Microstrip Antennas for Next Genertion Wireless Devices

Due to great demands for higher data rates and better bandwidth utilization in wireless communication systems, it's necessary to move forward a further step to a new generation, i.e. the fifth generation of wireless networks, 5G. This paper proposes two compact, bandwidth efficient, rectangular microstrip patch antennas, implemented on RT/Duroid 5880 substrate with a dielectric constant of $\varepsilon_{\mathrm{r}}=2.2$ and resonate at millimeter-wave frequency bands for targeting 5G broadband communications. The first proposed antenna is a tri-band antenna. This antenna has a small size of $8\times 8\times 0.6\ \mathrm{mm}^{3}$. Three impedance bandwidths of 2.2175GHz (7.17%), 3.4542 GHz (7%) and 3.1557 GHz (5.52%) at resonant frequencies of 30.9 GHz, 49.2 GHz and 57.3 GHz respectively are achieved. Moreover, a maximum achievable gain is 7.09 dBi, 7.6 dBi and 8.5 dBi at the previous resonant frequencies. The second antenna is also very compact with an overall size of $2.9\times 3\times 0.381\ \mathrm{mm}^{3}$, which operates at 60.9 GHz frequency band. A maximum gain of 7.6 dBi and a total bandwidth of 4.5269 GHz (7.43 % from center frequency) below -10dB are obtained. The compactness of these two proposed antennas enables them to be integrated into handheld mobile units. The design process of the proposed antennas is achieved by HFSS simulator.