Broadband Channel Characterization and Estimation for Wideband Terahertz Wireless Communications

Terahertz (THz) wireless communication systems enable high-speed, low-latency operation, but they have enduring challenges for their transceivers and channels in overcoming water vapour absorption. The absorption is challenging because its sharp spectral peaks (relative to the communication bandwidth) result in large channel delay spread and frequency-selective attenuation, rendering much of the bandwidth unusable. In this work, we propose a novel channel estimation technique employing broadband characterization to equalize the effects of absorption and recover bandwidth. We simulate its performance for a system applying frequency-division multiplexing (FDM) and multiple-input-multiple-output (MIMO) technology, with the channel amplitude waveform measured in real time and the phase waveform extracted via Kramers-Kronig (KK) relations. We show that the proposed system can realize strong performance.