Patent ID: 10848287

Abstract:
A method and user equipment in a carrier frequency to perform contention based random access. The method includes receiving an indication from a network entity whether a cell in the carrier frequency supports a 2-step random access procedure. When the 2-step random access procedure is supported in the cell, a random access procedure is selected between the 2-step random access procedure and a 4-step random access procedure, wherein each of the 2-step random access procedure and the 4-step random access procedure includes one or more preambles, which are configured in the cell to be associated with one of the 2-step random access procedure or the 4-step random access procedures. A preamble is randomly selected and transmitted from the one or more preambles which are associated with the selected random access procedure, wherein the 2-step random access procedure includes a physical random access channel carrying preamble and a physical random access channel carrying data, and the 4-step random access procedure includes the physical random access channel carrying preamble, and wherein a time-frequency resource for the physical random access channel carrying data in the 2-step random access procedure is determined, based on the transmitted preamble. The physical random access channel carrying data is transmitted including a demodulation reference signal and one or more data symbols on the determined time-frequency resource.