User terminal

Abstract

In order to appropriately perform communication even when performing a random access procedure with fewer steps than the existing steps, an aspect of a user terminal according to the present disclosure includes a transmitting section that transmits a first UL signal including a preamble used for a random access and a second UL signal including a message, a receiving section that receives a response signal to the first UL signal and the second UL signal after the transmission of the second UL signal, and a control section that retransmits at least one of the first UL signal and the second UL signal based on a transmission failure of at least one of the first UL signal and the second UL signal.

1 . A user terminal, comprising:
 a transmitting section that transmits a first UL signal including a preamble used for a random access and a second UL signal including a message;   a receiving section that receives a response signal to the first UL signal and the second UL signal after the transmission of the second UL signal; and   a control section that retransmits at least one of the first UL signal and the second UL signal based on a transmission failure of at least one of the first UL signal and the second UL signal.   
     
     
         2 . The user terminal according to  claim 1 , wherein when the transmission of the first UL signal succeeds and the transmission of the second UL signal fails, the control section retransmits the second UL signal using an uplink shared channel scheduled by downlink control information. 
     
     
         3 . The user terminal according to  claim 2 , wherein a random access RNTI (RA-RNTI) or a temporary cell RNTI (TC-RNTI) is applied to a downlink control channel to which the downlink control information is transmitted. 
     
     
         4 . The user terminal according to  claim 1 , wherein the control section retransmits the first UL signal and the second UL signal when the transmission of the first UL signal fails. 
     
     
         5 . The user terminal according to  claim 1 , wherein the control section performs a random access procedure including a procedure from message 1 to message 4 when the transmission of the first UL signal and the second UL signal fails a given number of times. 
     
     
         6 . The user terminal according to  claim 5 , wherein the control section is configured to include the number of times of transmission of the first UL signal and the second UL signal in counting the maximum number of times of random access preamble transmission in the random access procedure including the procedure from the message 1 to the message 4. 
     
     
         7 . The user terminal according to  claim 2 , wherein the control section retransmits the first UL signal and the second UL signal when the transmission of the first UL signal fails. 
     
     
         8 . The user terminal according to  claim 3 , wherein the control section retransmits the first UL signal and the second UL signal when the transmission of the first UL signal fails. 
     
     
         9 . The user terminal according to  claim 2 , wherein the control section performs a random access procedure including a procedure from message 1 to message 4 when the transmission of the first UL signal and the second UL signal fails a given number of times. 
     
     
         10 . The user terminal according to  claim 3 , wherein the control section performs a random access procedure including a procedure from message 1 to message 4 when the transmission of the first UL signal and the second UL signal fails a given number of times. 
     
     
         11 . The user terminal according to  claim 4 , wherein the control section performs a random access procedure including a procedure from message 1 to message 4 when the transmission of the first UL signal and the second UL signal fails a given number of times.