Dynamic, untethered array nodes are frequency, phase, and time aligned/synchronized, and used to focus their transmissions of the same data coherently on a target or in the target's direction, using time reversal or directional beamforming. Information for alignment/synchronization may be sent from a master node of the array to other nodes, over non-RF links, such as optical and acoustic links. Some nodes may be connected directly to the master nodes, while other nodes may be connected to the master node through one or more transit nodes. A transit nodes may operate to (2) terminate the link when the alignment/synchronization information is intended for the node, and (2) pass through the alignment/synchronization information to another node without imposing its local clock properties on the passed through alignment/synchronization information. In this way, an end point node may be aligned/synchronized to the master node without a direct link between the two nodes.