  Ultra-reliable low-latency Vehicle-to-Everything (V2X) communications are
needed to meet the extreme requirements of enhanced driving applications.
Millimeter-Wave (24.25-52.6 GHz) or sub-THz (>100 GHz) V2X communications are a
viable solution, provided that the highly collimated beams are kept aligned
during vehicles' maneuverings. In this work, we propose a sensor-assisted
dynamic Beamwidth and Power Control (BPC) system to counteract the detrimental
effect of vehicle dynamics, exploiting data collected by on-board inertial and
positioning sensors, mutually exchanged among vehicles over a parallel low-rate
link, e.g., 5G New Radio (NR) Frequency Range 1 (FR1). The proposed BPC
solution works on top of a sensor-aided Beam Alignment and Tracking (BAT)
system, overcoming the limitations of fixed-beamwidth systems and optimizing
the performance in challenging Vehicle-to-Vehicle (V2V) scenarios, even if
extensions to Vehicle-to-Infrastructure (V2I) use-cases are feasible. We
validate the sensor-assisted dynamic BPC on real trajectories and sensors' data
collected by a dedicated experimental campaign. The goal is to show the
advantages of the proposed BPC strategy in a high data-rate Line-Of-Sight (LOS)
V2V context, and to outline the requirements in terms of sensors' sampling time
and accuracy, along with the end-to-end latency on the control channel.
