EQUALIZING A SIGNAL MODULATED USING A 5QAM MODULATION FORMAT

摘要

An optical system may include an optical transmitter or an optical receiver. The optical transmitter may include a laser to provide an input signal, a first digital signal processor (DSP) to receive a data signal, provide non-rotated and rotated symbols corresponding to the data signal, and provide digital signals corresponding to the non-rotated and the rotated symbols to cause one or more digital to analog converts to convert the digital signals to analog signals. The optical transmitter may further provide a modified 5 quadrature amplitude modulation (5QAM) signal based on the analog signals and the input signal. A constellation map of the modified 5QAM signal may include all constellation points of a 16QAM signal. The optical receiver may include a second DSP to receive components associated with the 5QAM signal, filter the components, reduce phase noise of the 5QAM signal, and provide data associated with the 5QAM signal.

主权项

1. An optical system, comprising:
an optical transmitter comprising:
a laser configured to provide an input signal;a digital signal processor (DSP) configured to:
receive a data signal,provide non-rotated symbols corresponding to components of the data signal,
the non-rotated symbols corresponding to first points in a constellation map,rotate the non-rotated symbols to provide rotated symbols,
the rotated symbols corresponding to second points in the constellation map that are rotated relative to the first points of the constellation map, andprovide digital signals corresponding to the non-rotated symbols and the rotated symbols to cause one or more digital to analog converts (DACs) to convert the digital signals to corresponding analog signals; andone or more modulators configured to receive the input signal and the analog signals and provide a modified 5 quadrature amplitude modulation (5QAM) output signal based on the input signal and the analog signals,
a constellation map of the modified 5QAM output signal including all constellation points of a 16QAM signal.