Optical signal transmission device and method based on digital predistortion in symbol domain
An optical signal transmission device and method based on digital predistortion in a symbol domain is provided. The optical signal transmission device includes: a memory; and a processor coupled to the memory to control execution of a process to: perform digital predistortion processing on a symbol sequence of a signal to be transmitted to obtain a digital predistortion processed signal; perform short-pulse shaping processing on the digital predistortion processed signal to obtain a short-pulse shaping processed signal, wherein a memory length introduced by the short-pulse shaping processing is less than or equal to a memory length of the optical transmitter; and generate and transmit an optical signal based on the short-pulse shaping processed signal.
1 . An optical signal transmission device based on digital predistortion in a symbol domain, the optical signal transmission device being arrangeable in an optical transmitter, the optical signal transmission device comprising:
a memory; and
a digital processor coupled to the memory to control execution of a process to:
perform digital predistortion processing on a symbol sequence of a signal to be transmitted to obtain a digital predistortion processed signal;
perform short-pulse shaping processing on the digital predistortion processed signal to obtain a digital short-pulse shaping processed signal, a trailing attenuation of the digital short-pulse shaping processed signal pulse being fast and a swing of the digital short-pulse shaping processed signal pulse being small, a memory length introduced by the digital short-pulse shaping processing is less than or equal to a memory length of the optical transmitter; and
generate and transmit an optical signal based on the digital short-pulse shaping processed signal.
2 . The optical signal transmission device according to claim 1 , wherein the digital processor performs short-pulse shaping processing on the digital predistortion processed signal in a digital domain to obtain a short-pulse shaping processed digital signal.
3 . The optical signal transmission device according to claim 2 , wherein the digital processor performs short-pulse shaping processing on the digital predistortion processed signal by using a finite impulse response digital filter.
4 . The optical signal transmission device according to claim 3 , wherein the digital processor:
converts the short-pulse shaped signal into an analog electrical signal by using a digital-to-analog converter;
amplifies the analog electrical signal by using a driver amplifier to obtain an amplified analog electrical signal; and
loads the amplified analog electrical signal onto an optical carrier by using an optical modulator to generate and transmit the optical signal.
5 . The optical signal transmission device according to claim 1 , wherein the digital processor:
performs filtering processing on the generated optical signal by using an optical filter to reduce a spectral bandwidth occupied by the optical signal, to transmit the optical signal with a reduced spectral bandwidth.
6 . The optical signal transmission device according to claim 1 , wherein the digital processor:
performs power amplifying processing on the generated optical signal by using an optical amplifier; and
performs filtering processing on a power amplified optical signal by using an optical filter to reduce a spectral bandwidth occupied by the optical signal, to transmit the optical signal with a reduced spectral bandwidth.
7 . An optical transmitter, which comprises the optical signal transmission device according to claim 1 .
8 . The optical signal transmission device according to claim 1 , wherein the digital processor performs short-pulse shaping processing on the digital predistortion processed signal to obtain the short-pulse shaping processed signal, a filter used in the short-pulse shaping has a larger roll-off coefficient than a filter used in long-pulse shaping.
9 . An optical signal transmission device based on digital predistortion in a symbol domain, the optical signal transmission device being arrangeable in an optical transmitter, the optical signal transmission device comprising:
a memory; and
a processor coupled to the memory to control execution of a process to:
perform digital predistortion processing on a symbol sequence of a signal to be transmitted to obtain a digital predistortion processed signal;
perform short-pulse shaping processing on the digital predistortion processed signal to obtain a short-pulse shaping processed signal, a trailing attenuation of the short-pulse shaping processed signal pulse being fast and a swing of the short-pulse shaping processed signal pulse being small, a memory length introduced by the short-pulse shaping processing is less than or equal to a memory length of the optical transmitter, a filter used in the short-pulse shaping has a larger roll-off coefficient than a filter used in long-pulse shaping; and
generate an optical signal based on the short-pulse shaping processed signal;
perform filtering processing on the generated optical signal by using an optical filter to reduce a spectral bandwidth occupied by the optical signal, to transmit the optical signal with a reduced spectral bandwidth.