A method performed by an uplink synchronization device comprised within a radio base station for enabling uplink synchronization of user equipment (30, 40, 50) present in a cell served by said radio base station, said method comprising: transmitting a first timing alignment command to said user equipment (30, 40, 50) triggering, based on said first timing alignment command, start of a timing alignment timer of the user equipment (30, 40, 50) with defined length of an associated time interval; characterised by: measuring uplink timing of uplink data received from said user equipment (30, 40, 50) during a measuring time window constituting a defined sub-interval of said time interval; determining, based on said measured uplink timing, a timing advance for said user equipment (30, 40, 50); co-scheduling transmission of a second timing alignment command comprising a notification of said timing advance together with a scheduled downlink data transmission to said user equipment (30, 40, 50) on a packet data shared channel, PDSCH, during a following scheduling time window constituting a defined sub-interval of said time interval and started upon an end of the measuring time window; and co-transmitting said second timing alignment command and said downlink data to said user equipment (30, 40, 50) on the PDSCH during said scheduling time window. transmitting a first timing alignment command to said user equipment (30, 40, 50) triggering, based on said first timing alignment command, start of a timing alignment timer of the user equipment (30, 40, 50) with defined length of an associated time interval; characterised by: measuring uplink timing of uplink data received from said user equipment (30, 40, 50) during a measuring time window constituting a defined sub-interval of said time interval; determining, based on said measured uplink timing, a timing advance for said user equipment (30, 40, 50); co-scheduling transmission of a second timing alignment command comprising a notification of said timing advance together with a scheduled downlink data transmission to said user equipment (30, 40, 50) on a packet data shared channel, PDSCH, during a following scheduling time window constituting a defined sub-interval of said time interval and started upon an end of the measuring time window; and co-transmitting said second timing alignment command and said downlink data to said user equipment (30, 40, 50) on the PDSCH during said scheduling time window. measuring uplink timing of uplink data received from said user equipment (30, 40, 50) during a measuring time window constituting a defined sub-interval of said time interval; determining, based on said measured uplink timing, a timing advance for said user equipment (30, 40, 50); co-scheduling transmission of a second timing alignment command comprising a notification of said timing advance together with a scheduled downlink data transmission to said user equipment (30, 40, 50) on a packet data shared channel, PDSCH, during a following scheduling time window constituting a defined sub-interval of said time interval and started upon an end of the measuring time window; and co-transmitting said second timing alignment command and said downlink data to said user equipment (30, 40, 50) on the PDSCH during said scheduling time window.