequencies, different meta-structures have been developed, such as Single Negative metamaterial (SNG) [16, 17], Antenna Decoupling Surface (ADS) [18, 19], Frequency Selective Surface (FSS) [20, 21], Polarization Conversion Surface (PCS) [22], meta-surface construction [23, 24], and EBG building [25,26,27,28], which offer new insights into repressing the connection current or wave between components of antenna. To lessen the coupling, the suggested meta-surface structure was used in between MIMO antenna elements in [20].
The meta-surface structure is thought to function as a spatial band stop filter, therefore suppressing the elements’ spatial electromagnetic movement. The meta-surface isolation wall’s expensive cost and limited BW, however, are drawbacks. In order to address the MC problem in large-scale antenna array organizations, a unique antenna decoupling surface was created in [22] that counteracts coupling waves by producing out-of-phase reflected waves. However, the antenna profile was much enlarged since the decoupled areas of the antenna were positioned around half a wavelength over the antenna’s surface.
A micro-base-station antenna with a polarization of 1 × 2 was constructed in [24] using a meta-surface isolation wall as its foundation. The unique isolation obstacle made of two meta-surfaces connected to the ground plane was employed to lessen interface between micro-base-station arrays. But in order to achieve the same isolation, the meta-surface structure comes at a far greater cost than a standard copper patch. A unique fence-type decoupling building was illustrated in [27], mostly consisting of many slots of identical size.
By acting as a band-stop filter, the many slits efficiently reduced the coupling current among two ports. Though, the manufacturing process is complex and the inserted decoupling assembly impacts the impedance matching at small frequency.
The second category of decoupling approach operates by canceling the initial connection route between elements and adding a new coupling track through the use of a Neutralization Line (NL) [29,30,31,32], or Decoupling Network (DN) [33,34,35], Parasitic Element (PE) [36,37,38,39].
Antenna elements are directly linked to both NLs and DNs, which are made up of lumped components and microstrip circuits. These elements can supply the decoupling current with an identical amplitude and reverse phase to offset the link current. But both NLs and DNs contribute extra insertion loss and make it harder to match impedance in antenna circuits as the interconnector, which reduces antenna efficiency [35]. The parasitic element, which is positioned close to antenna elements without a physical connection, can offer an alternative to the aforementioned strategy for creating an indirect coupling channel.
In order to offset the connection current, an induced current with the same amplitude and reverse phase arises in the parasitic element when the antenna is stimulated. Nevertheless, the initial radiation shape of the antenna is distorted by the field emitted by the generated current in the parasitic element [38]. The majority of decoupling structures that have been documented up to this point usually need additional distance among antenna components or straight up over the surface of the antenna, thus invariably adds to the complexity of the scheme and antenna profile.
Furthermore, the insertion effect is always present when decoupling structures are used, which lowers the antennas’ overall performance, including pattern, radiation efficiency, and impedance match.
Consequently, a third type of decoupling style, in which the MIMO antenna shows excellent natural isolating following design, as the decoupling basis —has been utilized to address the aforementioned drawbacks of depending on decoupling structures [40,41,42,43,44,45,46,47,48,49].
Based on this idea, typical representative decoupling techniques comprise, form diversity [40, 41], polarization multiplicity [42, 43], self-decoupling [44, 45] and the scheme of distinguishing approaches [46]. These techniques have the unique benefit of leaving the antenna act essentially unaffected because no added construction is placed in or around the radiating assemblies. Nonetheless, there are strict restrictions on antenna configurations, feeding techniques, and layout due to polarization or pattern variety. The self-decoupling approach lacks adaptability and an organized design guideline, despite being more inventive and flexible than polarization or shape variety. This is because the self-decoupling effect is typically achieved by utilizing an antenna’s inherent property.
To lessen MC, parasitic components using polarization variety were utilized in [43]. Broadband antennas are not suited for the polarization diversity’s decoupling effect, though. A weak field-based method of self-decoupling was put out in [45]. The neighboring element must be positioned in the region of the feeble field created by the two fields—the radiating patch and the feeding structure—that cancel each other out in order for the mechanism to function. However, this method of decoupling is limited to inset fed patch antenna arrays.
This work proposes and develops a two-element Orthogonal Printed Elliptical Slot Antenna (OPESA) array with good isolation. A further analysis of the EBG structure’s operation reveals that the isolated branch and six rings on the vertical sheet of the building are used to prevent MC among the antenna components. The isolated branch is incorporated into the antenna substrate, whereas the vertical EBG sheet is situated in the center line of the antenna top layer.
