Patent ID: 9503994
Filing Date: 2016-11-22
CPC Classification: H04L,H04W

Claim Text:
1. A method in a user equipment for adjusting a transmit timing of uplink transmissions to a network node in a telecommunications system, the user equipment configurable with more than one aggregated serving cells that are divided into one or more groups of serving cells based on a timing advance value of each of the aggregated serving cells, the one or more groups of serving cells each comprising a timing reference serving cell, wherein reception timing of a downlink transmission from a timing reference serving cell is used as a timing reference for the transmit timing of uplink transmissions for the serving cells in the group of serving cells comprising the timing reference serving cell, respectively, the method comprising: determining a change to a second timing reference serving cell in a group of serving cells, the second timing reference serving cell being different from a first timing reference serving cell currently being used as the timing reference serving cell for the group of serving cells; and applying an incremental adjustment of transmit timing of uplink transmissions for the serving cells in the group of serving cells with respect to a timing reference, the incremental adjustment based on reception timing of a downlink transmission from the second timing reference serving cell at the user equipment, wherein the incremental adjustment comprises two or more adjustments gradually applied in the incremental adjustment.