Communication system, user equipment, base station, mobility management device, and gateway device

Abstract

In a communication system, an eNB and a UE transmit and receive a UE monitoring message for confirming the state of the UE in a predetermined UE monitoring period. For example, in UE monitoring periods, a UE monitoring procedure is performed, so that the UE transmits the UE monitoring message to the eNB. Upon receipt of the UE monitoring message, the eNB transmits delivery confirmation information to the UE. The UE monitoring period is set as, for example, a period shorter than a TAU period. This allows the UE monitoring process to confirm the state of the UE even if the TAU period is lengthened. The eNB may transmit the UE monitoring message to the UE.

1 . A communication system comprising a user equipment and a base station configured to perform radio communication with the communication device, wherein
 transmission/reception of data is performed between the user equipment and the base station during a random access procedure.   
     
     
         2 . The communication system according to  claim 1 ,
 wherein the random access procedure includes
 a first step where a random access preamble message is transmitted from the user equipment to the base station, 
 a second step where a random access response message is transmitted from the base station to the user equipment, 
 a third step where a scheduled transmission message is transmitted from the user equipment to the base station, and 
 a fourth step where a contention resolution message is transmitted from the base station to the user equipment, and 
   the transmission/reception of the data is performed using the scheduled transmission message in the third step.   
     
     
         3 . The communication system according to  claim 2 , wherein
 the scheduled transmission message in the third step contains establishment cause information, and   the establishment cause information contains information indicating that the data exists.   
     
     
         4 . The communication system according to  claim 1 , further comprising,
 in addition to the user equipment and the base station, a mobility management device configured to manage a movement of the user equipment and a gateway device configured to perform transmission/reception of data with the base station, wherein the communication system performs transmission/reception of data between the base station and the gateway device either using an interface between the base station and the gateway device or via the mobility management device, wherein,   when performing the transmission/reception of data between the base station and the gateway device via the mobility management device, the transmission/reception of data is performed during the random access procedure between the user equipment and the base station.   
     
     
         5 . A user equipment configured to perform radio communication with a base station, wherein,
 the user equipment is configured to perform transmission/reception of data with the base station during a random access procedure.   
     
     
         6 . A base station configured to perform radio communication with a user equipment, wherein,
 the base station is configured to perform transmission/reception of data with the user equipment during a random access procedure.   
     
     
         7 . A mobility management device in a communication system including a user equipment, a base station configured to perform radio communication with the user equipment, the mobility management device configured to manage a movement of the user equipment, and a gateway device configured to perform transmission/reception of data with the base station, wherein the communication system performs transmission/reception of data between the base station and the gateway device either using an interface between the base station and the gateway device or via the mobility management device, wherein
 when performing the transmission/reception of data between the base station and the gateway device via the mobility management device, the mobility management device is configured to perform the transmission/reception of data during the random access procedure between the user equipment and the base station.   
     
     
         8 . A gateway device in a communication system including a user equipment, a base station configured to perform radio communication with the user equipment, a mobility management device configured to manage a movement of the user equipment, and a gateway device configured to perform transmission/reception of data with the base station, wherein the communication system performs transmission/reception of data between the base station and the gateway device either using an interface between the base station and the gateway device or via the mobility management device, wherein
 when performing the transmission/reception of data between the base station and the gateway device via the mobility management device, the gateway device is configured to perform the transmission/reception of data during the random access procedure between the user equipment and the base station.