Abstract
A novel scheme is proposed for all-optical multi-level phase quantization by mixing two lower-order harmonics, rather than mixing the signal with its conjugate
$(M\,{-}\,1)\text{th}$
harmonic, which is difficult to be generated but necessary for the traditional quantization method. The low-order harmonics used in the proposed scheme are determined as the conjugate
$(M/2\,{-}\,1)\text{th}$
and the
$(M/2\,{+}\,1)\text{th}$
harmonics for
$M=4n$
, or the conjugate
$(M/2-2)\text{th}$
and the
$(M/2+2)\text{th}$
harmonics for
$M=4n+2$
, or the conjugate
$[(M\,{-}\,1)/2]\text{th}$
and the
$[(M+1)/2]\text{th}$
harmonics for
$M=2n+1$
,
$n=1,2,3\ldots$
. The simulations show the effectiveness of the scheme for the eight- and nine-level all-optical phase quantization. Furthermore, the application of the scheme to the all-optical phase regeneration is validated. An improved method with two cascading stages is also proposed and validated to achieve a monotonic step-like phase–phase transfer characteristic for the optimized all-optical phase quantization. This proposed scheme provides a new way for multi-level phase quantization and multi-level phase shift keying regeneration to meet the ever increasing demand for the bandwidth in fiber-optic communication.
© 2018 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