 operating bandwidths. Utilizing RF spectrum above 6 GHz for mobile broadband, low-latency mission-critical machine type communication, and low-energy massive machine type communication requires development of new radio interfaces or access technologies as well as substantial innovations in analog RF-integrated circuits and semiconductor technologies. In addition, carrier aggregation techniques are used to combine segments of spectrum that are not co- located within the same band to further improve peak data rates. 5G systems are required to support up to 400 MHz of contiguous bandwidth and to support a total bandwidth of up to 3.2 GHz via carrier aggregation beyond 6 GHz. Advanced driver assistance systems (ADAS) and autonomous vehicles are emerging trends in the automotive space. Together, they bring a number of benefits, including improved safety, reducing collision risks and road congestions, improved fuel economy, and higher productivity for the drivers. 5G wireless technologies supporting high-speed, low-latency vehicle-to-vehicle and vehicle-to-infrastructure communications are key enablers of ADAS and autonomous xxviii Introduction and Background vehicles. In addition, automotive industry is demanding richer infotainment options, which are adding more traffic bottlenecks to wireless networks. eCall is an initiative by the transportation safety regulatory bodies to provide immediate assistance to people involved in accidents. It is a subsystem of telematics systems being installed in vehicles. Implementation of eCall requires significant investment in infrastructure. In the case of a crash, it contacts the closest emergency center and forwards the GPS location of the crash site to the emergency center operators. eCall can be activated manually as well as automatically. It can be activated automatically, if the vehicle is involved in an accident and the airbags are inflated. As in the previous generations, improvements in radio access technologies, in the form of either evolutionary or revolutionary, have c