The rest of this essay is arranged as follows: The single element Scheme I’s design details are given in Sect. 2. Section 3 presents the single element Scheme II’s design details. In Sect. 4, we talk about the MIMO antenna, covering antenna arrangement, strategy processes, the decoupling idea, and theoretical study of the simulation findings. In Sect. 5, the impact of a few critical decoupling structure factors on antenna performance is examined. Time domain analysis is introduced and described in Sect. 4. Section 5 provides a thorough comparison with earlier, comparable research as well as a commentary. Finally, Sect. 6 presents a succinct conclusion.
2 Designed millimeter wave broadband antenna scheme I
The basic shape of the broadband Printed Elliptical Slot Antenna (PESA) is seen in Fig. 1. Every aspect of the antenna design parameter is displayed in both the top and bottom views. The Scheme antenna has a dielectric constant of \({\epsilon }_{r}\) = 4.3 and is built on a 15 × 15 mm2 (Wx × Wy) FR4 with a thickness of 1.6 mm. An elliptically designed slit carved off the ground plane of center (P2) (representing a Ground Plane Aperture (GPA)) is positioned non-concentrically inside an elliptically molded radiating patch of center (P1). A 50-ohm close proximity-feed microstrip line, positioned on the substrate’s opposite side as seen in Fig. 2, is used to excite the patch. Defected Microstrip structure (DMS) in the form of an inverted L is imprinted in the feed line to enhance impedance matching, as demonstrated in Fig. 3a.
As seen in Fig. 3b–d, the antenna is parametrically studied for key design parameters (R1x, L1, and W6). Table 1 provides an overview of the optimal antenna design parameters based on these parametric research and optimization.
The full-wave electromagnetic simulator CST is utilized to estimate and optimize the performance of the suggested antenna. Using a 50 ohm port impedance. As shown in Fig. 4, the results indicate that the simulated return loss BW (|S11| < −10 dB) spans 22.5 GHz to 34 GHz, covering the 28 GHz bands. The proposed antenna Scheme I’s simulated radiation shapes at a frequency of 28 GHz are displayed in Fig. 5. As it can be seen in the image, the antenna exhibits omni-directional forms with a maximum observed gain of 6.30 dBi.
3 Proposed millimeter wave broadband antenna scheme II
This portion presents the design of the Orthogonal Printed Elliptical Slot Antenna (OPESA) for operating at 28/38 GHz. The knowledge behindhand the recommended antenna is to increase gain and broaden the BW by using two components from Scheme I (PESA) with a 100 ohm proximity-feed microstrip line that is 90° angled toward one another. As seen in Fig. 6, the suggested OPESA is printed on the same side of a FR4 substrate with a 4.3 dielectric constant and a 0.025 loss tangent. Figure 7a illustrates how the OPESA is stimulated using a 50 ohm proximity-feed microstrip line. The top and bottom views are displayed, together with a detailed explanation of the geometric design factors. Table 2 provides the optimum design parameters.
Scheme II and planned Scheme I are compared in Fig. 8. The simulated return loss BW (|S11| < −10 dB) for Scheme I can be shown in Fig. 8a as ranging from less than 25 GHz to 34 GHz, covering the frequency bands (28 GHz), but also from less than 25 GHz to greater than 40 GHz, covering the bands of 28/38 GHz. The simulated gain is displayed in Fig. 8b. Scheme I has a maximum gain of 6.5dBi, whereas Scheme II has a maximum gain of 9.5dBi.
The simulated efficiency is displayed in Fig. 8c. Scheme I has a maximum efficiency of 87.9%, whereas Scheme II has a maximum efficiency of 91.5%. It is observed that the Scheme II covers the dual tone frequencies of 28 and 38 GHz and improves gain and efficiency. Table 3 presents a summary of the antenna Scheme I and Scheme II data, including the estimated radiation efficiency, gain, and BW. It was observed that Scheme II outperforms Scheme I.
The LC resonant circuit is a reasonable approximation for a narrowband antenna. Broadband antennas consist of a cascade of LC resonators, whose overlapping resonant frequencies form the whole wideband resonances of the UWB antenna. The equivalent circuit of the ultra-wideband antenna is drawn using the Advanced Design System (ADS) software. Figure 7b displays the lumped element of the circuit. Figure 7c displays the equivalent circuit of proposed antenna.
