Carrier frequency and frames are synchronized in bursty data transmissions over unknown channels that cause inter-symbol interference. The synchronization procedure comprises two stages. The first stage performs a time-domain processing of samples to exploit a periodic signal repetition and to extract the coarse timing, the frequency offset and also to resolve frequency ambiguities. The second stage estimates the fine time offset of a received modulation signal. A coarse estimate of a frame start position of a received sequence of desired data samples may be improved by using the coarse timing estimate to generate frequency-domain received samples. A frequency-domain correlation is then determined between the frequency-domain received samples and noiseless samples. When using a fixed number of training samples, a "sandwich" preamble ("sandamble") is utilized to achieve greater efficiency than a conventional repetition preamble.
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