Neutralization technique based two and four port high isolation MIMO antennas for UWB communication

A Review on Different Techniques of Mutual Coupling Reduction Between Elements of Any MIMO Antenna. Part 2: Metamaterials and Many More

“…A simple meandered‐shaped metallic stripline (Y. Yu et al., 2016) has been used as NL to cancel coupling between circular rings shaped radiating patch antennas as represented in Figure 11a. An NL comprises two metallic strips and a rectangular patch (Tiwari, Singh, & Kanaujia, 2019; Tiwari, Singh, & Kanaujia, 2019), as described in Figure 11b has been used between the UWB‐MIMO antenna elements. A simple metallic strip was connecting the feedline (Luo et al., 2019; Ou et al., 2017); triple branch NL along with DGS (Mondal et al., 2018), as represented in Figure 12a; a microstrip neutralization network (H. Wang et al., 2014) as depicted in Figure 12b; NL along with inverted I‐ground slots (W. Jiang et al., 2019); a simple NL connecting the ground of CPW‐Fed tri‐band MIMO antenna (Saleh et al., 2017); crossed NL (S. Wang & Du, 2015); typical NL (Su & Lee, 2011); a neutralization ring (Kayabasi et al., 2018) and a group of three NLs (Y. Wang & Du, 2014) have been used to cancel the coupling from one antenna to another radiating patch antenna.…”

“… (a) Meandered‐shaped metallic NL (Y. Yu et al., 2016) (b) NL comprises of two metallic strips and a rectangular patch (Tiwari, Singh, & Kanaujia, 2019; Tiwari, Singh, & Kanaujia, 2019). NL, neutralization line.…”

A wideband four‐port multiple‐input‐multiple‐output slot antenna for WLAN / WiFi / 5G below 6 GHz applications

“…High mutual coupling can increase antenna correlation, trigger severe impedance mismatch, and distort the radiation patterns 16 . Techniques such as neutralization lines 17‐19 defected ground structures 20,21 and meta‐structures 22‐24 have been adopted to decrease mutual coupling in a MIMO antenna scheme.…”

Two Port Compact Mimo Antenna for Ism Band Applications

“…Mostly preferred and frequently used MC techniques are presented here. For example, use of a defected ground structure (DGS) can reduce MC up to −55 dB [5]; dielectric resonator antenna can reduce MC up to −25 dB [6], complementary split-ring resonator (CSRRs) can reduce MC up to −22 dB [7], neutralization lines reduce MC up to −23 dB [8,9], engineered parasitic patch or slot element can reduce MC by −22 dB [10], reconfigurable antenna can reduce MC up to −47 dB [11], electromagnetic bandgap (EBG) can reduce MC up to −53.7 dB [12], engineered metamaterial can reduce MC up to −42 dB [13], and decoupling networks can reduce MC up to −32 dB [14], respectively. DGS and EBG are preferred methods to reduce MC.…”