Abstract:
The fifth-generation (5G) of cellular communication networks is desired to operate at the mm-wave
frequency band, which has different propagation constraints like relatively high path losses and atmospheric
absorption. To mitigate these effects, it is crucial to construct a low-cost and low-profile antenna array
which maintains high performance over a broad frequency spectrum. In this respect, microstrip patch
antenna (MPA) arrays are considered as a candidate antenna type. But, the gain of MPA is low, the
bandwidth is too narrow and the integration of a large of elements in the array leads to increased sidelobe
level, which decreases radiation efficiency and directivity of the antenna. Besides, the substrate thickness
deteriorates the antenna's bandwidth and radiation efficiency by increasing the surface wave and spurious
feed radiation. Various design techniques of MPA were reported to alleviate these limitations and improve
its performance for 5G communication systems. These include using the slotted patch, defected ground
plane, increasing the array elements, changing substrate material, and feeding techniques. But, obtained
performance is low for 5G communications. The existing studies' main emphasis was on single element
and linear rectangular MPA arrays. A few studies have been carried out to explore the extensive design of
planar MPA arrays to improve the bandwidth, gain, and scanning capability of a one-dimensional
rectangular MPA array. Thus, to address these challenges, in this study, the performance analysis of a single
element, planar 2x2, 4x4, and 8x8 rectangular MPA arrays are presented by introducing a semi-elliptical
slot structure on a radiating patch and ground plane, and tuning key dimensions of the antenna. All the
proposed MPA arrays are simulated using CST-MW studio and found that the return loss, bandwidth, and
gain of the a semi-elliptical slotted single element MPA are -37.784dB, 1.132GHz, 7.128dBi, respectively.
The gain, bandwidth, and total efficiency of the studied 2x2, 4x4, and 8x8 MPA array are about 13.24dBi,
16.54dBi, 21.45dBi; 1.33GHz, 1.461GHz, 1.561GHz; 97.03%, 81.72%, 69%, respectively. Likewise, their
return loss and VSWR are -43.321dB, -40.665dB, -22.678dB; 1.014, 1.019, 1.159, respectively. The
simulation results show that the introduced semi-elliptical slot on the patch and ground plane significantly
influences the structure's current distribution. As a result, the radiation efficiency is increased and thereby
the bandwidth of the antenna. Moreover, tuning the antenna's key dimensions and etched portion affects
the bandwidth, gain, directivity, radiation efficiency, and amount of the antenna's power loss. In general,
all the proposed planar rectangular MPA arrays satisfy the requirements of a 5G antenna. As compared to
other similar workstherefore, the studied antenna provides a highly competitive and improved performance.
