Characteristics of fixed THz wireless links in atmosphere

Broadband wireless access over short distances with fixed THz wireless links is very promising. A new model of atmospheric transmission of terahertz communication is developed based on the radiation transmission theory and the continuum absorption phenomenon using data from the HITRAN database. The attenuation, the path loss and the channel capacity of THz atmospheric propagation are investigated by means of numerical simulation. The THz wave atmospheric attenuation experimental results obtained with the THz-time domain spectroscopy (THz-TDS) technique is analyzed by this new model. The intensity and the location of the observed absorption lines are in good agreement with the spectral databases. Five channels ranging from 100 to 900 GHz are analyzed. Nevertheless, contrary to the wireless links in the lower GHz-bands, the transmittable data rates are reduced in this frequency range because of the high free-space path loss and attenuation due to molecules in air or water droplets. As demonstrated here, high transmission data rates larger than 10 Gbps can be reached via these channels within short distances if antennas with high gains are used.