  5G NR is touted to be an attractive candidate for tactical networks owing to
its versatility, scalability, and low cost. However, tactical networks need to
be stealthy, where an adversary is not able to detect or intercept the tactical
communication. In this paper, we investigate the stealthiness of 5G NR by
looking at the probability with which an adversary that monitors the downlink
synchronization signals can detect the presence of the network. We simulate a
single-cell single-eavesdropper scenario and evaluate the probability with
which the eavesdropper can detect the synchronization signal block when using
either a correlator or an energy detector. We show that this probability is
close to $ 100\% $ suggesting that 5G out-of-the-box is not suitable for a
tactical network. We then propose utilizing the uplink
channel-state-information to beamform the downlink synchronization-signals
towards the tactical user-equipment (UE) to lower the eavesdropper detection
probability while not compromising the performance of the legitimate tactical
UE.
