8x8 Massive Multiple Input Multiple Output (MIMO) Antenna Array with Diamond-Ring Slot for 5G and 6G Cellular Applications

Abstract

In this research paper, an 8x8 antenna Massive MIMO array, with diamond ring slots elements for 5G and 6G cellular networks has been designed using Computer Simulation Technology (CST) Microwave Studio Software. The configuration of the design consisting of eight double-fed diamond ring slot antenna elements placed at different corners of the printed circuit board (PCB). A low cast FR-4 (lossy) dielectric with an overall dimension of 75x150 mm² is used as the designed substrate. Moreover, a common ground of copper pure (lossy) metal is also used. For antenna elements copper annealed material is used to get better results in very low cost and for the purpose of easy fabrication. The antenna elements are fed by 50 ohms microstrip feedline. The lower cutoff frequency of the array is almost 3 GHz while the upper cutoff frequency is almost 4.4 GHz. So, the overall impedance bandwidth i.e. at S₁₁= -10 dB, of the design is approximately 1200 MHz which is very efficient for future 5G and 6G cellular communication networks. The characteristics impedance and operation impedance of the design are very close to each other i.e. 50 ohms which shows very minute impedance mismatching. The value of the Scattering Parameter or S-parameter in the given bandwidth is around -15 dB which is an optimum value for this array. The value of Voltage Standing Wave Ratio (VSWR) also lies the threshold value of 2. The radiation efficiency of the array is almost 80%, while its total efficiency is equal to 75%. The resonance frequency of the array is 4 GHz which is very efficient and reliable for future 5G and 6G cellular wireless networks. Farfield directivity of the array is 4.4 dBi while farfield gain of the array is 3.44 dBi.  This array can easily be used for 5G applications. For the combined and collective pattern of the overall structure the post processing is applied in CST to achieve a narrow beam in particular direction. The resultant intense beam can be sent in any particular direction using the beamforming technique.