Aspects herein relate to wireless devices, circuits, and methods for determining a PRACH resource mapping comprising a starting symbol position within a reference slot, wherein the starting symbol position is determined based, at least in part, on a subcarrier spacing configuration of PRACH resources of a wireless network that a wireless device is operating on; and using the radio to transmit a RACH preamble and an associated RA-RNTI via the determined PRACH resource mapping. Further aspects herein relate to devices, circuits, and methods for using a modified RA-RNTI for transmission or reception of data over a wireless network, wherein the wireless network has a subcarrier spacing configuration of PRACH resources, wherein a size of the subcarrier spacing configuration of the PRACH resources causes out-of-range RA-RNTI values to be calculated using a legacy RA-RNTI equation in an unmodified form, wherein the range of permissible RA-RNTI values is from 0 to 216−1.