A User Equipment,UE, comprising: a wireless transceiver, configured to perform wireless transmission and reception to and from a cellular station; and a controller, configured to use first Physical Random Access Channel, PRACH, resources to perform a first PRACH transmission or retransmission, and switch to use second PRACH resources to perform a second PRACH retransmission subsequent to the first PRACH transmission or retransmission, wherein, when the first PRACH resources and the second PRACH resources are associated with the same downlink reference signal, the controller is further configured to increment a preamble transmission counter by one in response to the second PRACH retransmission, determine whether the first PRACH transmission or retransmission and the second PRACH retransmission are performed on the same beam or on different beams, increment a power ramping counter by one in response to the first PRACH transmission or retransmission and the second PRACH retransmission being performed on the same beam, and not increment the power ramping counter in response to the first PRACH transmission or retransmission and the second PRACH retransmission being performed on different beams, wherein, when the first PRACH resources and the second PRACH resources are associated with different downlink reference signals, the step of switching to use the second PRACH resources for the second PRACH retransmission is performed under at least one of the following conditions: a first measurement result of the downlink reference signal associated with the first PRACH resources is better than a second measurement result of the downlink reference signal associated with the second PRACH resources; a next occurrence of the second PRACH resources is closer to the current time than a next occurrence of the first PRACH resources; a first transmission power used for the first PRACH transmission or retransmission equals a maximum transmission power of the UE, while a total number of PRACH transmissions or retransmissions has not reached a maximum transmission number configured by the cellular station; and a Transmission Configuration Indication, TCI, state associated with a search space for monitoring a response to the first PRACH transmission or retransmission has been changed. a wireless transceiver, configured to perform wireless transmission and reception to and from a cellular station; and a controller, configured to use first Physical Random Access Channel, PRACH, resources to perform a first PRACH transmission or retransmission, and switch to use second PRACH resources to perform a second PRACH retransmission subsequent to the first PRACH transmission or retransmission, wherein, when the first PRACH resources and the second PRACH resources are associated with the same downlink reference signal, the controller is further configured to increment a preamble transmission counter by one in response to the second PRACH retransmission, determine whether the first PRACH transmission or retransmission and the second PRACH retransmission are performed on the same beam or on different beams, increment a power ramping counter by one in response to the first PRACH transmission or retransmission and the second PRACH retransmission being performed on the same beam, and not increment the power ramping counter in response to the first PRACH transmission or retransmission and the second PRACH retransmission being performed on different beams, wherein, when the first PRACH resources and the second PRACH resources are associated with different downlink reference signals, the step of switching to use the second PRACH resources for the second PRACH retransmission is performed under at least one of the following conditions: a first measurement result of the downlink reference signal associated with the first PRACH resources is better than a second measurement result of the downlink reference signal associated with the second PRACH resources; a next occurrence of the second PRACH resources is closer to the current time than a next occurrence of the first PRACH resources; a first transmission power used for the first PRACH transmission or retransmission equals a maximum transmission power of the UE, while a total number of PRACH transmissions or retransmissions has not reached a maximum transmission number configured by the cellular station; and a Transmission Configuration Indication, TCI, state associated with a search space for monitoring a response to the first PRACH transmission or retransmission has been changed. a first measurement result of the downlink reference signal associated with the first PRACH resources is better than a second measurement result of the downlink reference signal associated with the second PRACH resources; a next occurrence of the second PRACH resources is closer to the current time than a next occurrence of the first PRACH resources; a first transmission power used for the first PRACH transmission or retransmission equals a maximum transmission power of the UE, while a total number of PRACH transmissions or retransmissions has not reached a maximum transmission number configured by the cellular station; and a Transmission Configuration Indication, TCI, state associated with a search space for monitoring a response to the first PRACH transmission or retransmission has been changed.