A fast synchronizer for burst modems with simultaneous symbol timing and carrier phase estimations

In burst-mode data transmission used in GSM and IS-136, rapid acquisition of the symbol timing and the carrier phase from the observation of a short signal-segment is essential. Feedforward timing recovery is well suited for such transmissions due to its rapid acquisition characteristics. For personal mobile communications where low complexity and low power are the major requirements, it is desirable to sample the signal at the lowest possible rate and to have the synchronizer be as simple as possible. In this paper we propose a synchronizer for initial timing and carrier-phase estimation using preambles. The synchronizer needs just two samples per symbol period and it exhibits good performance, even for signals employing small excess bandwidth. These estimations can be obtained directly from the burst detector output. We also show that the synchronizer can be implemented very efficiently.