M. Stefanovic et al., EVALUATION OF OPTIMAL BANDWIDTH IN OPTICAL FSK SYSTEM INFLUENCED BY LASER PHASE NOISE, Journal of lightwave technology, 16(5), 1998, pp. 772-777
In this paper, an optical frequency shift keying (FSK) system with TFS
(two-filter structure), also known as dual-filter FSK, is observed in
the presence of laser phase noise. Sensitivity of the receiver is sho
wn as a function of intermediate frequency (IF) bandwidth and a bandwi
dth of the low-pass postdetection filter. It is shown that there is an
optimal pair of bandwidths which minimizes required sensitivity; a fe
w figures for different amounts of phase noise are given. The results
in this paper are based on truncated Taylor expansion method and a met
hod based on complex analysis is used to evaluate the integrals involv
ed.