The wireless device receives random access (RA) configuration parameters of a bandwidth part (BWP) of a cell, indicating: one or more random access channel occasions (ROs), and a physical resource block (PRB) offset, with respect to a first PRB of the BWP, indicating a first RO of the one or more ROs. A frequency resource index of a second RO of the one or more ROs is determined based on a frequency resource index offset applied to the first RO. A preamble is transmitted via the second RO. A response to the preamble is received based on a random access (RA) identifier determined based on the frequency resource index of the second RO.