A base station may configure a first threshold indicating maximum numbers of blind decodes (BDs) and non-overlapping control channel elements (CCEs) for physical downlink control channel (PDCCH) candidates on a primary cell (PCell)/primary secondary cell (PSCell), and transmit, for a user equipment (UE), a configuration for PDCCH candidates in common search spaces (CSSs) or user-specific search spaces (USSs) on the PCell/PSCell and USSs on a secondary cell (SCell) for PDCCH scheduling data for the PCell/PSCell. The base station may transmit at least one PDCCH in PDCCH candidates. The UE may receive the configuration and receive the PDCCH by blindly decoding the PDCCH candidates in in at least one of the CSSs or the USSs configured on the PCell/PSCell and the USSs configured on the Scell. The USSs configured on the PCell/PSCell may support PDCCH overbooking.