Impact of Network Densification on the Performance of a Non-Public URLLC Factory Network

Abstract

Densification of the network deployment, for example by adding new sectors or sites within an existing mobile communication network, has traditionally been an efficient way to improve the system coverage and capacity. That will be the case even for the ultra-reliable low-latency communication (URLLC) services, but the overall situation and the feasibility of the different deployment options will depend on the characteristics of the URLLC service in question. URLLC services with relaxed latency requirements, allowing multiple transmission attempts, can tolerate a decent level of inter-cell interference while still being able to guarantee the desired quality-of-service for all users, which makes it possible to improve the URLLC service capacity by adding new gNodeBs with omnidirectional or directional antennas. However, when the URLLC services require extremely low latency that do not allow for retransmissions, the system performance becomes quite sensitive to the inter-cell interference, which means that in practice the gNodeBs should be equipped with beamformed antennas to reach high levels of URLLC service capacity. Finally, an active distributed antenna system could be an efficient way to secure good coverage throughout the desired service area.