FREQUENCY OFFSET ESTIMATION METHOD AND DEVICE AND FRAME SYNCHRONIZATION SUBSYSTEM

摘要

The embodiments of the present invention provide a frequency offset estimation method and device and a frame synchronization subsystem. The method comprises: performing hard decisions on I-channel and Q-channel soft data corresponding to frequency offset compensation and phase offset compensation frame data in the same state of polarization, to obtain I-channel and Q-channel bit data; carrying out differential decoding of the I-channel and Q-channel bit data and pre-stored frame headers to obtain the differential-decoded I-channel and Q-channel bit data and pre-stored frame headers; according to the differential-decoded I-channel and Q-channel bit data and pre-stored frame headers, determining whether the frame headers in the differential-decoded I-channel and Q-channel bit data have inverted, and obtaining the result of the determination; according to the result, determining the phase offset corresponding to said frame data in the same state of polarization; taking said phase offset as the frequency offset fuzzy value to correct the frequency offset estimation and obtain a corrected frequency offset estimation. The embodiments of the present invention accomplish correction of a frequency offset estimation without requiring an increased optical transmission load.