As seen in Fig. 7d, the ideal simulation and the similar circuit’s simulation results are contrasted. The Lo and Co components for the transmission line of the suggested antenna in the analogous circuit design are found using Eqs. (1–2) [50]. The inductance and capacitance for the lumped circuit components are computed using Eqs. (3–4). Using ADS software, the antenna equivalent circuit is drawn once the component values have been combined and adjusted. The obtained findings for the total resonant frequencies are shown in the figure to be in good agreement between the CST and ADS software. The circuit achieves the following final results for the component circuit: Lo = 0.192 nH, Co = 0.093 pF, R1 = 57.96 Ω, L1 = 1.686 nH, C1 = 1.94 pF, R2 = 63.67 Ω, L2 = 0.919 nH, C2 = 0.87 pF, R3 = 45.94 Ω, L3 = 0.186 nH, C3 = 1.49 pF, R4 = 61.19 Ω, L4 = 0.151 nH, C4 = 0.83 pF.
where \({W}_{f}\), \(h\), \({\epsilon }_{r}\) is the feed width, substrate thickness, and dielectric constant, respectively.
The antenna is constructed, and Fig. 9a–b display a shot of the finished antenna structures. Figure 10a displays the reflection coefficient |S11| curves that were measured and simulated. The observed results demonstrate high agreement among the simulated and measured results, and the measured return loss BW (|S11| < −10 dB) spans from less than 25 GHz to more than 40 GHz, indicating millimeter wave operations with dual-band at 28/38 GHz. Figure 10b–c display the efficiency and gain. The antenna’s maximum efficiency and gain are determined to be 91.5% and 9.5 dBi, respectively.
The 3D and 2D radiation characteristics for frequencies of 28 and 38 GHz, respectively, are displayed in Figs. 11 and 12. The E Plane and H Plane radiation outlines, both measured and simulated, are displayed. The antenna displays the usual radiation characteristics of a monopole. It can be seen from according to the simulated results, the recommended antenna emits radiation in all directions. There is good agreement between the simulated and observed radiation forms. Figure 1313 demonstrates the corresponding current distribution of the proposed antenna without and with defected ground plane. It visualized that the currents are densely populated and flowing in different directions and this makes coupling between the two antennas causing limited bandwidth as shown in Fig. 13a–b. However, as shown in Fig. 13c–d, using the defected ground plane, the current flows through the transmission feed line and less currents is flowing between the two antennas as it isolates the coupling between them.
4 MIMO antenna arrangement and mutual coupling
The construction of a 2-port MIMO antenna and the way to increase element separation are the main topics of this section. We offer a method of MC reduction with an EBG structure. The dimensions of the suggested design for the array that composed of two-port MIMO are 51 × 30 × 1.6 mm.
As seen in Fig. 14a–b, duplicates of the one antenna unit (Scheme II) from the preceding sector are placed 5 mm apart and perpendicularly to each other. The FR4 substrate is used to build the suggested antenna array. A CST 2019 model of the antenna array is used. Without the use of isolation measures, Fig. 15 illustrates the MC between the ports in a dual-port MIMO array. It is evident that the target band’s isolation is insufficient.
4.1 Isolation enhancement using the EBG structure
One of the main objectives of 5G millimeter-wave applications is to increase MIMO characteristics, and the EBG structure is proposed to improve these properties. As seen in Fig. 16, the vertical EBG sheet in the MIMO antenna arrangement is made up of six rings that are integrated on the top side. The proposed MIMO structure has the following dimensions: 51 × 30 × 1.6 mm.
In order to design the suggested EBG, first, a Ring-shaped EBG unit cell is designed as displayed in Fig. 16c. The dimensions of the proposed EBG unit cell EBG structures of certain dimensions (\(\text{r}\)= 0.4 mm, \(\text{D}\)= 1.2 mm, \(\text{W}\)= 1.3 mm, and \(\text{g}\)= 0.05 mm). A standard 1.6 mm thickness FR4 material (ε = 4.3) is chosen as the substrate. The suggested EBG unit cell is analyzed by utilizing the CST. Figure 16d, presents the S- parameter (phase in degrees) of the Ring unit cell. It is shown that the phase shift between \(\pm {90}^{0}\) involving two resonance frequency 28 GHz and 38 GHz. Figure 16e shows the characteristics, such as permeability, refractive index, and effective permittivity. From Fig. 4, the permittivity is smaller than unity at the frequency band 20–40 GHz. Consequently, printing the array of unit cells, the antenna’s gain can be enhanced.
