Various methods of control-less data transmission for NB-IoT/NR devices have been proposed to improve efficiency and system capacity in cellular networks. In a first embodiment, a PDCCH-less operation is performed between eNB and UE. UE will blindly decode some PDSCH subframes according to the parameters configured by higher layer. In a second embodiment, a PDCCH-lite operation is performed between eNB and UE. UE may use one PDCCH to schedule more than one subsequent PDSCH resources. In a third embodiment, an extremely compact DCI (E-DCI) format is used between eNB and UE. When the same assignment parameters are used by the eNB for the UE, DCI overhead may be reduced by E-DCI. In a fourth embodiment, direct data transmission in PDCCH is performed between eNB and UE. Data transmission is directly transmitted by PDCCH with a new DCI format.