Grant-free transmission method, network device, and terminal device

Abstract

This application discloses a grant-free transmission method, a network device, and a terminal device. The method includes: detecting, by a network device, a pilot sequence used by a terminal device for uplink transmission; determining, by the network device, a pilot sequence index of the pilot sequence based on the pilot sequence and a correspondence between the pilot sequence and the pilot sequence index; and sending, by the network device, information about a feedback result of the uplink transmission to the terminal device based on the pilot sequence index.

1 . A method comprising:
 detecting, by a network device, a pilot sequence in an uplink transmission sent by a terminal device;   determining, by the network device, a pilot sequence index of the pilot sequence based on a correspondence between the pilot sequence and the pilot sequence index; and   sending, by the network device, a bitmap to the terminal device, wherein a bit position in the bitmap corresponds to the pilot sequence index, and a value at the bit position indicates a feedback result of the uplink transmission.   
     
     
         2 . The method according to  claim 1 , wherein a quantity of bit positions in the bitmap is greater than or equal to a quantity of pilot sequences that are available for use for uplink transmissions. 
     
     
         3 . The method according to  claim 1 , wherein sending, by the network device, the bitmap to the terminal device comprises:
 sending, by the network device, downlink control information (DCI) carried on a physical downlink control channel to the terminal device, wherein the DCI comprises the bitmap; or   sending, by the network device, the bitmap carried on a physical downlink shared channel to the terminal device.   
     
     
         4 . The method according to  claim 1 , wherein the method further comprises:
 sending, by the network device, indication information to the terminal device, wherein the indication information instructs the terminal device to determine the feedback result based on the bitmap.   
     
     
         5 . A method comprising:
 determining, by a terminal device, a first pilot sequence index of a first pilot sequence based on a correspondence between the first pilot sequence and the first pilot sequence index, the first pilot sequence used in a first uplink transmission sent by the terminal device to a network device;   receiving, by the terminal device, a bitmap sent by the network device, wherein each bit position in the bitmap corresponds to a pilot sequence index, and a value at each bit position indicates a feedback result of an uplink transmission; and   determining, by the terminal device, a first feedback result of the first uplink transmission based on the first pilot sequence index and the bitmap.   
     
     
         6 . The method according to  claim 5 , wherein determining, by the terminal device, the first feedback result of the first uplink transmission based on the first pilot sequence index and the bitmap comprises:
 determining, by the terminal device based on the first pilot sequence index, a target bit position in the bitmap corresponding to the first pilot sequence index; and   determining, by the terminal device, the first feedback result based on a value at the target bit position, wherein the value at the target bit position indicates that the first feedback result is an acknowledgement (ACK) or a negative acknowledgement (NACK).   
     
     
         7 . The method according to  claim 5 , wherein receiving, by the terminal device, the bitmap sent by the network device comprises:
 receiving, by the terminal device, downlink control information (DCI) carried on a physical downlink control channel and sent by the network device, wherein the DCI comprises the bitmap; or   receiving, by the terminal device, the bitmap carried on a physical downlink shared channel and sent by the network device.   
     
     
         8 . The method according to  claim 5 , further comprising:
 receiving, by the terminal device, indication information sent by the network device, wherein the indication information instructs the terminal device to determine the feedback result based on the bitmap.   
     
     
         9 . A network device comprising:
 a non-transitory memory storage comprising instructions; and   one or more processors in communication with the memory storage, wherein the instructions, when executed by the one or more processors, cause the network device to:   detect a pilot sequence in an uplink transmission sent by a terminal device;   determine a pilot sequence index of the pilot sequence based on a correspondence between the pilot sequence and the pilot sequence index; and   send a bitmap to the terminal device, where a bit position in the bitmap corresponds to the pilot sequence index, and a value at the bit position indicates a feedback result of the uplink transmission.   
     
     
         10 . The network device according to  claim 9 , wherein a quantity of bit positions in the bitmap is greater than or equal to a quantity of pilot sequences that are available for use for uplink transmissions. 
     
     
         11 . The network device according to  claim 9 , wherein the instructions, when executed by the one or more processors, cause the network device further to:
 send downlink control information (DCI) carried on a physical downlink control channel to the terminal device, wherein the DCI comprises the bitmap; or   send the bitmap carried on a physical downlink shared channel to the terminal device.   
     
     
         12 . The network device according to  claim 9 , wherein the instructions, when executed by the one or more processors, cause the network device further to:
 send indication information to the terminal device, wherein the indication information instructs the terminal device to determine the feedback result based on the bitmap.   
     
     
         13 . A terminal device comprising:
 a non-transitory memory storage comprising instructions; and   one or more processors in communication with the memory storage, wherein the instructions, when executed by the one or more processors, cause the terminal device to:   determine, a first pilot sequence index of a first pilot sequence based on a correspondence between the first pilot sequence and the first pilot sequence index, the first pilot sequence used in a first uplink transmission sent by the terminal device to a network device;   receive a bitmap sent by the network device, wherein each bit position in the bitmap corresponds to a pilot sequence index, and a value at each bit position indicates a feedback result of an uplink transmission; and   determine a first feedback result of the first uplink transmission based on the first pilot sequence index and the bitmap.   
     
     
         14 . The terminal device according to  claim 13 , wherein the instructions, when executed by the one or more processors, cause the terminal device further to:
 determine, in the bitmap based on the first pilot sequence index, a target bit position corresponding to the first pilot sequence index; and   determine the first feedback result based on a value at the target bit position, wherein the value at the target bit position indicates that the first feedback result is an acknowledgement (ACK) or a negative acknowledgement (NACK).   
     
     
         15 . The terminal device according to  claim 13 , wherein the instructions, when executed by the one or more processors, cause the terminal device further to:
 receive downlink control information (DCI) carried on a physical downlink control channel and sent by the network device, wherein the DCI comprises the bitmap; or   receive the bitmap carried on a physical downlink shared channel and sent by the network device.   
     
     
         16 . The terminal device according to  claim 14 , wherein the instructions, when executed by the one or more processors, cause the terminal device further to:
 receive indication information sent by the network device, wherein the indication information instructs the terminal device to determine the feedback result based on the bitmap.