Abstract: A UE in a wireless communication system supporting a shared spectrum channel access is provided. The method comprises: determining a set of DSCH transmission windows based on a window periodicity, a window duration, and a window offset; determining a first set of SS/PBCH blocks within a DSCH transmission window of the set of DSCH transmission windows, wherein the first set of SS/PBCH blocks is QCLed; determining a second set of SS/PBCH blocks across at least two DSCH transmission windows being different DSCH windows of the set of DSCH transmission windows, wherein the second set of SS/PBCH blocks is QCLed; and receiving at least one SS/PBCH block that is located in the first set of SS/PBCH blocks or the second set of SS/PBCH blocks based on QCL information of the first set of SS/PBCH blocks or the second set of SS/PBCH blocks within the DSCH transmission window.

Abstract: A method and apparatus of transmitting a PPDU in a wireless communication system is provided. The method includes selecting a subchannel among a plurality of subchannels, wherein a PLCP preamble and a PLCP header in each PPDU are independently generated in each of the plurality of subchannels, and transmitting a PPDU in the selected subchannel.