The MIMO antenna array is manufactured by the photolithographic process, as shown in Fig. 17, after being simulated using the commercial CST 2019. Figure 1818 shows the computed and observed characteristics of the suggested MIMO antenna structure.
As seen in Fig. 18a, the MIMO antenna construction functions as a millimeter-wave 5G antenna, spanning the spectrum from less than 25 to more than 40 GHz. Due to surface waves and space, there is a greater MC between the antennas because of their close proximity. EBG structures of certain dimensions (\(r\)= 0.4 mm, \(D\)= 1.2 mm, \({K}_{3}\)= 1.87 mm, and \({K}_{4}\)= 4.93 mm) are added in order to lessen this.
By efficiently capturing the waves and transforming them into surface currents, these components lessen MC. The isolation between the antennas is seen to vary over the working spectrum, from − 40 dB to − 91 dB, as Fig. 18b illustrates.
As seen in Fig. 18c, d, respectively, the system’s efficiency is around 95% and its gain fluctuates between 8.5 and 11.5 dBi along the operational band. As seen in Fig. 18e, f, the values of DG and ECC are around 10 and less than 1.8 × 10−4, respectively. Figure 18g shows that during the whole band region, the MIMO ‘s total active reflection coefficient (TARC) is less than − 30 dB. Figure 18h displays the CCL (channel capacity loss) of the proposed MIMO array with the EBG insertion.
The planned range of 0.3 bits/s/Hz is reached by the CCL. The little discrepancy among the simulated and measured values might be the result of a soldered connection. But the variance is still within the allowed variety. Figure 19 displays the surface current disseminations. Before adding EBG the current of antenna1 affected on antenna 2. After the EBG is installed, the current is engrossed around the structure of the EBG, causing the remaining antenna parts to sustain less damage and reducing MC.
The radiation pattern in the E- and H-plane at 28 GHz and 38 GHz frequencies is displayed in Fig. 20. As seen in Fig. 20, the major lobes are oriented at phi = 90 degrees and are perpendicular to each other at 28 GHz and 38 GHz, correspondingly. The patterns of the E-plane are 90 degrees out of phase. On the other hand, all antennas exhibit the same E-plane patterns. This demonstrates the ability of the recommended antenna to offer form variety, guaranteeing reception free from interference.
4.2 MIMO antenna performance evaluation
A number of factors are used to assess the MIMO antenna’s effectiveness, and the Envelope Correlation Coefficient (ECC) is one of the most important measures. One important dynamic feature used to measure MIMO antenna system performance is ECC. ECC may be determined using Eq. (5) depending on the S-parameters.
In which the reflection coefficients at Ports 1 and 2 are signified by S11 and S22, individually. The Isolation and Insertion inefficiencies can be expressed by S12 and S21, accordingly.
Where the reflection coefficients at Ports 1 and 2 are denoted by S11 and S22, respectively. The Isolation and Insertion losses are represented by S12 and S21, respectively. The results of ECC using the PE approach are roughly less than \({1.8\times 10}^{-4}\), as shown in Fig. 18f. The transmission power loss in the MIMO scheme while utilizing a diversity mechanism is measured using a metric called Diversity Gain (DG). The following equation from reference [5] can be used to calculate DG:
Figure 18e indicates that DG is around 10 dB.
An additional metric that evaluates the coupling between ports and confirms a MIMO antenna’s functionality is TARC (Total Active Reflection Coefficient). The square root of the total reflected power divided by the square root of the entire incident power is known as TARC. TARC may be computed using Eq. (7) as follows:
θ marks the phase angle of input. which ranges from 0 to 180 degrees with a step increment of 30 degrees. Ports 1 and 2’s reflection coefficients are denoted by S11 and S22, individually. The TARC values are shown in Fig. 18g.
The fourth performance measure, channel capacity loss (CCL), is a vital indicator to assess MIMO systems. The Eq. (8) that follows is used to compute it:
where \({{\Psi }}^{\text{R}}\), which may be expressed as follows, is the receiving antenna’s correlation matrix:
where,
To achieve the needed criterion, as shown in Fig. 18h, CCL must be less than 0.4 bits/s/Hz. Because our plan is less than this amount, it meets CCL.
