Synchronizing communication between a mobile station and base station

A synchronizer 300 for use in a digital mobile communication system (100 fig.1), e.g. Terrestrial Trunked Radio (TETRA), to synchronize a communication between a mobile station and a base station. The synchronizer 300 includes a memory 303 to store for each of a plurality of mobile stations (104-109 fig.1) served by a base station (101 fig.1) a record comprising an identity of the mobile station together with a synchronization location in time of a previous synchronization of the mobile station. The synchronizer 300 also includes a processor 301 to retrieve the synchronization location from the record for a selected mobile station and to establish current synchronization with the mobile station using the retrieved location. The synchronization location may be a time, relative to a precise reference instant in time provided by a timer (205 fig.2), at which the most recent synchronization was found. The synchronization location may be measured in units of data symbols, or fractions of data symbols, displaced away from the precise instant in time.