Performance degradation of terahertz channels in emulated rain

The ever-increasing capacity demand (up to Tbps in the foreseeable future) in wireless connectivity can supposed be satisfied by terahertz communications in the band from 100 GHz to 10 THz. This has been studied over short channel distances in laboratories using higher order modulation formats (QPSK, QAM). However, only very few reports on the THz channel performance in outdoor adverse weathers conditions are available due to the involved experimental difficulties. In this article, we report the performance of terahertz channels in emulated rain by utilizing a broadband pulse source and a 16-QAM modulated data stream. We observe that, a not precisely known of raindrop size distribution can be a major source of uncertainty for theoretical precipitation of power attenuation and bit error rate (BER). We also find that the channel degradation in rain is mainly due to power attenuation.