4.3 Evaluation of the antenna achievement in time domain
The antenna’s time-domain presentation is studied in detail, including Group Delay (GD), S21 phase, and forward transmission coefficient (S21). The simulated time-domain conformation is shown in Fig. 21 in three different configurations: side-to-side, face-to-side, and face-to-face. Two identical antennas are situated 36 mm apart in each of these setups. In these configurations, one antenna functions as the transmitter (Tx) and the other as the receiver (Rx).
The GD, S21 phases, and S21 magnitudes are displayed in Fig. 22. Figure 22a makes it evident that the antenna configurations facing each other and side by side have S21 values below − 40 dB at 28/38 GHz, whereas the configuration facing each other has an S21 value over − 50 dB at 28 GHz and reaching − 60 dB at 38 GHz.
In Fig. 22b, the S21 phase is also displayed to help understand the linearity characteristics within the intended band procedure. It is obvious from the phase curves that the antenna behaves linearly in the desired frequency range in a variety of orientations. Figure 22c presents the GD results to support this observation. At 28 GHz and 38 GHz, the GD is around 0.24 ns and 0.15 ns, respectively.
5 Evaluation in light of related works
Although wideband-frequency band MIMO antennas with excellent isolation have been produced, it is difficult to give up compact dimensions due to design factors including low profile and enhanced gain. This research presents the introduction of a 5G Millimeter-Wave wide-band MIMO antenna array. The 5G Millimeter-Wave wireless terminal is intended for use with the suggested structure. Regarding its small size, number of ports, frequency range, MC methods, MC, gain, efficiency, ECC, and DG, the suggested MIMO antenna array stands out for its exceptional qualities and performance. When compared to related work, its performance is better. Table 4 displays a comparative evaluation of the MIMO antenna topologies that were given, highlighting their respective competitive advantages.
6 Conclusion
We have presented a two-port MIMO array in our work that stands out for having high port isolation. In order to reduce MC between the antennas, we used the EBG technology, which we have carefully assessed for efficacy. We ran simulations with CST version 2019 to maximize the radiating components’ size. The proposed MIMO antenna achieved remarkable isolation values of – 90 dB throughout the whole spectrum, notably at 38 GHz. It was specially intended to work at double tone frequencies, 28/38 GHz.
The proposed MIMO antenna achieved remarkable isolation values of – 90 dB throughout the whole spectrum, notably at 38 GHz. It was specifically planned to work at two resonance frequencies, 28/38 GHz. Because more capacitance was added to the circuit, the EBG approach was essential in improving the isolation between antennas. As a result, it demonstrated strong DG, a high efficiency rating of 91%, and a top gain of 11.5 dBi, demonstrating the technique’s effectiveness.
To fully assess our antenna design’s performance in terms of diversity and highlight the exceptional quality of the suggested two-port MIMO antenna, we took a number of MIMO parameters out of the measurement and simulation data, such as ECC, DG, and CCL. Positive trends were regularly observed in the findings of these investigations inside the two working frequency ranges. This infers that our suggested antenna construction has potential for use in millimeter-wave applications for 5G.
Data availability
Data is contained within the article.
References
Nizar S, Anouar B, Islem BH, Lassaad L. Millimeter-wave dual‐band MIMO antennas for 5G wireless applications. J Infrared Millim Terahertz Waves. 2023;44:297–312. https://doi.org/10.1007/s10762-023-00914-5.
Singh HV, Siva Prasad DV, Tripathi S. Wideband MIMO antenna isolation enhancement using 4th-order cross-coupled decoupling circuit. IEEE Can J Electr Comput Eng. 2022;45:114–23.
Lin J-F, Deng H, Zhu L. Design of Low-Profile Compact MIMO Antenna on a single radiating Patch using simple and systematic characteristic modes Method. IEEE Trans Antennas Propag. 2022;70:1612–22.
Ibrahim AA, Ali WAE, Alathbah M, Sabek AR. Four-port 38 GHz MIMO antenna with high gain and isolation for 5GWireless networks. Sensors. 2023;23:3557–76. https://doi.org/10.3390/s23073557.
Elabd RH, Al-Gburi AJA. Super-compact 28/38 GHz 4-port MIMO antenna using metamaterial-inspired EBG structure with SAR analysis for 5G cellular devices. J Infrared Milli Terahz Waves. 2023. https://doi.org/10.1007/s10762-023-00959-6.
