Multi-beam and Beamforming Terahertz Array Antenna for 6G Communication

Abstract

This chapter discusses the multi-user, multiple-input, multiple-output (UM-MIMO) technology with multi-beam and beamforming THz array antenna for 6G communication. There are four designed THz antenna models, including three models of THz beamforming microstrip array antennas and 1 THz ultrawide band MIMO antenna model with their simulation results presented. The presented THz antenna models are (1) used for THz beamforming using a 30 × 16 E-shaped radiator microstrip array antenna for the resonance frequency of 146.55 GHz. The achieved gain, impedance bandwidth, and steering angles are 23.8 dB, >41.88 GHz, and ±13.7°, respectively, (2) used for THz beamforming 30 × 16 E-shaped radiators microstrip array and bandstop and passband FSSs antenna for the resonance frequency of 136.45 GHz, and the achieved gain, impedance bandwidth, and steering angles were 26.04 dB, >33.3 GHz, and ±13.5°, respectively, (3) used for THz beamforming Rotman lens microstrip array antenna for the resonance frequency of 118–143.2 GHz, and the achieved realized gain, impedance bandwidth, and steering angles were 14.09 dB, 31.02 GHz, and ±23.8°, respectively. From error analysis, the proposed THz beamforming microstrip array antenna, gain, and bandwidth because of the predictable fabrication etching tolerance accuracy ±10 μm, the microstrip laminates frequency-pendent dielectric properties (εr) and the frequency-pendent losses (tanδ) may change by a maximum of about 2.1 dB and 6.31 GHz because of the antennas' high frequency working beyond 100 GHz. The simulation results of the primary models are verified with another kind of antenna simulator, and a good agreement is achieved, (4) used a 4-port MIMO microstrip antenna, including four antipodal Vivaldi microstrip radiators. Furthermore, the simulated results of the proposed THz MIMO antenna showed an impedance bandwidth, maximum gain at a solid angle, minimum envelope correlation coefficient (ECC), and minimum diversity gain (DG) of >1846.7 GHz, 8.66 dB, 23.48 dB, 0.000916, and 9.9965 dB, respectively. From state-of-the-art simulation results with future fabrication etching tolerance accuracy, microstrip substrate εr, and microstrip substrate tan δ deviations, which can be when an experimental verification with a prototype fabricated THz MIMO antenna, the impedance bandwidth and maximum gain can be altered by a maximum of about 1.25–2 GHz, 0.5–0.9 dB from the simulated results.