Five-level polybinary signaling for 10 Gbps data transmission systems

Abstract

This paper presents a revitalization effort towards exploiting multilevel polybinary signals for spectral efficient data links. Specifically, we present five level polybinary signaling for 10 Gbps signals. By proper coding to avoid error propagation and degeneracy of the bit error rate performance, a 10Gbps polybinary signal is successfully generated employing a 1.8 GHz Bessel filter with an electrical spectral efficiency of 5.5 bit/s/Hz. The experimental results show bit error rate performances below FEC level for transmission in singlemode and dispersion shifted fibers up to 20 km length.

Microstrip linear phase low pass filter based on defected ground structures for partial response modulation

“…The spectral efficiency of the modulated signals was 3.33 bit/Hz for duobinary and 4.89 bit/Hz for 5 levels PR, if we consider the 3-dB bandwidth. 6 We can notice that the filter performance was affected by the spurious response and the distortion introduced by the SMA connectors.…”

“…A simple duobinary transceiver scheme consists in applying a Bessel LPF to an electrical NRZ signal . Furthermore, this concept was extended for 5 and 7 levels PR modulations . Figure shows the eye diagrams of an NRZ signal and a duobinary, 5 and 7 levels PR signals at 10 Gbps and modulated by a Bessel LPF.…”

“…5 Furthermore, this concept was extended for 5 and 7 levels PR modulations. [6][7][8] Figure 1 shows the eye diagrams of an NRZ signal and a duobinary, 5 and 7 levels PR signals at 10 Gbps and modulated by a Bessel LPF. The choice of a Bessel 9,10 characteristic is motivated by the necessity of preserving a linear phase or maximally flat group delay, in order to avoid introducing distortion to the modulated PR signal.…”

“…These variations on conventional distributed feedback devices have many potential advantages such as higher single mode yield, lower threshold and higher slope efficiency. [6][7][8][9][10] Distributed feedback lasers have been extensively modeled. However, relatively little work has been on modeling of multisegment devices, including both ungrated regions and quarter-wave shifts with grated regions.…”

Microwave analog filter‐based modulators for partial response signals

“…A simple duobinary modulator design consists in applying an analog low‐pass filter (LPF) to a NRZ or a 4‐PAM signal. This concept, which we will address as analog PR, was extended to 5 and 7 levels PR modulations achieving state‐of‐the‐art results in terms of spectral efficiency for direct detection in optical systems. Analog PR can boost the spectral efficiency by only applying a precoding and having an analog LPF at the input of a standard NRZ or PAM modulator.…”