Key Technologies, Modeling Approaches, and Challenges for Millimeter-Wave Vehicular Communications

Millimeter-wave communications have been recently proposed as a promising candidate to fulfill the connectivity requisites imposed over autonomous driving. The need for transmission capabilities of multiple gigabits per second for autonomous vehicles is the main driving factor for millimeter-wave technology. However, there are other paramount requirements, such as short delays, high reliability, security, and support for both unicast and broadcast communications, which must be carefully addressed before this technology becomes a reality. In this article we first review the state-of-the art modeling frameworks that are being considered for vehicular communications. Then we explore the key technologies that will enhance the suitability of millimeter-wave communications for autonomous driving, and we investigate the main challenges that need to be overcome. Finally, we envision that a combination of analog/ hybrid beamforming with a location-based beam search protocol, using full duplex radio and physical layer key generation, has the potential of fulfilling the requirements of autonomous driving technology.