Characteristics Mode Analysis: A Review of Its Concepts, Recent Trends, State-of-the-Art Developments and Its Interpretation With a Fractal Uwb Mimo Antenna

Abstract

In this article, we present a compact and efficient diametrically-fed dual port fractal UWB MIMO antenna for portable handheld wireless devices. The electromagnetic behaviour on conducting body is analyzed through classical approach based characteristics mode analysis (CMA). Their intrinsic characteristics are explored on the basis of (a) modal surface current distributions, (b) narrow/broad bandwidth capability, and (c) radiation potentials. Concurrent analysis is persuaded on a diametricallyfed dual-port fed fractal conducting surface, which provides interesting facets on the combinatory effect of electromagnetic performance and physical behaviour on metallic radiator, metallic ground planes (unconnected/connected) and combination of two aforementioned metallic compact geometries. Theoretical insights are investigated for essential/non-essential modes existing in proposed geometry. The investigation through CMA also gives plethoric information on the feed location of antenna on modal surface currents and similar trends to capture its radiation potentials on the current nulls existing in the physical body. A broad classification of modes is explained, covering the CMA modal dynamics such as (a) characteristics angle (CA), (b) eigenvalues (EV), and (c) modal significance (MS). These additive parameters in general reflect the resemblance of Q-factor ≈ B.W. for narrowband/wideband traits, electrically/magnetically coupled energy behaviour, and radiative potential for far-field propagation. Thus, in a nutshell , it can be concluded that 'CMA provides physically intuitive guidance for the analysis and designing of antenna structures'. To support the findings highlighted in this particular study, a concise review about the theory of characteristic modes and the practical examples that use such concepts are taken into consideration.

Hybrid metasurface loaded tri‐port compact antenna with gain enhancement and pattern diversity

“…To investigate the MS conductor, Characteristics Mode Analysis (CMA) is explored 24‐26 . The modal metrics like EV and MSig are shown in Figure 12, and the predictions holds good at operating bands owing to the convergence in its modal performances.…”

Reconfigurable miniaturized UWB multiple‐input‐multiple‐output antenna system design and study using characteristics mode analysis

“…The band-notched behavior is investigated through CMA [14][15][16][17] and two working modes (NB, NM) shows distinctive modal characteristics. d. Equivalent circuit model: An equivalent circuit model of proposed antenna has been designed using lumped elements.…”

“…Hence, in this article, we have proposed an 4‐element miniaturized MIMO antenna, which has the following characteristics: Miniaturization design : The proposed 4‐element UWB MIMO antenna has a size 24 mm × 24 mm and achieves design miniaturization owing to self‐similar radiators 10 with rotationally symmetric ground configuration. Reconfigurable wide band‐notching : Using standard RF p‐i‐n diodes mounted on radiating slots 11–13 wide‐band‐rejection mode from 3.7 to 8.87 GHz is asserted in the operating spectrum. Compared to 1‐element antenna, the proposed 4‐element antenna asserts wide‐band rejection due to the dominant inductance effect in magnetically coupled Γ slots. characteristics mode analysis (CMA) investigation : The band‐notched behavior is investigated through CMA 14–17 and two working modes (NB, NM) shows distinctive modal characteristics. Equivalent circuit model : An equivalent circuit model of proposed antenna has been designed using lumped elements 18 …”

Investigation of a defected ground structure inspired wideband printed monopole mobile antenna using characteristics mode analysis

“…22 In such a case, the classical modal theory based characteristics mode analysis (CMA) helps to resolve the aforementioned issues. [22][23][24][25][26][27][28][29][30] In this article, the approach of designing mobile antenna is initiated with exploiting CMA electromagnetics for investigating crescent monopole antenna, operating in the M-mode. An L-stub operates in S-mode is integrated to combine their fundamental resonating modes to generate an I-mode with good impedance bandwidth (IBW).…”

“…To achieve such type of trade‐offs from application point of view, a thorough analysis with its understanding to certain antenna parameters that affect the system performance is required, especially dealing with the compact multi‐resonant mobile antennas, that is, getting through the physics into simulation 22 . In such a case, the classical modal theory based characteristics mode analysis (CMA) helps to resolve the aforementioned issues 22–30 …”