A method for a multicast service is provided. In this example, the method includes receiving, by a user equipment (UE), a control format including a resource allocation field from a base station (BS), the resource allocation field indicating a starting resource block (RB) index and an RB range, obtaining a set of RBs allocated for a multicast physical downlink shared channel (PDSCH) or physical uplink shared channel (PUSCH) based on a starting RB location and the RB range; wherein the starting RB location is associated with the stating RB index and at least one of a reference RB location or an assigned sub-band; and transmitting or receiving, by the UE, data over at least one RB of the set of RBs allocated for the multicast PDSCH or PUSCH.