Patent ID: 9078194
Filing Date: 2015-07-07
Classification: H04W

Abstract:
1. A method of transmitting/receiving data by a mobile station with a first base station supporting a 1 st radio access technology and a second base station supporting a 2 nd radio access technology, in a radio access system supporting a multi-radio access technology (RAT), comprising: transmitting an indicator indicating the mobile station having a multi-RAT capability during network entry process with the first base station; if the indicator is received by the first base station, receiving, from the first base station, an information notifying that a multi-RAT capability negotiation process is performed after a completion of the network entry process; if the network entry process is an initial entry process to the first base station, performing a multi-RAT capability negotiation process with the first base station to exchange an information necessary for an additional access to the second base station; performing a scanning procedure on at least one second base station included in a coverage of the first base station based on the exchanged information received from the first base station by the multi-RAT capability negotiation process; performing an additional access procedure with a second base station of the at least one second base station; and transceiving the data simultaneously with the first base station and the second base station accessed by the additional access procedure, wherein if the network entry process is an re-entry process to the first base station prior to expiration of a predetermined timer, the multi-RAT capability negotiation process is omitted and the exchanged information is used for the re-entry process.