Architecture Approaches For 5g Millimetre Wave Access Assisted By 5g Low-Band Using Multi-Connectivity

One of the key technology components envisioned for the delivery of extreme mobile broadband in 5G networks is the radio access using millimetre waves. However, using this technology, it is challenging to provide reliable and seamless data transmission to the users. Due to the propagation characteristics of millimetre waves, high interruption times may occur if line of sight is obstructed between the transmitter and the receiver. Therefore, we propagate that cellular deployment of systems using millimetre waves must be supported by the low-band (below 6 GHz) coverage and the 5G network should be able to provision multiple millimetre waves links for a user. For this purpose, we propose novel functionalities required for Multi-Connectivity in 5G. In line with our proposal, we present a set of different potential architectures for 5G radio access network and discuss their protocol and functional requirements. A qualitative assessment is carried out by comparing the required messages and the potential pros and cons for each architectural approach. Based on the evaluation, some recommendations are highlighted for the design of future 5G access network incorporating millimetre waves transmission.