Abstract
In this paper, we investigate experimentally and via simulation the pros
and cons of a narrow filter receiver for differential quadrature phase-shift
keying based on a single optical filter and eschewing the conventional
asymmetrical Mach–Zehnder interferometer structure. We quantify
the performance differences between the two receivers, allowing system
designers and operators to determine when the less complex narrow filter
receiver might be the appropriate choice. We numerically optimize the 3-dB
bandwidth and center frequency of the narrow filter and show it is more
robust to carrier frequency detuning than the conventional solution. We show
that the narrow filter receiver is more tolerant to chromatic dispersion
(CD) than the conventional one, and equally tolerant to first-order
polarization-mode dispersion. We show the impact of the 3-dB bandwidth on
the receiver performance when CD accumulates. Finally, we show via
experiments and simulations that the 3 dB advantage of the conventional
receiver vanishes when the nonlinear impairments are fiber nonlinearities;
comparing the two receivers at the optimum launch power for a 25$\,\times\,$80 km system, the difference in optical SNR margin is reduced to ${\sim} {\hbox {1.6}}$ dB. Experiments are conducted at 42 Gb/s using a commercially
available narrow filter for reception.
© 2009 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