Abstract
Nyquist pulse shaping can be used to increase the spectral efficiency
(SE) by narrowing the signal spectrum without introducing intersymbol interference
in a wavelength-division-multiplexed (WDM) system. In this paper, we investigate
the complexity and performance of pulse shaping at the transmitter side using
digital finite-impulse-response (FIR) or frequency-domain-equalization (FDE)
filters to increase the SE in a polarization-division-multiplexed quadrature-phase-shift-keyed
WDM system. Simulation results show that FIR filters with 17 taps allow for
a reduction in channel spacing to 1.1 times the symbol rate within a 1 dB
penalty. The root-raised-cosine spectrum shape has better performances than
the raised-cosine spectrum shape with that channel spacing. An FDE filter
with a fast Fourier transform size of 64 and an overlap length of 8 points
performs slightly better than a 17-tap FIR filter.
© 2012 IEEE
PDF Article
More Like This
Cited By
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
Contact your librarian or system administrator
or
Login to access Optica Member Subscription