Radio communication system using timeout control with flexible timeout interval setting

Abstract

In a radio communication system in which packet communications are carried out by setting up one or more connections between the radio base station and radio terminals, a radio base station or a radio terminal carries out the timeout control in which any packet that cannot be received completely through one connection within a timeout interval that is set in advance with respect to the one connection is regarded as lost, a change in a number of active connections that are currently carrying out communications with the radio base station is detected, and a new timeout interval is calculated and set with respect to each connection when the change in the number of active connections is detected.

1 - 19 . (canceled)  
   
   
       20 . A radio terminal device configured to communicate with a radio base station, comprising: 
 a receiver configured to receive packets through at least one of connections set up with the radio base station, said connections being assigned with connection IDs, respectively;    a timeout interval memory configured to store timeout intervals corresponding to connection IDs of connections currently carrying out communications with the radio base station;    a detector configured to detect a notice indicating to update timeout intervals, the notice being broadcasted from the radio base station when a change in a number of connections currently carrying out communications with the radio base station is detected; and    an update unit configured to update the timeout intervals stored in the timeout interval memory in response to the notice detected by the detector.    
   
   
       21 . The device according to  claim 20 , wherein the update unit calculates a new timeout interval for each connection to update the timeout intervals stored in the timeout interval memory in response to the detected notice.  
   
   
       22 . The device according to  claim 20 , wherein the update unit sets the timeout intervals stored in the timeout interval memory shorter or longer in response to the detected notice.  
   
   
       23 . The device according to  claim 20 , wherein the notice includes threshold data corresponding to timeout intervals calculated by the radio base station using the number of connections, and the update unit updates the timeout intervals stored in the timeout interval memory using the threshold data.  
   
   
       24 . The device according to  claim 20 , wherein the notice is broadcasted to all radio terminal devices that are carrying out communications with the radio base station.  
   
   
       25 . The device according to  claim 20 , further comprising: 
 a time counter configured to read current time;    a timeout timing memory configured to store next timeout data corresponding to the connection IDs; and    a timeout control unit configured to calculate next timeout data for each connection ID using the timeout intervals stored in the timeout interval memory and the current time, to store the next timeout data in the timeout timing memory, and to execute a timeout control in which a packet that is not received completely through one connection by the time the current time reaches the next timeout data with respect to the one connection is regarded as lost.