  To ensure the high level of automation required in today's industrial
applications, next-generation wireless networks must enable real-time control
and automation of dynamic processes with the requirements of extreme
low-latency and ultra-reliable communications. In this paper, we provide a
performance assessment for the co-existence of a public enhanced mobile
broadband (eMBB) and a local non-public factory (URLLC) network and evaluate
the network conditions under which the stringent latency and reliability
requirements of factory automation applications are met. The evaluations
consider both an unsynchronized and a synchronized time division duplexing
(TDD) deployment between the networks, as well as scenarios both with and
without any macro eMBB traffic located inside the factory. The results show
that an unsynchronized deployment is possible if the isolation between the
networks is sufficiently high, either as a result of a separation distance,
wall loss or the use of separate frequencies for the networks. A synchronized
deployment will avoid the cross-link interference, but it will not resolve the
problems related to the closed access and the near-far interference. If the
factory contains eMBB traffic served by the overlaid macro cells, the
performance of both networks will suffer due to a high level of cross-link and
near-far interference. The problems related to the cross-link interference can
be resolved by synchronizing the networks, while the level of the near-far
interference can be reduced by allowing the eMBB users to be connected to base
stations located inside the factory. Finally, if an unsynchronized deployment
is desired, the factory should be deployed on an isolated frequency.
