Abstract

Non-data-aided feedforward timing recovery is preferred to non-data-aided feedback timing recovery in digital receivers because it does not suffer delay in the loop. However, while feedback timing recovery with optimized predetection filter is not affected by self noise, in this paper it is pointed out for the first time that, even if an optimized predetection filter is adopted, feedforward timing recovery is. The paper proposes an approximation to the power spectral density of self noise that leads to analytical performance evaluation, the accuracy of the approximation being confirmed by simulation results. Also, a comparative study of feedforward and feedback timing recovery is presented. The result of the comparison is that, for signal-to-noise ratio lower than $50\,$ dB and realistic spectra of phase noise affecting the timing wave to be tracked, despite self noise, feedforward timing recovery outperforms feedback timing recovery.

© 2015 IEEE

Digital non-data-aided symbol synchronization in optical coherent intradyne reception

Sun Hyok Chang, Hwan Seok Chung, and Kwangjoon Kim
Opt. Express 16(19) 15097-15103 (2008)

All-Digital Timing Recovery and Adaptive Equalization for 112 Gbit∕s POLMUX-NRZ-DQPSK Optical Coherent Receivers

Xian Zhou, Xue Chen, Weiqing Zhou, Yangyang Fan, Hai Zhu, and Zhiyu Li
J. Opt. Commun. Netw. 2(11) 984-990 (2010)

Performance analysis of blind timing phase estimators for digital coherent receivers

Lingchen Huang, Dawei Wang, Alan Pak Tao Lau, Chao Lu, and Sailing He
Opt. Express 22(6) 6749-6763 (2014)

Time-domain low-complexity clock recovery for non-integer oversampled Nyquist signals with a small roll-off factor

Chengbo Li, Sheng Cui, Jingpeng Liu, Yanan Chen, Longquan Dai, Keji Zhou, and Ming Tang
Opt. Express 31(11) 18599-18612 (2023)

Parallel implementation of all-digital timing recovery for high-speed and real-time optical coherent receivers

Xian Zhou and Xue Chen
Opt. Express 19(10) 9282-9295 (2011)