Triple-band stub loaded patch antenna with high gain for 5G Sub-6 GHz, WLAN and WiMAX applications using DGS

Microstrip antennas have become ubiquitous in today's wireless communication world due to their low profile, low cost, and simplicity in fabricating on circuit boards. However, poor performance characteristics, such as limited bandwidth, low power handling capabilities, and low gain, limit their applicability in various instances. Path loss will be substantial in 5th generation (5G) wireless communication due to the utilization of high-frequency bands. A high-gain antenna with a small size is necessary to address this issue. A compact tri-band, slotted monopole antenna with high and consistent gain employing a defected ground plane structure (DGS) has been investigated and implemented in this study. This proposed antenna uses three inverted L-shaped stubs connected to the radiating element to cover the desired bands while keeping the antenna size small. The designed antenna has two key characteristics: (i) wide bandwidth and (ii) reasonable gain. The antenna covers 2.45 and 5.6 GHz WLAN, 2.4 GHz Wi-Fi, 2.5 and 5.2 GHz WiMAX and 3.7 GHz Sub-6 GHz of 5G for mobile communication. The overall substrate size of the antenna is 30 ? 17 ? 1.6 mm3and the electrical dimensions are 0.49 ?L ? 0.28 ?L ? 0.026 ?L, where ?L is the free space wavelength at 2.45 GHz. The measured reflection coefficient (S11 < -10dB) covers 2.4 - 2.52 GHz (bandwidth 112 MHz) and 3.4 - 4.1 GHz (bandwidth 700 MHz) and 5.2 - 6.6 GHz (bandwidth 1359 MHz) with a fractional bandwidth of 5.1 % at lower frequency band, 18.6 % at mid frequency band and 23.7 % at high frequency band. A prototype antenna has also been developed using an inexpensive, low-profile 1.6 mm thick FR-4 (?r = 4.4) substrate. The measured peak gains achieved are 1.35 dB at 2.45 GHz, 2.55 dB at 2.65 GHz and 3.8 dB at 5.5 GHz. The simulated results have been validated against actual experimental measurements, and the outcomes are consistent and match with certainty. The proposed antenna design is very compact and easy to fabricate due to the absence of vias.