Title :
Influence of laser phase on 400-Mbit/s coherent optical DPSK system
Author :
Kuo, C.-Y. ; Delavaux, J.-M.P. ; Ackerman, D.A. ; Tzeng, D.L.
Author_Institution :
AT&T Bell Labs., Allentown, PA, USA
fDate :
3/1/1989 12:00:00 AM
Abstract :
The influence of laser phase noise on a 400-Mb/s optical DPSK (differential phase-shift keying) system is experimentally investigated with linewidths ranging from 1.2 MHz to 8 MHz. This range corresponds to linewidth to bit rate ratios epsilon of 0.33-2%. The system performance with these nonzero linewidths is evaluated against a negligible linewidth performance baseline. The sensitivity degradation at a bit error rate of 10/sup -9/ increases from 1.8 to 7 dB as epsilon is increased from 0.33-1%. When epsilon is increased beyond 1%, bit error rate floors higher than 10/sup -9/ develop. These findings agree well with the existing theories and allow the generalization of these results to other bit rates, as well as establishing practical criteria for lasers to be used in DPSK systems.<>
Keywords :
noise; optical communication equipment; phase shift keying; 400 Mbit/s; differential phase-shift keying; laser phase noise; sensitivity degradation; Bit error rate; Bit rate; Degradation; Differential phase shift keying; Differential quadrature phase shift keying; Laser noise; Optical noise; Optical sensors; Phase noise; System performance;
Journal_Title :
Lightwave Technology, Journal of
