11 research outputs found
Potential key challenges for terahertz communication systems
The vision of 6G communications is an improved performance of the data rate and latency limitations and permit ubiquitous connectivity. In addition, 6G communications will adopt a novel strategy. Terahertz (THz) waves will characterize 6G networks, due to 6G will integrate terrestrial wireless mobile communication, geostationary and medium and low orbit satellite communication and short distance direct communication technologies, as well as integrate communication, computing, and navigation. This study discusses the key challenges of THz waves, including path losses which is considered the main challenge; transceiver architectures and THz signal generators; environment of THz with network architecture and 3D communications; finally, Safety and health issues
Reconfigurable Intelligent Surface Aided TeraHertz Communications Under Misalignment and Hardware Impairments
TeraHertz (THz) communications are envisioned to help satisfy the ever high
data rates demand with massive bandwidth in the future wireless communication
systems. However, severe path attenuation, transceiver antenna misalignment,
and hardware imperfection greatly alleviate the performance of THz
communications. To solve this challenge, we utilize the recently proposed
reconfigurable intelligent surface (RIS) technology and provide a comprehensive
analytical framework of RIS-aided THz communications. More specifically, we
first prove that the small-scale amplitude fading of THz signals can be exactly
modeled by the fluctuating two-ray distribution based on recent measurements.
Exact statistical characterizations of end-to-end signal-to-noise plus
distortion ratio (SNDR) and signal-to-noise ratio (SNR) are derived. Moreover,
we propose a novel method of optimizing the phase-shifts at the RIS elements
under discrete phase constraints. Finally, we derive analytical expressions for
the outage probability and ergodic capacity, respectively. The tight upper
bounds of ergodic capacity for both ideal and non-ideal radio frequency chains
are obtained. We provided Monte-Carlo simulations to validate the accuracy of
our results. It is interesting to find that the impact of path loss is more
pronounced compared to others, and increasing the number of elements at the RIS
can significantly improve the THz communication system performance