This paper compares two burst-mode clock and data recovery (BM-CDR) techniques suitable for bursty upstream data transmission, namely a gated voltage controlled oscillator (GVCO) and an oversampling clock phase alignment (CPA). Numeric models were deduced with timing jitter and duty cycle distortion (DCD) present in the received data. The performance of the two techniques are analyzed and compared especially in an optically amplified long-reach high-split PON (LR-PON) system. It is shown that an oversampling CPA exhibits a large DCD tolerance and better jitter rejection than a GVCO without line coding, resulting in high network efficiency while keeping fast bit synchronisation. This makes the oversampling CPA technique the best option for the proposed network.
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