Esmail BAF, Koziel. Design and optimization of metamaterial-based dual-band 28/38 GHz 5G MIMO antenna with modified ground for isolation and bandwidth improvement. IEEE Antennas Wirel Propag Lett. 2023;22(5):1069–73. https://doi.org/10.1109/LAWP.2022.3232622.
Soumik D, Sukomal D, Shiban KK. Isolation improvement of MIMO antenna using novel EBG and hair-pin shaped DGS at 5G millimeter wave band. IEEE Access. 2021;9:162820–34. https://doi.org/10.1109/ACCESS.2021.3133324.
Irtiza AA, Musa H et al. Single patch fractal-shaped antenna with small footprint area and high radiation properties for wide operation over 5G Region, In: 2021 46th international conference on infrared, millimeter and terahertz waves (IRMMW-THz). IEEE, 2021. pp. 1–2, 2021. https://doi.org/10.1109/IRMMW-THz50926.2021.9567165.
Hussain M, United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM). Ultra-Wideband MIMO Antenna Realization for Indoor Ka-band Applications, In: 2022. IEEE, pp. 108–109, 2022. https://doi.org/10.23919/USNC-URSINRSM57467.2022.9881413.
Hussain M, et al. Metamaterials and their application in the performance enhancement of reconfigurable antennas: a review. Micromachines. 2023;14:349. https://doi.org/10.3390/mi14020349.
Nadeem I, Choi D. Study on mutual coupling reduction technique for MIMO antennas. IEEE Access. 2019;7:563–86.
Sufian MA, Askari NH, Park SG, Shin KS, Kim N. Isolation enhancement of a metasurface-based MIMO antenna using slots and shorting pins. IEEE Access. 2021;9:73533–43.
Gao D, Cao Z-X, Fu S-D, Quan X, Chen P. A novel slot-array defected ground structure for decoupling microstrip antenna array. IEEE Trans Antennas Propag. 2020;68:7027–38.
Kowalewski J, Atuegwu J, Mayer J, Mahler T, Zwick T. A low-profile pattern reconfigurable antenna system for automotive MIMO applications. Prog Electromagn Res. 2018;161:41–55.
Liu K, Liu N-W, Fu G. Isolation Improvement of Dual-polarized Microstrip Array Antenna by Using DGS Scheme, In Proceedings of the 2021 IEEE 4th International Conference on Electronic Information and Communication Technology (ICEICT), Xi’an, China, 18–20 August 2021; pp. 514–516.
Bait-Suwailam MM, Boybay MS, Ramahi OM. Electromagnetic coupling reduction in high-profile monopole antennas using single-negative magnetic metamaterials for MIMO applications. IEEE Trans Antennas Propag. 2010;58:2894–902.
Yang F, Peng L, Liao X, Mo K, Jiang X, Li S. Coupling reduction for a wideband circularly polarized conformal array antenna with a single-negative structure. IEEE Antennas Wirel Propag Lett. 2019;18:991–5.
Niu Z, Zhang H, Chen Q, Zhong T. Isolation enhancement in closely coupled dual-band MIMO patch antennas. IEEE Antennas Wirel Propag Lett. 2019;18:1686–90.
Wei C, Zhang Z, Wu K. Phase compensation for decoupling of large-scale staggered dual-polarized dipole array antennas. IEEE Trans Antennas Propag Mag. 2020;68:2822–31.
Yin B, Zhao S, Wang P, Feng X. Isolation improvement of compact microbase station antenna based on metasurface spatial filtering. IEEE Trans Electromagn Compat. 2021;63:57–65.
Huang H. A decoupling method for antennas with different frequencies in 5G massive MIMO application. IEEE Access. 2020;8:140273–8.
Farahani M, Pourahmadazar J, Akbari M, Nedil M, Sebak AR, Denidni TA. Mutual coupling reduction in millimeter-wave MIMO antenna array using a metamaterial polarization-rotator wall. IEEE Antennas Wirel Propag Lett. 2017;16:2324–7.
Hasan M, Islam MT, Samsuzzaman M, Baharuddin MH, Soliman MS, Alzamil A, Abu Sulayman IIM, Islam S. Gain and isolation enhancement of a wideband MIMO antenna using metasurface for 5G sub-6 GHz communication systems. Sci Rep. 2022;12:9433.
Yin B, Feng X, Gu J. A metasurface wall for isolation enhancement: minimizing mutual coupling between MIMO antenna elements. IEEE Antennas Propag. 2020;62:14–22.
