Improved alignment of synchronization in an LTE system in case of random access preamble conflict

摘要

A method (500) for use in a user terminal (120, 130) in a cellular communication system (100), method according to which the user terminal applies (505) a first synchronization advance value (TTA1) to its transmissions to a controller node (140), and method according to which the user terminal (120, 130) requests (510) communication with the controller node (140) in a dispute-based procedure by transmitting a random access preamble ( MSG 1), and, in response (515), the user terminal receives from the controller node a random access response (MSG 2) together with (520) a second synchronization advance value (TTA2), characterized by the method (500 ) because the user terminal (120, 130) uses (523, 524) the first synchronization advance value if the user terminal loses the dispute-based procedure; that is, if the controller node subsequently continues the communication initiated with another user terminal.