Method and arrangement in a wireless communication system

Abstract

Method and arrangement in base station ( 110 ) for estimating the amount of data to be received from a terminal ( 120 ). The base station ( 110 ) and the terminal ( 120 ) are comprised within a wireless communication system ( 110 ). The terminal ( 120 ) comprises a buffer arranged to buffer frames comprising data. The method comprises determining ( 401 ) a service requested by the terminal ( 120 ), estimating ( 403 ) the arrival time of data to be received from the terminal ( 120 ), based on the determined service, and setting ( 404 ) a buffer estimate, comprising an estimation of the amount of data to be received, based on an estimated frame size for the determined service.

The invention claimed is:  
     
       1. Method in a base station for estimating an amount of data to be received from a terminal, wherein the base station and the terminal are within a wireless communication system, wherein the terminal comprises a terminal transmit buffer arranged to buffer frames comprising data, the method comprising:
 determining a service requested by the terminal, 
 estimating an arrival time of data to be received from the terminal, based on the determined service, 
 setting, by the base station, a terminal transmit buffer estimate based on the estimated arrival time, by estimating at the base station, an amount of data to be received by the terminal transmit buffer, based on an estimated frame size for the determined service, 
 receiving a buffer status report, the buffer status report comprising information related to the current state of the terminal transmit buffer in the terminal, and 
 updating the terminal transmit buffer estimate according to the buffer status report, 
 wherein the setting the terminal transmit buffer estimate is performed pre-emptively to the receiving the buffer status report. 
 
     
     
       2. Method according to  claim 1 , wherein estimating the arrival time of data is based on an estimation on the frame interval of the determined service. 
     
     
       3. Method according to  claim 1 , further comprising:
 receiving a scheduling request from the terminal, 
 wherein estimating the arrival time of data is based on the received scheduling request. 
 
     
     
       4. Method according to  claim 1 , further comprising:
 sending a grant to the terminal, wherein the grant allows the terminal to send an amount of data up to a size of the grant. 
 
     
     
       5. Method according to  claim 1 , comprising:
 receiving data from the terminal, 
 determining a size of the received data, and 
 setting a state based on the determined size of the received data, wherein the state is one of a first proactive buffer estimation state or a second passive state. 
 
     
     
       6. Method according to  claim 5 , further comprising:
 determining if the buffer estimate is set to zero, and 
 in response to determining that the buffer estimate is set to zero, setting the estimated arrival time to a transmission time of a scheduling request and the buffer estimate to the expected size of a state specific frame size based on the set state. 
 
     
     
       7. Method according to  claim 5 , further comprising:
 determining if the base station is in a first proactive buffer estimation state, and 
 in response to determining that the base station is in a first proactive buffer estimation state, increasing the buffer estimate by a size of a last received frame and setting a latest estimated arrival time to a current time, one frame interval after a last expected arrival time. 
 
     
     
       8. Method according to  claim 7 , wherein, if a Service Data Unit “SDU” is received from the terminal whose size is smaller than a threshold limit value, the base station is set into a passive state, otherwise the base station is set into the proactive buffer estimation state. 
     
     
       9. Method according to  claim 8 , wherein the threshold limit value is set to a value equal to, or larger than a size of a Silence Insertion Descriptor “SID” frame and smaller than, or equal to a size of a talk frame. 
     
     
       10. Method according to  claim 9 , wherein, in response to receiving two consecutive frames comprising only padding from the terminal, the base station is set into the passive state. 
     
     
       11. Arrangement in a base station for estimating an amount of data to be received from a terminal, wherein the base station and the terminal are within a wireless communication system, wherein the terminal comprises a buffer arranged to buffer frames comprising data, the arrangement comprising:
 a receiver, adapted to receive data from the terminal; and 
 a processor coupled to the receiver, wherein the processor is adapted to: 
 determine a service requested by the terminal, 
 estimate an arrival time of data to be received from the terminal, based on the frame interval of the determined service, 
 set a buffer estimate, wherein the buffer estimate comprises an estimation of the amount of the data to be received, based on an estimated frame size for the determined service, 
 receive a buffer status report, the buffer status report comprising information related to the current state of the terminal transmit buffer in the terminal, and 
 update the terminal transmit buffer estimate according to the buffer status report, 
 wherein the setting the terminal transmit buffer estimate is performed pre-emptively to the receiving the buffer status report. 
 
     
     
       12. The arrangement in a base station according to  claim 11 ,
 wherein the receiver is further adapted to receive a scheduling request from the terminal, and 
 wherein the estimate of the arrival time of data is based on the received scheduling request. 
 
     
     
       13. The arrangement in a base station according to  claim 11 ,
 wherein the processor is further adapted to send a grant to the terminal, wherein the grant allows the terminal to send an amount of data up to the size of the grant. 
 
     
     
       14. The arrangement in a base station according to  claim 11 , wherein the processor is further adapted to
 determine a size of the received data, and 
 set a state based on the determined size of the received data, wherein the state is one of a first proactive buffer estimation state or a second passive state. 
 
     
     
       15. The arrangement in a base station according to  claim 14 , wherein the processor is further adapted to
 determine if the buffer estimate is set to zero, and 
 in response to determining that the buffer estimate is set to zero, setting the estimated arrival time to a transmission time of a scheduling request and the buffer estimate to the expected size of a state specific frame size based on the set state. 
 
     
     
       16. The arrangement in a base station according to  claim 14 , wherein the processor is further adapted to
 determine if the base station is in a first proactive buffer estimation state, and 
 in response to determining that the base station is in a first proactive buffer estimation state, increasing the buffer estimate by a size of a last received frame and setting a latest estimated arrival time to a current time, one frame interval after a last expected arrival time. 
 
     
     
       17. Method according to  claim 1 ,
 wherein estimating the arrival time of data comprises estimating the arrival time of data to be received from the terminal in the future, and 
 wherein setting a terminal transmit buffer estimate comprises setting a terminal transmit buffer estimate based on the estimated arrival time in the future. 
 
     
     
       18. The arrangement in a base station according to  claim 11 ,
 wherein estimating the arrival time of data comprises estimating the arrival time of data to be received from the terminal in the future, and 
 wherein setting a terminal transmit buffer estimate comprises setting a terminal transmit buffer estimate based on the estimated arrival time in the future. 
 
     
     
       19. Method according to  claim 1 , wherein the size of the grant is based on estimating the amount of data to be received by the terminal transmit buffer. 
     
     
       20. The arrangement in a base station according to  claim 11 , wherein the size of the grant is based on estimating the amount of data to be received by the terminal transmit buffer.