RANDOM ACCESS METHOD AND DEVICE
FIG9 is a schematic diagram of detecting indication information by UE according to an embodiment of this application
For example, as shown in FIG9, when UE1 performs LBT, the UE1 may detect, on a subframe N by using CCA, whether the first carrier is idle. If it is determined that the carrier is idle, the UE1 may send a preamble on the carrier, and send indication information in reservation information (Reservation Signal). The indication information is used to notify another UE that a preamble is sent in a subframe N+1 and on a subsequent carrier. In this way, when detecting that the carrier is busy, UE2 may perform step 803, to further detect whether there is the indication information in the reservation signal.
schematic diagram
1002
detection unit
1004
receiving unit
1003
sending unit
10
terminal
1001
execution unit
['7. A terminal, comprising: an execution unit, configured to perform listen before talk LBT on a first carrier; a detection unit, configured to detect a first signal on the first carrier if it is determined, through the LBT, that the first carrier is in a busy state, wherein the first carrier comprises an unlicensed carrier, the first signal comprises a first preamble signal or indication information, and the indication information is used to indicate that the first carrier is used to send the first preamble signal; and a sending unit, configured to: if the first preamble signal or the indication information is detected, send a second preamble signal to a base station on the first carrier to attempt to access the base station.', '8. The terminal according to claim 7, further comprising a receiving unit, configured to receive a radio resource control RRC configuration message sent by the base station, wherein the RRC configuration message is used to instruct the terminal to detect the first preamble signal when the first carrier is in a busy state, or the RRC configuration message is used to instruct the terminal to detect the indication information when the first carrier is in a busy state.']