Proceedings ArticleDOI
A technique for measuring and optimizing modulator extinction ratio
David O. Caplan
- pp 335-336
TLDR
A new method for accurately measuring ER using the properties of average power limited (APL) amplifiers that does not require high-speed detection equipment is described.Abstract:
Summary form only given. As global communication systems rapidly expand and high-speed optical TDM and WDM networks continue to mature, the performance of optical modulators becomes increasingly important. Accurate methods of characterizing and optimizing key parameters, such as the extinction ratio, to levels exceeding 40 dB become necessary. The modulator extinction ratio (ER), defined as the power off-to-on ratio, impacts on communication performance in many ways. It determines the initial distance between logical zero and one power levels. Incomplete ER degrades sensitivity in optically preamplified links and leads to multiple interferometric cross talk, which adversely impacts both TDM and WDM systems. Furthermore, the ER limits the dynamic range of data-rates for variable duty-cycle (VDC) multi-rate optical communications. The author describes a new method for accurately measuring ER using the properties of average power limited (APL) amplifiers that does not require high-speed detection equipment.read more
Citations
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David O. Caplan,J. J. Carney,J. J. Fitzgerald,Igor D. Gaschits,Richard D. Kaminsky,G. Lund,Scott A. Hamilton,R. J. Magliocco,Robert J. Murphy,Hemonth G. Rao,N. W. Spellmeyer,J. P. Wang +11 more
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References
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Journal ArticleDOI
Experimental verification of a new model describing the influence of incomplete signal extinction ratio on the sensitivity degradation due to multiple interferometric crosstalk
TL;DR: In this paper, simple analytical relations for crosstalk induced power penalties are derived taking the signal extinction ratio into account and excellent agreement with 10-Gb/s experiments is obtained.
Proceedings ArticleDOI
High-sensitivity variable-rate transmit/receive architecture
TL;DR: DCE multi-rate communications from 51 Mbps through 1.244 Gbps using binary-pulse position modulation (PPM), this approach can easily be extended to higher bit-rates, other modulation formats, and is extremely well suited for M-ary PPM.
Journal ArticleDOI
Multiquantum well electroabsorption modulators for 80 Gbit/s OTDM systems
D.G. Moodie,Andrew D. Ellis,A.R. Thurlow,M.J. Harlow,I.F. Lealman,S.D. Perrin,L.J. Rivers,M.J. Robertson +7 more
TL;DR: In this paper, a fully packaged electroabsorption modulator is used to generate transform limited 4.1 ps pulses at a 20 GHz repetition rate and the feasibility of using this component for short pulse generation and demultiplexing in a four channel 80 Gbit/s OTDM system is discussed.
Journal ArticleDOI
Accurate optical extinction ratio measurements
P.O. Andersson,K. Akermark +1 more
TL;DR: In this article, the authors describe a method that increases the accuracy and repeatability of optical extinction ratio measurements from presently several percent to better than one percent, which is required when optimizing the performance of Gb/s optical transmitters using lasers or modulators for ultra low bit error rates.
Proceedings ArticleDOI
Extinction ratio effect for high-speed optical fiber transmissions
TL;DR: The interaction of the fiber dispersion, SPM, prechirp and extinction ratio is investigated and the optimisation of system performance is implemented for a 10 Gbit/s long distance unrepeatered unregenerate optical transmissions.