Development and Performance Study of Mutually Coupled Parasitically Loaded 5G Antenna for Sub-6GHz Applications

The edge-fed monopole 5G antenna described in this article is intended for sub-6 GHz applications, with a specific focus on the n77 (3.7 GHz), n78 (3.5 GHz), and n79 (4.5 GHz) frequency bands. A novel methodology is employed to develop the antenna, which consists of binary operations on three patches (Patch1, Patch2, and Patch3), with their dimensions optimized for 3.5 GHz, 3.7 GHz, and 4.5 GHz, respectively. In order to generate an initial U-stub, Patch2 is subtracted from Patch1 followed by Patch3. Through the utilization of a coupling limb, Patch3 and the U-stub establish mutual current coupling. To remove extra bandwidth and maintain a gain more than 5 dBi, the antenna is parasitically loaded with a split-ring resonator (SRR) in a partial ground plane. The resultant antenna functions within the frequency range of 3.13 GHz to 5.06 GHz, exhibiting a maximum gain of 5.71 dBi and a maximum efficiency of 99.55%. By reducing its dimensions by 12.676% in comparison to a traditional rectangular patch antenna operating at 3.5 GHz (0.416λ₀ × 0.423λ₀ × 0.0186λ₀), the overall dimensions are as follows: 0.416λ₀ × 0.369λ₀ × 0.0186λ₀. It is worth noting that λ0 is computed at 3.5 GHz. The RLC equivalent circuit is validated using ADS software, and antenna prototype measurements accord with simulated outcomes generated by HFSS and CST software.