Method and apparatus for transmission using preconfigured uplink resources in a wireless communication system

Abstract

A method and apparatus are disclosed from the perspective of a User Equipment (UE). In one embodiment, the method includes receiving, from a network node, a configuration of Preconfigured Uplink Resources (PUR), when the UE is in RRC_CONNECTED state, wherein the PUR is used for a transmission when the UE is in RRC_IDLE state. The method also includes determining to generate a first Radio Resource Control (RRC) message or a second RRC message for the transmission based on whether the transmission is to be transmitted using the PUR or not, wherein the first RRC message includes a UE identity and the second RRC message does not include the UE identity. The method further includes performing the transmission including the first RRC message or the second RRC message when the UE is in RRC_IDLE state.

1 . A method of a User Equipment (UE), comprising:
 receiving, from a network node, a configuration of Preconfigured Uplink Resources (PUR), when the UE is in RRC_CONNECTED state, wherein the PUR is used for a transmission when the UE is in RRC_IDLE state;   determining to generate a first Radio Resource Control (RRC) message or a second RRC message for the transmission based on whether the transmission is to be transmitted using the PUR or not, wherein the first RRC message includes a UE identity and the second RRC message does not include the UE identity; and   performing the transmission including the first RRC message or the second RRC message when the UE is in RRC_IDLE state.   
     
     
         2 . The method of  claim 1 , wherein the UE determines to generate the first RRC message or the second RRC message for the transmission based on whether the PUR is available or not. 
     
     
         3 . The method of  claim 1 , further comprising:
 generating the first RRC message if the transmission is not to be transmitted using the PUR.   
     
     
         4 . The method of  claim 1 , further comprising:
 generating the second RRC message if the transmission is to be transmitted using the PUR.   
     
     
         5 . The method of  claim 1 , further comprising:
 receiving, from the network node, a downlink message in response to the transmission, wherein the UE enters RRC_CONNECTED state in response to receiving the downlink message.   
     
     
         6 . The method of  claim 5 , further comprising:
 setting a Cell Radio Network Temporary Identifier (C-RNTI) to a value of a first RNTI in the configuration.   
     
     
         7 . The method of  claim 5 , further comprising:
 determining whether to set a Cell Radio Network Temporary Identifier (C-RNTI) to a value of a first RNTI in the configuration based on whether the downlink message includes a second RNTI or not.   
     
     
         8 . The method of  claim 1 , wherein the UE generates the first RRC message or the second RRC message when the UE wants to establish a RRC connection or when the UE initiates a RRC connection establishment procedure. 
     
     
         9 . The method of  claim 1 , wherein the UE generates the first RRC message or the second RRC message when the UE wants to resume a RRC connection or when the UE initiates a RRC connection resume procedure. 
     
     
         10 . The method of  claim 1 , wherein the first RRC message is a RRCEarlyDataRequest, RRCConnectionRequest, or RRCConnectionResumeRequest message. 
     
     
         11 . 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:
 receive, from a network node, a configuration of Preconfigured Uplink Resources (PUR), when the UE is in RRC_CONNECTED state, wherein the PUR is used for a transmission when the UE is in RRC_IDLE state; 
 determine to generate a first Radio Resource Control (RRC) message or a second RRC message for the transmission based on whether the transmission is to be transmitted using the PUR or not, wherein the first RRC message includes a UE identity and the second RRC message does not include the UE identity; and 
 perform the transmission including the first RRC message or the second RRC message when the UE is in RRC_IDLE state. 
   
     
     
         12 . The UE of  claim 11 , wherein the UE determines to generate the first RRC message or the second RRC message for the transmission based on whether the PUR is available or not. 
     
     
         13 . The UE of  claim 11 , wherein the processor is further configured to execute a program code stored in the memory to:
 generate the first RRC message if the transmission is not to be transmitted using the PUR.   
     
     
         14 . The UE of  claim 11 , wherein the processor is further configured to execute a program code stored in the memory to:
 generate the second RRC message if the transmission is to be transmitted using the PUR.   
     
     
         15 . The UE of  claim 11 , wherein the processor is further configured to execute a program code stored in the memory to:
 receiving, from the network node, a downlink message in response to the transmission, wherein the UE enters RRC_CONNECTED state in response to receiving the downlink message.   
     
     
         16 . The UE of  claim 15 , wherein the processor is further configured to execute a program code stored in the memory to:
 setting a Cell Radio Network Temporary Identifier (C-RNTI) to a value of a first RNTI in the configuration.   
     
     
         17 . The UE of  claim 15 , wherein the processor is further configured to execute a program code stored in the memory to:
 determine whether to set a Cell Radio Network Temporary Identifier (C-RNTI) to a value of a first RNTI in the configuration based on whether the downlink message includes a second RNTI or not.   
     
     
         18 . The UE of  claim 11 , wherein the UE generates the first RRC message or the second RRC message when the UE wants to establish a RRC connection or when the UE initiates a RRC connection establishment procedure. 
     
     
         19 . The UE of  claim 11 , wherein the UE generates the first RRC message or the second RRC message when the UE wants to resume a RRC connection or when the UE initiates a RRC connection resume procedure. 
     
     
         20 . The UE of  claim 11 , wherein the first RRC message is a RRCEarlyDataRequest, RRCConnectionRequest, or RRCConnectionResumeRequest message.