Tan X, Wang W, Wu Y, Liu Y, Kishk AA. Enhancing isolation in dual-band meander-line multiple antenna by employing split EBG structure. IEEE Trans Antennas Propag. 2019;67:2769–74.
Bayarzaya B, Hussain N, Awan WA, Sufian MA, Abbas A, Choi D, Lee J, Kim N. A compact MIMO antenna with improved isolation for ISM, sub-6 GHz, and WLAN application. Micromachines. 2022;13:1355–2123.
Wang L, Du Z, Yang H, Ma R, Zhao Y, Cui X, Xi X. Compact UWB MIMO antenna with high isolation using fence- type decoupling structure. IEEE Antennas Wirel Propag Lett. 2019;18:1641–5.
Yang Z, Xiao J, Ye Q. Enhancing MIMO antenna isolation characteristic by manipulating the propagation of Surface Wave. IEEE Access. 2020;8:115572–81.
Sun L, Li Y, Zhang Z. Wideband decoupling of integrated slot antenna pairs for 5G smartphones. IEEE Trans Antennas Propag. 2021;69:2386–91.
Li M, Jiang L, Yeung KL. A general and systematic method to design neutralization lines for isolation enhancement in MIMO antenna arrays. IEEE Trans Veh Technol. 2020;69:6242–53.
Elabd RH, Abdullah HH. A high isolation, UWB MIMO Vivaldi antenna based on CSRR-NL for contemporary 5G millimeter-wave applications. J Infrared Milli Terahz Waves. 2022;43:920–41. https://doi.org/10.1007/s10762-022-00894-y.
Elabd RH, Abdullah HH, Abdelazim M. Compact highly directive MIMO vivaldi antenna for 5G millimeter-wave base station. J Infrared Milli Terahz Waves. 2021;42:173–94. https://doi.org/10.1007/s10762-020-00765-4.
Su S-W, Lee C-T, Hsiao Y-W. Compact two-inverted-F-antenna system with highly integrated π/pi-shaped decoupling structure. IEEE Trans Antennas Propag. 2019;67:6182–6.
Khan A, Bashir S, Ghafoor S, Qureshi KK. Mutual coupling reduction using ground stub and EBG in a compact wideband MIMO-antenna. IEEE Access. 2021;9:40972–9.
Cheng Y, Cheng KM. Compact wideband decoupling and matching network design for dual-antenna array. IEEE Antennas Wirel Propag Lett. 2020;19:791–5.
Zhao L, Wu K. A decoupling technique for four-element symmetric arrays with reactively loaded dummy elements. IEEE Trans Antennas Propag. 2014;62:4416–21.
Xu Z, Zhang Q, Guo L. A compact 5G decoupling MIMO antenna based on split ring resonators. Int J Antennas Propag. 2019;2019:1–10.
Cheng Y-F, Liu J, Wei C, Wu W-J, Sun L, Wang G. Interplanted patch-monopole array with enhanced isolation. IEEE Antennas Wirel Propag Lett. 2022;21:1664–8.
Tran HH, Nguyen-Trong N. Performance enhancement of MIMO patch antenna using parasitic elements. IEEE Access. 2021;9:30011–6.
Ding CF, Zhang XY, Xue C, Sim C. Novel pattern-diversity-based decoupling method and its application to multielement MIMO antenna. IEEE Trans Antennas Propag. 2018;66:4976–85.
Zhao X, Yeo SP, Ong LC, Planar. UWB MIMO antenna with pattern diversity and isolation improvement for mobile platform based on the theory of characteristic modes. IEEE Trans Antennas Propag. 2018;66:420–5.
Hu Y, Pan YM, Yang M. Circularly polarized MIMO dielectric resonator antenna with reduced mutual coupling. IEEE Trans Antennas Propag. 2021;69:3811–20.
Sharma A, Kalaskar KP, Gangane JR, Research C. Analysis of MIMO antennas with parasitic elements for wireless applications, In Proceedings of the (ICCIC), Chennai, India, 15–17 December 2016, pp. 1–4.
Ahmad A, Dy C, Ullah SA. Compact two elements MIMO antenna for 5G communication. Sci Rep. 2022;12:3608.
Lin H, Chen Q, Ji Y, Yang X, Wang J, Ge L. Weak-field-based self-decoupling Patch antennas. IEEE Trans Antennas Propag. 2020;68:4208–17.
