For example, although 10 Gbit/s systems typically utilize NRZ intensity modulation, it is necessary to employ more advanced modulation formats, such as
duobinary (DB) or phase shift keying (PSK) modulation to move to the rate of 40 Gbit/s and higher [5].
Fukuchi et al., "Characteristics of optical
duobinary signals in terabit/s capacity, high-spectral efficiency WDM systems," Journal of Lightwave Technology, vol.
To mitigate the effect of ICI and to overcome the transmitter complexity of MC-CDMA system,
duobinary coded receiver phase rotated conjugate cancellation (RPRCC) with pilot based CFO estimation is proposed in this work.
In the following equations we consider a postcursor channel with L = 1 and [d.sub.1] = 1 (i.e., a
duobinary channel).
The portfolio features products with different modulation formats, including NRZ, negative-chirp NRZ,
Duobinary and high dispersion tolerance, the company claims.
Bell Labs employed
Duobinary Signalling which uses three electrical (positive, negative and zero) signal levels and requires less bandwidth than NRZ signals and enabled the optical 107Gb/s serial data stream to be created.
TU5A-3: 10 Gb/s Electrical Backplane Transmission Using
Duobinary Signaling
A cost-effective solution was based on
duobinary modulation [3] and the adjustments of the RSOA's electro-optical (E/O) response to a 2.5 GHz Bessel filter.
Yano et al., "Feasibility study on over 1 bit/s/Hz high spectral efficiency WDM with optical
duobinary coding and polarization interleave multiplexing," in Proceedings of the Optical Fiber Communication Conference (OFC '97), pp.