Novel tri-band series fed microstrip antenna array for THz MIMO communications

A novel tri-band series fed microstrip two-element array antenna is reported in this paper for Terahertz (THz) multiple-input multiple-output (MIMO) communications. Each series-fed array consists of four radiating sections constructed using graphene material. The radiating sections consist of a square loop loaded with a diamond-shaped radiator to offer multi-frequency operation. The proposed antenna operates at 2.3 THz, 3.2 THz and 4.5 THz. The antenna offers an effective 10 dB reflection coefficient bandwidth of 38 GHz, 43 GHz and 60 GHz centred at 2.3 THz, 3.2 THz and 4.5 THz respectively. The isolation enhancement between the antenna elements is achieved using a serpentine resonator. The port-to-port isolation is greater than 15 dB in all the operating bands. The realized antenna gain is greater than 5 dBi in all the operating frequencies. The MIMO metrics of the proposed two-element antenna array is estimated and the results are presented. The envelope correlation coefficient (ECC) is less than 0.2, the diversity gain is close to the theoretical limit of 10 dB and the mean effective gain is close to unity.

Automated summary

A novel tri-band series-fed microstrip two-element array antenna for Terahertz MIMO communications is proposed, offering multi-frequency operation at 2.3 THz, 3.2 THz, and 4.5 THz. The antenna features effective reflection coefficient bandwidths of 38 GHz, 43 GHz, and 60 GHz at the respective frequencies, with isolation enhancement achieved using a serpentine resonator. The MIMO metrics show low envelope correlation coefficient, close-to-theoretical diversity gain, and near-unity mean effective gain.