Zhang D, Chen Y, Yang S. A self-decoupling method for antenna arrays using high-order characteristic modes. IEEE Trans Antennas Propag. 2022;70:2760–9.
Yang W, Chen L, Pan S, Che W, Xue Q. Novel decoupling method based on coupling energy cancellation and its application in 5G dual-polarized high-isolation antenna array. IEEE Trans Antennas Propag. 2022;70:2686–97.
Abbas A, Hussain N, Sufian MA, Jung J, Park SM, Kim N. Isolation and gain improvement of a rectangular notch UWB-MIMO antenna. Sensors. 2022;22:1460.
Khalid M, Iffat Naqvi S, Hussain N, Rahman M, Fawad Mirjavadi SS, Khan MJ, Amin Y. 4-Port MIMO antenna with defected ground structure for 5G millimeter wave applications. Electronics. 2020;9:71.
Sediq HT, Nourinia J, Ghobadi C. A cat-shaped patch antenna for future super wideband wireless microwave applications. Wirel Pers Commun. 2022;125:1307–33.
Ayman RS, Wael AEA, Ahmed AI. Minimally coupled two–element MIMO antenna with dual band (28/38 GHz) for 5G wireless communications. J Infrared Millim Terahertz Waves. 2022;43:335–48. https://doi.org/10.1007/s10762-022-00857-3.
Ali W, Sudipta D, Hicham M, Soufian L. Planar dual-band 27/39 GHz millimeter- wave MIMO antenna for 5G applications. Microsyst Technol. 2021;27:283–92.
Alnemr F, Mai FA, Abdulhamed A. A compact 28/38 GHz MIMO circularly polarized antenna for 5G applications. J Infrared Millim Terahertz Waves. 2021;42(3):338–55.
Aghoutane B, Sudipta D, Mohammed E, Madhav BTP, Hanan EF. A novel dual band high gain 4-port millimeter wave MIMO antenna array for 28/37 GHz 5G applications. AEU-Int J Electron Commun. 2022;145(4):154071.
Rafique U, Shobit A, Nasir N, Hisham Kh., and, Khalil U. Inset-fed Planar antenna array for dual-band 5G MIMO applications. Progress Electromagnet Res C. 2021;112:83–98.
Ali WA, Ibrahim AA, Ahmed AE. Dual-band millimeter Wave 2 × 2 MIMO slot antenna with low mutual coupling for 5G networks. Wirel Pers Commun. 2023;129:2959–76.
Sghaier N, Belkadi A, Hassine IB, Latrach L, Gharsallah A. Millimeter-wave dual-band MIMO antennas for 5G wireless applications. J Infrared Millim Terahertz Waves. 2023;44:297–312.
Hussain M, Awan WA, Ali EM, Alzaidi MS, Alsharef M, Elkamchouchi DH, Alzahrani A, Abo Sree F, M,. Isolation improvement of parasitic element-loaded dual-band MIMO antenna for Mm-wave applications. Micromachines. 2022;13:1918.
Bilal M, Naqvi SI, Hussain N, Amin Y, Kim N. High-isolation MIMO antenna for 5G millimeter-wave communication systems. Electronics. 2022;11:962.
Acknowledgements
The authors would like to thank the respected editors and the reviewers for their helpful comments.
Funding
Open access funding provided by The Science, Technology & Innovation Funding Authority (STDF) in cooperation with The Egyptian Knowledge Bank (EKB). None.
Author information
Authors and Affiliations
Contributions
AConceptualization, R.H.E.-A., and A.A.M; methodology, A.A.M; software, R.H.E.-A.; validation, R.H.E.-A.; formal analysis, R.H.E.-A. and A.A.M; investigation, R.H.E.-A. and A.A.M; resources, R.H.E.-A.; data curation, R.H.E.-A. and A.A.M; writing—original draft preparation, A.A.M; writing—review and editing, R.H.E.-A.; visualization, R.H.E.-A.; supervision, R.H.E.-A. All authors have read and agreed to the published version of the manuscript.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing interests.
Additional information
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
About this article
Cite this article
Elabd, R.H., Megahed, A.A. Isolation enhancement of a two- orthogonal printed elliptical slot MIMO antenna array with EBG structure for millimeter wave 5G applications. Discov Appl Sci 6, 222 (2024). https://doi.org/10.1007/s42452-024-05881-7
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s42452-024-05881-7