Technology for an eNodeB operable to perform physical random access channel (PRACH) transmissions in an unlicensed frequency band, in the context of 3GPP LTE eLAA, i.e. MuLTEfire, is disclosed. The eNodeB can identify a PRACH configuration being utilized by a MuLTEfire system that operates in an unlicensed spectrum. The PRACH configuration can define a number of continuous physical resource blocks (PRBs) in the unlicensed spectrum to be used for PRACH transmissions. The eNodeB can decode a PRACH transmission received from a user equipment (UE) in accordance with the PRACH configuration. The PRACH transmission can include a PRACH preamble that is transmitted using the number of continuous PRBs defined in the PRACH configuration. The eNB configures the performance of Clear Channel Assessment, CCA, before preamble transmission by the UE. In case the uplink transmission frame is configured with short PUCCH, sPUCCH, only a short CCA is configured. Otherwise, for example when the frame allows ePUCCH to be configured, CCA is followed by a self-deferring period.