Abstract—In order to achieve next-generation wireless communication standards, especially for small cell base stations, one of the key needs is the construction of a wideband, high-gain multiple antennas operating at the mm-wave frequency (24 GHz – 28 GHz). In essence, a closely spaced antenna makes up a multiple antenna system. The performance of the system as a whole is lowered by closely placed antennas because they increase mutual interaction. Metamaterial, parasitic elements, and defective ground are examples of decoupling structures that are utilised to lessen this contact. This work makes use of no decoupling structures still achieving required isolation. This work includes the design of a 2 × 2 Microstrip Patch Antenna with a U-slot that provides self-isolation when deployed. The space between the elements is taken as λ/4. The performance criteria used to evaluate the planned multiple antenna system include the envelope correlation coefficient, diversity gain, channel capacity loss, and total active reflection coefficient. The Elliptic-Curve Cryptography (ECC) is evaluated using both s-parameter and far-field patterns, and the results are less than 0.05 and 0.5. In the required mm-wave range, the channel capacity loss is less than 0.5bit/s/Hz, and the total active reflection coefficient is less than -10dB. Because no decoupling structure is used, the multiple antenna system is compact. The antenna can be used as a pico cell or femtocell base station antenna for mm-wave communication.


Keywords—U-slot loaded-microstrip patch antenna, mm-wave band, self-isolation, Multiple Antenna System (MIMO), small cell base station


Cite: Priyadarshini K. Desai *, Keerti Kulkarni, and Champa P. N., “Design and Analysis of Wideband, High Gain, Self-Isolated Multiple Antenna for mm-Wave Application," Journal of Communications, vol. 21, no. 1, pp. 12-19, 2026.

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