Patent ID: 8644815
Filing Date: 2014-02-04
Classification: H04W

Abstract:
1. A mobile station communicating with a radio base station, the mobile station comprising: a synchronization state determination unit that determines a downlink synchronization state, based on a radio quality of a serving cell for the mobile station; a radio link failure state determination unit that determines whether or not a current state is a radio link failure state, based on the determination result; and a connection re-establishment unit that re-establishes a connection to the radio base station, when the radio link failure state determination unit determines that the current state is the radio link failure state, wherein when the synchronization state determination unit notifies that the downlink synchronization state is a non-synchronization state, when a first timer has expired, and when a second timer is being activated, the radio link failure state determination unit is configured to stop the second timer, and to determine that the current state is the radio link failure state; when the synchronization state determination unit notifies that the downlink synchronization state is a non-synchronization state, when the first timer is being activated, and when the second timer is being activated, the radio link failure state determination unit is configured to stop the second timer; and when the synchronization state determination unit notifies that the downlink synchronization state is a non-synchronization state, when the first timer is not being activated, the radio link failure state determination unit is configured to start the first timer.