Low-cost analog phase precoding is used to compensate chromatic dispersion (CD) in fibers with intensity modulation and direct detection (IM/DD). In contrast to conventional precoding with an in-phase and quadrature (IQ) Mach-Zehnder modulator (MZM), only a single additional phase modulator (PM) is required at the transmitter. Depending on the CD, the PM generates a periodic phase modulation that is modelled by a Fourier series and optimized via a mean squared error (MSE) cost criterion. Numerical results compare achievable information rates (AIRs) for 4- and 6-PAM. With the additional PM, energy gains of up to 3 dB are achieved for moderate fiber lengths.
@article{arxiv.2503.21282,
title = {Low-Cost Phase Precoding for Short-Reach Fiber Links with Direct Detection},
author = {Ulrike Höfler and Daniel Plabst and Norbert Hanik},
journal= {arXiv preprint arXiv:2503.21282},
year = {2025}
}