Mobile communication system and communication method

Abstract

A wireless communication system comprises a first base station, a second base station, and a wireless terminal. The wireless terminal performs a handover from the first base station to the second base station. The first base station transmits information related to data volume of downlink data to the second base station, when the handover is performed. The second base station receives information related to the data volume.

Description

[0001]This application is the National Phase of PCT / JP2008 / 055274, filed Mar. 21, 2008, which is based upon and claims the benefit of the priority of Japanese patent application No. 2007-074554, filed on Mar. 22, 2007, the disclosure of which is incorporated herein in its entirety by reference thereto.FIELD OF THE INVENTION[0002]The present invention relates to a mobile communication system and base station thereof, and in particular to information relating to the number of packets (namely, data volume) at handover in the mobile communication system.BACKGROUND OF THE INVENTION [0003]A mobile communication system in 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) aims for an architecture as shown in FIG. 7. It is an object of this architecture to build a system that can realize shortening of transmission delay in a control plane and a user plane, and in which data transfer with higher throughput, for example, than existing systems can be realized.[0004]An operator...

AI Technical Summary

Benefits of technology

[0024]Consequently, it is an object of the present invention to solve the abovementioned problems, and to provide a mobile communication system (and in particular, a base station therefor) in which information on the number of packets (that is, data volume) counted up to now at a base station of a mobile source can be transferred to a base station of a mobile target even when a terminal performs a handover.

[0028]In this way, in the mobile communication system of the present invention, it is possible for information on the number of packets counted up until then by the eNode B to be transferred to the Target eNode B where the UE is moving to, even if the UE is undergoing handover between eNode Bs. That is, in the mobile communication system of the present invention, for example, after termination of UE communication, it becomes possible to accurately report the number of packets counted by the eNode B to the CN Node, and since the CN Node can report to a charging center, it becomes possible to have accurate charging.

[0029]Furthermore, in the mobile communication system of the present invention, even if the CN Node is switched due to a handover, by providing notification of information of the number of packets counted up until then from the switching source CN Node to a switching target, since it is possible to report information on the number of communicated packets of the UE to the charging center, it becomes possible to have accurate charging. Various aspects of the invention are described below.

[0034]In the present invention, by the abovementioned configuration and operation, an effect is obtained in which, even when a terminal performs a handover, it is possible for information on the number of packets counted up until then at a base station of a mobile source to be transferred to a base station of a mobile target.

Problems solved by technology

With regard to this LTE handover method, since a disconnect signal from a CN Node to a Source eNode B does not exist, there is a problem in that the amount counted by the Source eNode B cannot be reported to the CN Node.

This problem causes a further problem in that, since the Source eNode B cannot report the number of packets successfully received before a UE handover to the CN Node, it is not possible to accurately charge for the number of packets successfully received before the UE handover.

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