Open AccessEstimation and compensation of sample frequency offset in coherent optical OFDM systems
Author(s) -
Xingwen Yi,
Kun Qiu
Publication year - 2011
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.19.013503
Subject(s) - subcarrier , frequency offset , orthogonal frequency division multiplexing , offset (computer science) , phase compensation , phase noise , computer science , optics , compensation (psychology) , carrier frequency offset , sample (material) , electronic engineering , synchronization (alternating current) , channel (broadcasting) , telecommunications , physics , engineering , psychology , psychoanalysis , thermodynamics , programming language
Coherent optical OFDM systems employ DAC at the transmitters and ADC at the receivers. The sample frequencies of DAC and ADC in such systems need to be synchronized, especially in the context of high-speed transmissions. This paper presents a channel model including the effect of the sample frequency offset, which adds an additional phase shift proportional to the subcarrier index. The sample frequency offset monitoring and the compensation method are discussed and verified in experiment. It is expected that the synchronization can be achieved by feeding the monitoring result back to the receiver oscillator.