Techniques are disclosed for synchronizing frequency among a cluster of coordinated transmission points cooperating in a coherent joint transmission. In some embodiments, one transmission point is set (510) as a reference transmission point for a group of coordinated transmission points. Each of one or more other transmission points in the group receives (530) a specified downlink reference signal from the reference transmission point, measures (540) its frequency offset relative to the reference point, and compensates (550) the frequency offset in baseband processing or by a radio adjustment. Which transmission point acts as the reference transmission point is statically defined, in some embodiments, or dynamically configured, in others. Likewise, which time-frequency resources are used for the reference signal may be statically defined or dynamically configured. In some embodiments, information identifying the reference transmission point and/or specifying the radio resource locations and durations of the reference signal is distributed to the synchronizing transmission points.