High-speed and low complexity carrier recovery for DP-QPSK transmission

This paper proposes a high speed and low complexity carrier recovery for 10 Gb/s dual-polarization quadrature phase shift keying (DP-QPSK). The Viterbi and Viterbi (V&V) algorithm is commonly used as a typical method for phase noise recovery. The V&V algorithm performs data dependency elimination by using complex multipliers that raise the value of the M-ary PSK signal to the power of M. However, the V&V algorithm may not be suitable for extremely high-speed carrier recovery because of the complicated complex multipliers. To achieve high speed and low complexity, we propose a new algorithm which performs data dependency elimination without using the complex multipliers. As a result, the proposed algorithm has lower hardware complexity and a higher clock rate compared with the V&V algorithm.