Frequency synchronization bursts are detected for a radio communication system such as a GSM cellular telephone network using a two stage correlation process. A first unit performs a first set of correlations to identify receipt of the frequency synchronization burst. A preliminary identification is declared when the moving average of the first set of correlations, normalized for received power, exceeds a threshold value for a number of contiguous samples. After a preliminary identification is made, a second unit performs a second set of correlations to confirm the detection of the frequency synchronization burst. The second correlations are preferably also normalized and confirmation of detection is declared when the normalized moving average of the second stage correlation exceeds a threshold value for a number of contiguous samples.