Communication method used for random access, terminal, and base station

Abstract

Embodiments of the present invention provide a communication method used for random access, including: receiving, by a terminal, random access preamble information sent by a base station; and before sending random access to the base station based on the random access preamble information, receiving, by the terminal, a random access response sent by the base station, where the random access response includes an uplink asynchronous hybrid automatic repeat request HARQ process identifier, and the uplink asynchronous HARQ process identifier is used by the terminal to send uplink data to the base station. Compared with the prior art, the communication method provided in the embodiments of the present invention can ensure to some extent that uplink data is transmitted timely and can effectively improve uplink data transmission reliability.

What is claimed is: 
     
         1 . A method, performing by a terminal, and the method comprising:
 instructing, by a media access control (MAC) layer, a physical layer to transmit a random access preamble;   receiving, by the MAC layer from the physical layer, an indication that indicates a transmission failure of the random access preamble; and   omitting, by the MAC layer based on the indication, a random access response.   
     
     
         2 . The method according to  claim 1 , wherein the omitting the random access response, comprises:
 skipping receiving the random access response.   
     
     
         3 . The method according to  claim 1 , wherein the omitting the random access response, comprises:
 skipping starting a timer of a random access response window.   
     
     
         4 . The method according to  claim 1 , wherein the omitting the random access response, comprises:
 skipping monitoring a physical downlink control channel (PDCCH) by using a random access radio network temporary identity (RA-RNTI).   
     
     
         5 . The method according to  claim 4 , the omitting the random access response, comprises:
 skipping monitoring the physical downlink control channel (PDCCH) of a primary and secondary cell (SpCell) by using the RA-RNTI, wherein the SpCell is a primary cell of a primary base station or a secondary base station in dual connectivity (DC), or the SpCell is a primary cell in carrier aggregation (CA).   
     
     
         6 . The method according to  claim 1 , further comprising:
 instructing, by the MAC layer in response to the failure of the random access preamble transmission, the physical layer to transmit a random access preamble again.   
     
     
         7 . The method according to  claim 1 , the transmission failure of the random access preamble comprises a listen before talk (LBT) failure for transmission of the random access preamble. 
     
     
         8 . The method according to  claim 1 , the instructing the physical layer to transmit a random access preamble, comprising:
 sending, by the MAC layer, information to the physical layer for transmission of the random access preamble, wherein the information comprises at least one of:   a physical random access channel (PRACH) resource, for transmitting the random access preamble;   a RA-RNTI, for receiving the random access response;   a random access preamble index, for generating a preamble sequence of the random access preamble based on a preamble root sequence and the random access preamble index; and   preamble transmit power.   
     
     
         9 . An apparatus, comprising a processor, configured to invoke a program stored in a memory, wherein the program, when executed by the processor, causes the apparatus to:
 instruct, by a media access control (MAC) layer, a physical layer to transmit a random access preamble;   receive, by the MAC layer from the physical layer, an indication that indicates a transmission failure of the random access preamble; and   omit, by the MAC layer based on the indication, a random access response.   
     
     
         10 . The apparatus according to  claim 9 , wherein the omitting the random access response, comprises:
 skipping receiving the random access response.   
     
     
         11 . The apparatus according to  claim 9 , wherein the omitting the random access response, comprises:
 skipping starting a timer of a random access response window.   
     
     
         12 . The apparatus according to  claim 9 , wherein the omitting the random access response, comprises:
 skipping monitoring a physical downlink control channel (PDCCH) by using a random access radio network temporary identity (RA-RNTI).   
     
     
         13 . The apparatus according to  claim 12 , the omitting the random access response, comprises:
 skipping monitoring the physical downlink control channel (PDCCH) of a primary and secondary cell (SpCell) by using the RA-RNTI, wherein the SpCell is a primary cell of a primary base station or a secondary base station in dual connectivity (DC), or the SpCell is a primary cell in carrier aggregation (CA) .   
     
     
         14 . The apparatus according to  claim 9 , wherein the program, when executed by the processor, causes the apparatus further to:
 instructing, by the MAC layer in response to the failure of the random access preamble transmission, the physical layer to transmit a random access preamble again.   
     
     
         15 . The apparatus according to  claim 9 , the transmission failure of the random access preamble comprises a listen before talk (LBT) failure for transmission of the random access preamble. 
     
     
         16 . The apparatus according to  claim 9 , the instructing the physical layer to transmit a random access preamble, comprising:
 sending, by the MAC layer, information to the physical layer for transmission of the random access preamble, wherein the information comprises at least one of:   a physical random access channel (PRACH) resource, for transmitting the random access preamble;   a RA-RNTI, for receiving the random access response;   a random access preamble index, for generating a preamble sequence of the random access preamble based on a preamble root sequence and the random access preamble index; and   preamble transmit power.   
     
     
         17 . A non-transitory computer-readable storage medium, comprising a program, wherein the program, when executed by a processor, causes the processor to:
 instruct, by a media access control (MAC) layer, a physical layer to transmit a random access preamble;   receive, by the MAC layer from the physical layer, an indication that indicates a transmission failure of the random access preamble; and   omit, by the MAC layer based on the indication, a random access response.