论文信息 - A high-precision AFC circuit applied to 64QAM point-to-multipoint burst communications

A high-precision AFC circuit applied to 64QAM point-to-multipoint burst communications

We propose a novel automatic frequency control (AFC) circuit suitable for 64QAM point-to-multipoint (P-MP) burst communications. The proposed AFC circuit calculates the phase rotation during a sufficiently long time and adopts the variable-gain least mean squares (VLMS) algorithm to estimate the carrier frequency offset. The proposed AFC circuit is implemented with approximately 50 kgates. Its complexity level is much lower than that of the conventional one. Computer simulation and experimental results confirm achieving the frequency error of 5.3/spl times/10/sup -6/, and that it is sufficient for developing a 64QAM-40-Mbaud system.

Kazuji Watanabe | Yushi Shirato | Yosuke Akimoto

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