Method for controlling retransmission of information using state variables in radio communication system

Abstract

A method for re-transmitting data or control information in a radio link control layer relates to determining whether re-transmission will be ended by comparing a number of transmission with a critical value when the transmission of data or control information has successively failed. The retransmission cycle is comprised of the steps in the order of transmitting information, checking the transmission failure with exit, and counting the transmission number with exit. Therefore, the present invention makes any transmission be checked and prevents wasting radio resource which can occur in re-transmitting data or control information in UMTS mobile communication system.

What is claimed is: 
     
       1. A method for transmitting information of a radio link control (RLC) layer in a radio communication system, the method comprising:
 transmitting, from a user equipment (UE) to a receiving device, data or control information of the RLC layer; 
 determining, at the UE, whether the transmission of the data or control information was unsuccessful; 
 only if the transmission was determined as being unsuccessful, comparing a number of transmissions of the data or control information with a value associated with a maximum number of transmissions; 
 only if the number of transmissions of the data or control information is less than the value associated with the maximum number of transmissions, repeating the transmitting, the determining, and the comparing operations; and 
 if the number of transmissions of the data or control information is equal to the value associated with the maximum number of transmission, providing an indication to an upper layer. 
 
     
     
       2. The method of  claim 1 , wherein the transmission of the data or control information is determined as being unsuccessful if a response comprising a negatively acknowledge (NACK) signal is received at the UE from the receiving device. 
     
     
       3. The method of  claim 1 , further comprising receiving, at the UE, a response from the receiving device, the response comprising a status Protocol Data Unit (PDU). 
     
     
       4. The method of  claim 1 , wherein the data or control information relates to an Acknowledged mode data (AMD). 
     
     
       5. The method of  claim 4 , wherein the data or control information of the RLC layer comprises at least one of user data unit, a Move Receiving Window (MRW) command or a reset command. 
     
     
       6. The method of  claim 5 , wherein the user data unit is an Acknowledged Mode Data (AMD) Protocol Data Unit (PDU). 
     
     
       7. The method of  claim 6 , wherein the number of transmissions of the data or the control information is associated with transmission of a sequence number of the user data unit. 
     
     
       8. The method of  claim 1 , wherein the data or control information of the RLC layer is retransmitted only once. 
     
     
       9. The method of  claim 1 , further comprising terminating the method if the transmission was determined as being successful. 
     
     
       10. The method according to  claim 1 , wherein the upper layer is a protocol layer that is above the RLC layer. 
     
     
       11. The method according to  claim 1 , wherein the indication comprises a report relating to transmission failure of the data or control information. 
     
     
       12. A method for transmitting information of a radio link control (RLC) layer in a radio communication system, the method comprising:
 comparing a number of transmissions of data or control information of the RLC layer with a value associated with a maximum number of transmissions; 
 only if the number of transmissions of the data or control information is less than the value associated with the maximum number of transmissions, transmitting, from a user equipment (UE) to a receiving device, the data or control information of the RLC layer and determining, at the UE, whether the transmission of the data or control information was unsuccessful; 
 only if the transmission was determined as being unsuccessful, repeating the comparing, the transmitting, and the determining operations; and 
 if the number of transmissions of the data or control information is equal to the value associated with the maximum number of transmission, providing an indication to an upper layer. 
 
     
     
       13. The method of  claim 12 , further comprising:
 initializing the number of transmissions of data or control information to a value of zero before comparing the number of transmissions of data or control information. 
 
     
     
       14. The method of  claim 12 , further comprising:
 incrementing the number of transmissions of data or control information after transmitting the data or control information and before determining whether the transmission was unsuccessful. 
 
     
     
       15. The method of  claim 12 , further comprising: incrementing the number of transmissions of data or control information after comparing the number of transmissions of data or control information and before transmitting the data or control information. 
     
     
       16. The method of  claim 12 , further comprising:
 only if the number of transmissions of the data or control information is equal to or greater than the value associated with the maximum number of transmissions, changing a setting for sending and receiving the data or control information of the RLC layer. 
 
     
     
       17. The method of  claim 12 , further comprising:
 terminating the method upon determining that the transmission was successful or when the number of transmissions of the data or control information is equal to or greater than the value associated with the maximum number of transmissions. 
 
     
     
       18. The method of  claim 12 , wherein the data or control information of the RLC layer comprises at least one of a user data unit, a Move Receiving Window (MRW) command or a reset command. 
     
     
       19. The method of  claim 12 , wherein the number of transmissions of the data or control information is associated with transmission of at least one of a user data unit, a Move Receiving Window (MRW) command or a reset command. 
     
     
       20. The method of  claim 12 , wherein the value associated with the maximum number of transmissions is associated with transmission of at least one of a user data unit, a Move Receiving Window (MRW) command or a reset command. 
     
     
       21. The method according to  claim 12 , wherein the upper layer is a protocol layer that is above the RLC layer. 
     
     
       22. The method according to  claim 12 , wherein the indication comprises a report relating to transmission failure of the data or control information. 
     
     
       23. A user equipment (UE) for transmitting information in a radio communication system, the UE comprising:
 a radio link control (RLC) layer; and 
 a processor configured to:
 transmit data or control information of the RLC layer to a receiving device; 
 determine whether the transmission of the data or control information was unsuccessful; 
 compare, only if the transmission was determined as being unsuccessful, a number of transmissions of the data or control information with a value associated with a maximum number of transmissions; 
 repeat, only if the number of transmissions of the data or control information is less than the value associated with the maximum number of transmissions, the transmit, the determine, and the compare operations; and 
 if the number of transmission of the data or control information is equal to the value associated with the maximum number of transmission, provide an indication to an upper layer. 
 
 
     
     
       24. The UE according to  claim 23 , wherein the upper layer is a protocol layer that is above the RLC layer. 
     
     
       25. The UE according to  claim 23 , wherein the indication comprises a report relating to transmission failure of the data or control information. 
     
     
       26. A method for transmitting information in a radio communication system, the method comprising:
 transmitting, from a user equipment (UE) to a receiving device, data, wherein the data is a data type protocol data unit (PDU);   determining, at the UE, whether an acknowledgement (ACK) related to the data is received at the UE before a timer is expired;   if the ACK is not received before the timer is expired, increasing a state variable related to a number of transmissions of the data, wherein the increasing the state variable occurs after the determining;   only if the ACK is not received before the timer is expired, comparing the state variable with a value associated with a maximum number of transmissions;   only if the state variable related to the number of transmissions of the data is less than the value associated with the maximum number of transmissions, repeating the transmitting, the determining, the increasing, and the comparing operations; and   if the state variable related to the number of transmissions of the data is equal to the value associated with the maximum number of transmissions, transmitting control information related to a Move Receiving Window (MRW) instruction to move a receiving window.