Techniques are described for wireless communication. A method for wireless communication at a user equipment (UE) includes receiving an instance of a discovery reference signal (DRS) on a beam over a shared radio frequency spectrum band; determining a public land mobile network identifier (PLMN ID) based at least in part on a time-frequency location of the instance of the DRS; and selectively performing a random access procedure based at least in part on the determined PLMN ID. A method for wireless communication at a base station includes transmitting an instance of a DRS on a beam over a shared radio frequency spectrum band; and transmitting a PLMN ID based at least in part on a time-frequency location of the DRS.