In this paper, an irregular octagonal two-port MIMO patch antenna is designed specifically for New Radio (NR) 5G applications in the mid-band sub-6 GHz. The proposed antenna comprises an irregularly shaped patch antenna equipped with a regular 50-ohm feed line and a parasitic strip line antenna, and is partially grounded. Jeans material serves as a substrate with an effective dielectric constant of 1.6 and a thickness of 1 mm. This material is studied experimentally. The proposed antenna design undergoes analysis and optimization using the ANSYS HFSS tool. Furthermore, the design incorporates the influence of the slot on both the ground plane and the parasitic strip line to optimize performance, enhance isolation, and improve impedance matching among antenna elements. The dimensions of the jeans substrate are 40 mm × 50 mm. The simulated impedance bandwidth ranged from 3.6 GHz to 7 GHz and the measured bandwidth was slightly narrower, from 4.35 GHz to 7 GHz. The simulation results demonstrated an isolation level greater than 12 dB between antenna elements, while the measured results reached 28.5 dB, and the peak gain for this proposed antenna stood at 6.74 dB. These qualities made this proposed antenna suitable for various New Radio mid-band 5G wireless applications within the sub-6 GHz band, such as N79, Wi-Fi-5/6, V2X, and DSRC applications.

A compact dual-band monopole antenna is proposed for the Internet of Things (IoT) and Sub-6 GHz band 5G applications. The proposed antenna is comprised of a simple inverted C-shaped tapered microstrip line and partial ground. The overall FR4 substrate dimensions are $40\ \text{mm}\ \times\ 12\ \text{mm}\ \times\ 1.6 \text{mm}$ . The antenna is designed and optimized in the Ansys HFSS tool. The inverse C-shaped microstrip line radiates from 4.8 GHz to 5.7 GHz and the L-shaped microstrip line radiates from 2.3 GHz to 2.6 GHz at higher and lower bands. The proposed antenna demonstrates enhanced performance in terms of reflection coefficient (<−10dB), radiation patterns, peak gain (2.7 at 2.4 GHz and 1.8 at 5.2 GHz), and radiation efficiency (95% at 2.4 GHz and 93% at 5.2 GHz). The results of the prototype test show significant correlations with the simulation results. The novel, compact antenna is able to be combined with IOT sensors, RF modules at the frequency of 2.4 GHz (ISM band) and sub-6 bands for 5G WLAN applications.

In this article, a novel multi-slot 2-port and 4-port compact wideband MIMO antennas are designed for 5G communication in the sub-6 GHz band. The multi-slot antenna contains a rectangular patch with two square cuts at the lower corner of it. Here, two rectangular slots, one at the top edge and the other near the bottom edge of the antenna. The orthogonal placement technique helps to provide initial isolation between ports. Further, a P-shaped stub is added to the top edge of the antenna element to achieve very high isolation among 4 antennas. The FR4 substrate’s overall dimensions are considered 56 x 56 x 1.6 mm3. The proposed 4-port multi-slot antenna achieved isolation of > 15 dB in the operating frequency band from 3.60 GHz – 7.33 GHz. The 4-port multi-slot prototype results and its simulated results are almost similar. The radiation patterns in elevation and azimuth planes are stable, a peak gain and high efficiency are 5.2 dB and 95% respectively. This antenna performance can be envisaged for N78/79, Wi-Fi 5/6, and Vehicle2X/DSRC bands.

In this paper, a stub-loaded 2-port MIMO antenna is introduced for applications across the n77 (3.30–4.20 GHz), n78 (3.30–3.80 GHz), n79 (4.40–5.00 GHz), Wi-Fi-5 (5.15–5.85 GHz), and 7–7.83 GHz bands. It comprises a microstrip line feed, a two-port stub-loaded MIMO antenna, and an FSS (frequency selective surface) filter. The antenna designed with dimensions of 37.5 × 32 mm ² on an FR-4 epoxy substrate PCB with a thickness of 1.6 mm. The FSS structure contains 16 circular vertex square-shaped unit cells arranged in a 4×4 array, with a size of 50×50×1.6 mm ³ , and due to stub and FSS loading, gain, bandwidth, and isolation improved significantly. The design process utilizes the ANSYS HFSS tool, and the antenna operates within the frequency ranges of 3.36–5.76 GHz and 7–7.83 GHz. Moreover, the isolation value achieves a minimum of −18 dB and −15 dB for nearly simulated and measured results across the entire band. Peak gain reaches a maximum of 6 dBi and a minimum of 3.35 dBi due to FSS loading. Radiation patterns exhibit high directivity at lower and higher frequencies and nearly omnidirectional behavior at middle frequencies, attributed to the passband filter characteristics of the FSS. The MIMO diversity parameters ECC and CCL are verified to be within acceptable limits. This innovative antenna can envisaged for sub-6 GHz band 5G applications.