  In mm-wave networks, cell sizes are small due to high path and penetration
losses. Mobiles need to frequently switch softly from one cell to another to
preserve network connections and context. Each soft handover involves the
mobile performing directional neighbor cell search, tracking cell beam,
completing cell access request, and finally, context switching. The mobile must
independently discover cell beams, derive timing information, and maintain beam
alignment throughout the process to avoid packet loss and hard handover. We
propose Silent tracker which enables a mobile to reliably manage handover
events by maintaining an aligned beam until the successful handover completion.
It is entirely in-band beam mechanism that does not need any side information.
Experimental evaluations show that Silent Tracker maintains the mobile's
receive beam aligned to the potential target base station's transmit beam till
the successful conclusion of handover in three mobility scenarios: human walk,
device rotation, and 20 mph vehicular speed.
