A Dual-Band Millimeter-Wave Antenna for 5G

Mobile Applications
Chong-Zhi Han, Guan-Long Huang, Tao Yuan Chow-Yen-Desmond Sim
Guangdong Provincial Mobile Terminal Microwave and Department of Electrical Engineering
Millimeter-Wave Antenna Engineering Research Center Feng Chia University, Taichung 40724, Taiwan
College of Information Engineering
Shenzhen University, Shenzhen 518060, P.R. China

Abstract—In this work, a microstrip antenna suitable for

broadband millimeter wave mobile communication is proposed.
The microstrip antenna is fed by a coplanar waveguide (CPW)
structure with a matching port connected to a 50-Ω resistor. The
operating bandwidth of the antenna is able to cover both the 28
GHz and the 39 GHz bands for 5G millimeter wave applications.
In addition, an eight-element array is developed and studied.
Results show that the array can cover the beamwidth from -30°
to 30° in yoz-plane, which can meet the beamforming
requirement for the 5G wireless communications.

Keywords—dual-band; microstrip antenna; millimeter wave

antenna; beamforming.

I. INTRODUCTION
The fifth-generation (5G) wireless communication antennas
have aroused more and more attention in recent years.
Millimeter-wave (mmW) antenna system is one of the vital
components for the 5G communication due to its high-speed
data transmission rate and low latency. Lots of researches focus Fig. 1. Configuration of the antenna.
on this topic and several mmW antennas are also proposed [1]-
[6]. Particularly, a notch antenna and an aperture-coupled patch
antenna have been proposed to operating at mmW frequencies II. ANTENNA STRUCTURE
of the 5G networks in [1]. Furthermore, a low-complexity The configuration of the antenna element is shown in Fig. 1.
metallic tapered slot antenna covering 24.25-28.35 GHz band The antenna is composed of three layers where a 0.256 mm
is proposed in [2]. The beamforming characteristic is studied in thick dielectric substrate (εr=4.4) is located at the middle while
the paper while the bandwidth can only be applied to work for the top layer and the bottom layer are both copper layers. The
the 28 GHz band. Another broadband antenna for 5G mmW bottom layer is highlighted in dark gray color and that of the
applications mentioned in [3] uses a U-slot resonator in the top layer is in light gray color. A 50-Ω resistor is connected to
ground to achieve a wider bandwidth. However, the bandwidth the edge of the bottom layer acting as a matching port as shown
is not sufficient to cover either the 28 GHz or 39 GHz mmW in Fig. 1. The strip at bottom layer is 3.6 mm long. The
bands. The antenna proposed in [5] shifts the resonating coupling effect between the top layer and the bottom strip helps
frequency to 38.6 GHz and 70 GHz. Currently, there are the antenna to generate a broadband input impedance
seldom antennas can cover the 28 GHz and 39 GHz bands characteristic. An aperture is opened at the top layer with an
simultaneously. From this point of view, the main object of the area of 4 × 6 mm2. The feeding structure of the antenna is
work is to promote a dual-band mmW antenna for 5G mobile integrated with two strips: the one near to the feeding port is
devices. 2.65 mm long with a width of 0.8 mm; and another strip near
The antenna with a dual-band or broadband characteristic the slot has a size of 1.75× 0.4 mm2. A coplanar waveguide
would be of great significance in the 5G mobile (CPW) structure is utilized to feed the antenna at top layer. The
communications. In this work, a dual-band mmW microstrip distance between the feeding strip and the coplanar ground
antenna is proposed with a small size of 4×9.45×0.26 mm3. plane is 0.1 mm. All the abovementioned parameters are
The beamforming characteristic is also studied by simulation to studied and optimized by CST Microwave Studio®.
verify the antenna element is a good candidate for terminal
devices.

978-1-7281-0692-2/19/$31.00 ©2019 IEEE 1083 AP-S 2019

 (a)

Fig. 2. Simulated S11 result.

(b)
Fig. 4. Radiation pattern for 8-element array at 39GHz: (a) 110° phase
shift for the adjacent elements; (b) 0° phase shift for the adjacent elements.

(a) Fig. 4, the main lobe of the radiation pattern is able to shift
significantly with a stable realized gain by adjusting the phase
difference among the antenna elements. The simulated gain of
the 8-element array at 39 GHz is up to 13.8 dBi, which is
potentially sufficient to apply in the 5G mmW communication.

IV. CONCLUSION
The propsed antenna has broadband characteristic to cover
both 28GHz and 39GHz bands for 5G communication. An 8-
element array is also studied to verify the proposed antenna can
be a good candicate for terminal device applications.

(b)
Fig. 3. Simulated radiation pattern results: (a) at 28GHz; (b) at 39GHz.
REFERENCES
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