DECISION-DIRECTED BURST-MODE CARRIER SYNCHRONIZATION TECHNIQUES

In burst-mode communication systems rapid carrier and clock synchronization is essential. In many practical applications an accurate phase reference can rapidly be obtained resulting in up to a 2-3 dB performance improvement over differentially coherent detection. This paper presents a decision-directed, digitally implemented carrier synchronizer for channels with both frequency and phase uncertainty. This combined algorithm and its derivatives are analyzed with respect to the achievable carrier acquisition time and the resulting bit error probability. For certain data rates (approximately 50 MSps or less) this algorithm can be implemented using CMOS gate array technology. As examples BPSK and QPSK modulation formats are studied herein and compared to their differentially coherent counterparts of DPSK and DQPSK.