In this paper, a compact and conformal MIMO antenna EM wave with four ports for dual-band (28/38) 5G applications is introduced and can be deployed for 5G infrastructure. To begin with, a single element resonating at 28 GHz is designed which radiates Electromagnetic-Energy efficiently. The antenna measures 12 × 12 × 0.254 mm3 and is made of Rogers RT-5880 substrate possessing thickness of 0.254 mm. Using slot etching and stub insertion, the antenna dimensions are optimized to achieve resonance at 38 GHz. As a result, the single element resonated at both 28/38 and 39 GHz frequencies. The peak realized gain achieved is 5.9 dB for 28 GHz, 6.0 dB for 38 GHz, and 4.9 dB for 39 GHz with a single antenna element. An element is analyzed to see if it can be used in a MIMO configuration with two orthogonally placed elements that provide -30 dB of isolation for 28/38 and 39 GHz. Later, the design was expanded to include four ports with dimensions of 24 × 24 × 0.254 mm3. The elements are spatially and orthogonally placed to provide the required isolation of less than -20 dB for the necessary frequency bands. The proposed four-port antenna has been analyzed for its conformality at different angles. The minor change in its impedance bandwidth confirms that it is conformal and can be used in on–off body applications. Additionally, the Specific Absorption Ratio (SAR) for three intended frequencies has been analyzed to be less than 0.0555W/Kg for a single element and less than 0.0295 W/Kg for the four-port proposed MIMO. This ensures safety if applied for human applications. The MIMO parameters have been calculated with envelope correlation coefficient for dual bands (ECCDB) to be less than 0.01, Directive gain for dual bands (DGDB) being 9.98 dB for n261 and 9.99 dB for n260 band, channel capacity loss(CCLDB)of less than 0.4b/s/Hz for n261 and less than 0.2b/s/Hz for n261 band, total active reflection coefficient with values less than zero(TARCDB)and mean effective gain (MEGDB)values ranging from −3 to −4 dB, all within the standard acceptable values are achieved. The simulation results have been compared with the measured results, which validates the MIMO design applicable for 5G applications in millimeter frequency range (FR2). Graphical abstract A Ultra Compact Four-Port MIMO Antenna of Dimension 24×24×0.254 mm3 covering n260 and n261 mmWave band is fabricated and investigated. The MIMO antenna offers high diversity performance by placing the radiating elements in orthogonal-sequence. The MOMO antenna is verified for conformal applications and is subjected to Specific-Absorption-Rate at both mmWave bands with values corresponding to 0.0242 at 28.0GHz, 0.0282W/Kg at 38.0GHz and 0.0294W/Kg at 39.0GHz. The above features of the MIMO antenna is useful for Conformal On-Body applications.

Inverted marquee shaped compact and conformal four-port configured mm-wave MIMO antenna for 5G applications at 28/38 GHz frequencies (n261 and n260)

期刊论文
发表日期：

2025年2月12日

查看全文

Parminder Kaur,
Shivani Malhotra,
Manish Sharma

摘要

In this paper, a compact and conformal MIMO antenna EM wave with four ports for dual-band (28/38) 5G applications is introduced and can be deployed for 5G infrastructure. To begin with, a single element resonating at 28 GHz is designed which radiates Electromagnetic-Energy efficiently. The antenna measures 12 × 12 × 0.254 mm³ and is made of Rogers RT-5880 substrate possessing thickness of 0.254 mm. Using slot etching and stub insertion, the antenna dimensions are optimized to achieve resonance at 38 GHz. As a result, the single element resonated at both 28/38 and 39 GHz frequencies. The peak realized gain achieved is 5.9 dB for 28 GHz, 6.0 dB for 38 GHz, and 4.9 dB for 39 GHz with a single antenna element. An element is analyzed to see if it can be used in a MIMO configuration with two orthogonally placed elements that provide -30 dB of isolation for 28/38 and 39 GHz. Later, the design was expanded to include four ports with dimensions of 24 × 24 × 0.254 mm³. The elements are spatially and orthogonally placed to provide the required isolation of less than -20 dB for the necessary frequency bands. The proposed four-port antenna has been analyzed for its conformality at different angles. The minor change in its impedance bandwidth confirms that it is conformal and can be used in on–off body applications. Additionally, the Specific Absorption Ratio (SAR) for three intended frequencies has been analyzed to be less than 0.0555W/Kg for a single element and less than 0.0295 W/Kg for the four-port proposed MIMO. This ensures safety if applied for human applications. The MIMO parameters have been calculated with envelope correlation coefficient for dual bands (ECC_DB) to be less than 0.01, Directive gain for dual bands (DG_DB) being 9.98 dB for n261 and 9.99 dB for n260 band, channel capacity loss(CCL_DB)of less than 0.4b/s/Hz for n261 and less than 0.2b/s/Hz for n261 band, total active reflection coefficient with values less than zero(TARC_DB)and mean effective gain (MEG_DB)values ranging from −3 to −4 dB, all within the standard acceptable values are achieved. The simulation results have been compared with the measured results, which validates the MIMO design applicable for 5G applications in millimeter frequency range (FR2).

Graphical abstract

A Ultra Compact Four-Port MIMO Antenna of Dimension 24×24×0.254 mm3 covering n260 and n261 mmWave band is fabricated and investigated. The MIMO antenna offers high diversity performance by placing the radiating elements in orthogonal-sequence. The MOMO antenna is verified for conformal applications and is subjected to Specific-Absorption-Rate at both mmWave bands with values corresponding to 0.0242 at 28.0GHz, 0.0282W/Kg at 38.0GHz and 0.0294W/Kg at 39.0GHz.

The above features of the MIMO antenna is useful for Conformal On-Body applications.