Beam-Tracking Challenges in THz Communications

In recent years, the demand for high data rates has increased drastically. In response to this increasing demand, higher frequencies, such as millimeter wave (mmWave) and terahertz (THz) have been considered that offer much larger bandwidth and potentially much higher data rates. Nevertheless, with the increase in frequency, the pathloss increases significantly, with the non-line-of-sight (nLoS) incurring attenuation levels that can dramatically reduce the quality of a wireless link. The use of directional antennas to counteract the increased pathloss is widely accepted. However, highly directional beams are prone to misalignment and a method to track the tracking object (TO) of the link with consistency, accuracy and low overhead is needed. To this end, the design of beam-tracking algorithms has been proposed. In this work, the main parameters that affect the reliability of beam-tracking are presented along with the challenges that beam-tracking algorithms need to address. Furthermore, the performance merits with respect to three reliability parameters are presented in the case of a simple beam-tracking algorithm.