Broadband sub‐6 GHz flower‐shaped MIMO antenna with high isolation using theory of characteristic mode analysis (TCMA) for 5G NR bands and WLAN applications

Abstract

A small size neutralization line integrated flower-shaped MIMO antenna is designed and analyzed for sub-6 GHz type 5G NR frequency bands like n79 (4400-5000 MHz), n78 (3300-3800 MHz), n77 (3300-4200 MHz), and WLAN (5150-5825 MHz) applications. The novel approach of theory of characteristic mode analysis (TCMA) is introduced to provide physical insight of the designed structure and its characteristics behavior. Due to the suggested modifications in the geometry, the isolation among the patches is greatly increased.The overall miniaturized dimension of the MIMO antenna is 25 Â 40 mm 2 . The edge-edge spacing among the elements is 0.0233λ. The prototype antenna is fabricated and measured that shows good agreement compared with simulated results. The designed MIMO antenna without the presence of decoupling structure offers an isolation of 28 dB, gain of 3.6 dBi, and radiation efficiency of 69.7% at the resonant frequency. The proposed MIMO antenna covers a broad range of frequency band from 3.296 to 5.962 GHz with À10 dB impedance bandwidth of 2666 MHz and maintains a good isolation of greater than 50 dB for the entire operating band. The tested radiation efficiency and gain are 85.3% and 6.22 dBi at 3.5 GHz. Moreover, the diversity parameters of the neutralization line integrated MIMO antenna, that is, channel capacity loss (CCL) isolation, mean effective gain (MEG), total active reflection coefficient (TARC) diversity gain (DG), and envelope correlation coefficient (ECC), are analyzed and discussed in this article.

Deep learning assisted fractal slotted substrate MIMO antenna with characteristic mode analysis (CMA) for Sub-6 GHz n78 5 G NR applications: design, optimization and experimental validation

“…For conductor analysis, the characteristic mode theory was proposed in the year 1971 [40,41] and has been extensively utilized for the MIMO antenna design [16,[42][43][44][45]. In this current MIMO antenna analysis, various parameters of characteristic mode analysis like characteristic angle, eigenvalues and modal significance are introduced.…”

“…The characteristic mode analysis parameters of the proposed MIMO antenna are displayed in figure 4. For an ideal conductor the total current J expresses the linear superposition related to the currents for all modes of the design system [16].…”

“…In this circumstance, several design methodologies for MIMO antenna configurations have been adopted and implemented by the researchers for different wireless communication standards including 5G systems. The reported designs include arrangement of inverted-F MIMO antenna [1], FSS integrated 3-dimensional MIMO antenna incorporating folding technique and meandered DGS [2], hexagonal slot loaded MIMO antenna for 5NR mobile applications [3], metamaterial inspired textile MIMO radiator with high isolation [4], MIMO array antenna system with diamond ring slot elements for 5G smartphones [5], 2´1 MIMO array of folded patch with a shorting wall and 3D U-slot cut folded monopole feed [6], bow-tie dipole pair designed with trapezoidal and U-shaped slots in presence of an AMC reflector [7], Split ring resonator based MIMO antenna [8], complementary split ring resonator (CSRR) loaded MIMO radiator [9], MIMO antenna with hexagonal slot loaded patches and parasitic elements [10], eight port square-ring slot radiator MIMO array antenna [11], circle shaped MIMO radiator using DGS [12], MIMO array antenna [13], fractal MIMO antenna [14], 4-port quad element based MIMO antenna with suppression of multi-tone interference [15], flower shaped MIMO radiator using theory of characteristics mode analysis [16], eight element MIMO antenna based on stepped impedance resonators (SIRs) [17], half-circular U-shaped slots based MIMO antenna for wireless systems [18], 8 element MIMO antenna system consisting of monopole-type meandered branch and an inverted U-shaped self-isolated antenna branch [19], minkowski shape MIMO radiators [20,21], kotch fractal UWB MIMO [22], V-slotted FSS integrated MIMO antenna with quare spiral parasitic elements [23], CPW fed symmetrical patch based MIMO antenna with slits incorporated ground plane [24], MIMO antenna with arc shaped slots based patches with defected ground structures [25], dual-antenna system with a driven branch, parasitic ground branch, and neutralization line [26], and fractal MIMO radiator using curves related to Koch hybrid and minkowski [27]. In literature, the design proces...…”

Three‐element ultrawideband MIMO antenna based on shared‐radiator structures with high efficiency and gain

“…Previous literature has reported several MIMO antennas, how to realize high isolation between the radiating elements becomes the key difficulty in designing the UWB MIMO system. Different decoupling techniques have been discussed, such as defected ground structures, [4][5][6][7] fence-type decoupling structure, 8 short ground strip, 9 carbon black film, 10 neutralized line, 11,12 rectangular vertical arm in the ground plane, 13 and etching a slot in the ground plane. [14][15][16] Reported planar UWB MIMO antennas [17][18][19][20] have achieved good isolation without additional decoupling structures.…”

Design and analysis of metasurface-based CPW-Fed UWB MIMO antenna for wireless communication systems

“…With the continuous exploration of researchers, the methods to solve the mutual coupling of MIMO antenna have been summarized one after another. In [10,11], a technique called neutralization-line was described that neutralized the coupled reverse current. The parasitic structure was used to enhance isolation in [12,13].…”