Method and apparatus for handling discontinuous reception (DRX) timer for data reception of unicast and multicast in a wireless communication system
In an example, a User Equipment (UE) receives and/or detects a transmission of data from a network. The transmission of the data is addressed to a Group Radio Network Temporary Identifier (G-RNTI) for a Hybrid Automatic Repeat Request (HARQ) process. In response to receiving and/or detecting the transmission of the data, the UE (i) starts a first HARQ Round Trip Time (RTT) timer associated with the G-RNTI for the HARQ process, and (ii) starts a second HARQ RTT timer associated with a Cell Radio Network Temporary Identifier (C-RNTI) for the HARQ process. The UE starts a multicast retransmission timer for the HARQ process in response to expiry of the first HARQ RTT timer. The UE starts a unicast retransmission timer for the HARQ process in response to expiry of the second HARQ RTT timer. The UE receives and/or detects a first retransmission of the DL data addressed to the G-RNTI for the HARQ process. In response to receiving and/or detecting the first retransmission of the data, the UE (i) stops the multicast retransmission timer, and (ii) stops the unicast retransmission timer.
1. A method of a User Equipment (UE), the method comprising:
at least one of receiving or detecting a transmission of data from a network, wherein the transmission of the data is addressed to a Group Radio Network Temporary Identifier (G-RNTI) for a Hybrid Automatic Repeat Request (HARQ) process;
in response to at least one of receiving or detecting the transmission of the data:
starting a first HARQ Round Trip Time (RTT) timer associated with the G-RNTI for the same HARQ process; and
starting a second HARQ RTT timer associated with a Cell Radio Network Temporary Identifier (C-RNTI) for the same HARQ process;
in response to expiry of the first HARQ RTT timer, starting a multicast retransmission timer for the same HARQ process;
in response to expiry of the second HARQ RTT timer, starting a unicast retransmission timer for the same HARQ process;
at least one of receiving or detecting a first retransmission of the data addressed to the G-RNTI for the same HARQ process; and
in response to at least one of receiving or detecting the first retransmission of the data for the same HARQ process:
stopping the multicast retransmission timer; and
stopping the unicast retransmission timer.
2. The method of claim 1 , comprising:
at least one of receiving or detecting a second retransmission of the data addressed to the C-RNTI for the same HARQ process; and
in response to at least one of receiving or detecting the second retransmission of the data:
stopping the multicast retransmission timer; and
stopping the unicast retransmission timer.
3. The method of claim 2 , comprising:
not starting the multicast retransmission timer in response to at least one of receiving or detecting the second retransmission of the data.
4. The method of claim 1 , comprising:
monitoring Physical Downlink Control Channel (PDCCH) when at least one of the multicast retransmission timer is running or the unicast retransmission timer is running.
5. The method of claim 1 , wherein:
the G-RNTI is used by the UE for receiving services from the network.
6. The method of claim 5 , wherein:
the G-RNTI is associated with a group of UEs, comprising the UE, that receive services from the network.
7. The method of claim 1 , comprising:
transmitting, to the network, Negative Acknowledgment (NACK) information for the same HARQ process if the data is not successfully decoded.
8. The method of claim 1 , wherein:
the network comprises a Next Generation NodeB (gNB).
9. The method of claim 1 , wherein:
the data comprises at least one of a transport block (TB) or a Medium Access Control Protocol Data Unit (MAC PDU).
10. A method of a User Equipment (UE), the method comprising:
at least one of receiving or detecting a transmission of data, associated with a Hybrid Automatic Repeat Request (HARQ) process, from a network;
in response to at least one of receiving or detecting the transmission of the data, at least one of:
starting a first HARQ Round Trip Time (RTT) timer associated with a Group Radio Network Temporary Identifier (G-RNTI) for the same HARQ process if the transmission of the data is addressed to the G-RNTI; or
starting a second HARQ RTT timer associated with a Cell Radio Network Temporary Identifier (C-RNTI) for the same HARQ process if the transmission of the data is addressed to the G-RNTI or the C-RNTI;
in response to expiry of the first HARQ RTT timer, starting a multicast retransmission timer for the same HARQ process;
in response to expiry of the second HARQ RTT timer, starting a unicast retransmission timer for the same HARQ process;
at least one of receiving or detecting a first retransmission of the data addressed to the G-RNTI or the C-RNTI for the same HARQ process; and
in response to at least one of receiving or detecting the first retransmission of the data for the same HARQ process:
stopping the multicast retransmission timer; and
stopping the unicast retransmission timer.
11. The method of claim 10 , comprising:
monitoring Physical Downlink Control Channel (PDCCH) when at least one of the multicast retransmission timer is running or the unicast retransmission timer is running.
12. The method of claim 10 , wherein:
the G-RNTI is used by the UE for receiving services from the network.
13. The method of claim 12 , wherein:
the G-RNTI is associated with a group of UEs, comprising the UE, that receive services from the network.
14. The method of claim 10 , comprising:
transmitting, to the network, Negative Acknowledgment (NACK) information for the same HARQ process if the data is not successfully decoded.
15. The method of claim 10 , wherein:
the network comprises a Next Generation NodeB (gNB).
16. The method of claim 10 , wherein:
the data comprises at least one of a transport block (TB) or a Medium Access Control Protocol Data Unit (MAC PDU).
17. A User Equipment (UE), comprising:
a control circuit;
a processor installed in the control circuit; and
a memory installed in the control circuit and operatively coupled to the processor, wherein the processor is configured to execute a program code stored in the memory to perform operations, the operations comprising:
at least one of receiving or detecting a transmission of data from a network, wherein the transmission of the data is addressed to a Group Radio Network Temporary Identifier (G-RNTI) for a Hybrid Automatic Repeat Request (HARQ) process;
in response to at least one of receiving or detecting the transmission of the data:
starting a first HARQ Round Trip Time (RTT) timer associated with the G-RNTI for the same HARQ process; and
starting a second HARQ RTT timer associated with a Cell Radio Network Temporary Identifier (C-RNTI) for the same HARQ process;
in response to expiry of the first HARQ RTT timer, starting a multicast retransmission timer for the same HARQ process;
in response to expiry of the second HARQ RTT timer, starting a unicast retransmission timer for the same HARQ process;
at least one of receiving or detecting a first retransmission of the data addressed to the C-RNTI for the same HARQ process; and
in response to at least one of receiving or detecting the first retransmission of the data for the same HARQ process:
stopping the multicast retransmission timer; and
stopping the unicast retransmission timer.
18. The UE of claim 17 , the operations comprising:
not starting the multicast retransmission timer in response to at least one of receiving or detecting the first retransmission of the data.
19. The UE of claim 17 , the operations comprising:
monitoring Physical Downlink Control Channel (PDCCH) when at least one of the multicast retransmission timer is running or the unicast retransmission timer is running.
20. The UE of claim 17 , wherein:
the G-RNTI is used by the UE for receiving services from the network; and
the G-RNTI is associated with a group of UEs, comprising the UE, that receive services from the network.