Patent ID: 8189533

Claim:
Method in a radio access network for managing a calculation of a destination time alignment value to be used by a user equipment in a destination cell after a handover, the radio access network comprising a source cell, the destination cell and the user equipment adapted to communicate with a source radio base station comprised in the source cell, the user equipment further being adapted to switch to communicate with a destination radio base station comprised in the destination cell after the handover, the user equipment further being adapted to perform a user equipment transmission, the source cell being adapted to transmit a first reference signal and the destination cell being adapted to transmit a second reference signal, the method comprising: obtaining a first information from the destination cell, the first information comprising a time difference between a point of time when the second reference signal is transmitted by the destination cell and a point of time when the destination cell receives the user equipment transmission, which time difference is denoted A; obtaining a second information comprising a time difference between a point of time when second reference signal is received by the user equipment and a point of time when the user equipment transmission is transmitted, which time difference is denoted C; and calculating the destination time alignment as a difference between the time difference A and the time difference C; and obtaining a third information from the user equipment, the third information comprising a time difference between a point of time when the first reference signal transmitted by the source cell is received by the user equipment and the point of time when the second reference signal transmitted by the destination cell is received by the user equipment, which time difference is denoted B.