# Two-Dimensional Constellation Shaping in Fiber-Optic Communications
## 4 Concluding Remarks
In Proceedings of the Signal Processing in Photonic Communications (SPPCom), New Orleans, LA, USA, 24-27 July 2017; p. SpTu3E.2. * [PERSON] et al. (2018) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON] 159 Tbit/s C+ L band transmission over 1045 km 3-mode graded-index few-mode fiber. In Proceedings of the Optical Fiber Communication Conference (OFC), San Diego, CA, USA, 11-15 March 2018; p. Th4C-4. * [PERSON] et al. (2018) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON]; et al. Long-haul transmission over few-mode fibers with space-division multiplexing. _J. Lightw. Technol._**2018**, _36_, 1382-1388. [CrossRef]
* [PERSON] et al. (2014) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Analytical investigation on self-homodyne coherent system based on few-mode fiber. _Photon. Technol. Lett._**2014**, _26_, 74-77. [CrossRef]
* [PERSON] et al. (2016) [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON] Ultra-dense spatial-division-multiplexed optical fiber transmission over 6-mode 19-core fibers. _Opt. Express_**2016**, _24_, 10213-10231. [CrossRef] [PubMed]
* [PERSON] et al. (2018) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] [PERSON] Low transmission penalty dual-stage broadband discrete Raman amplifier. _Opt. Express_**2018**, _26_, 7091-7097. [CrossRef]
* [PERSON] et al. (2018) [PERSON]; [PERSON]; [PERSON]; [PERSON] Advanced MIMO signal processing techniques enabling long-haul dense SDM transmissions. _J. Lightw. Technol._**2018**, _36_, 336-348. [CrossRef]
* [PERSON] et al. (2015) [PERSON]; [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON] Generation, transmission, and detection of 4-D set-partitioning QAM signals. _J. Lightw. Technol._**2015**, _33_, 1445-1451. [CrossRef]
* [PERSON] (1990) [PERSON]; [PERSON] Non-equiprobable signaling on the Gaussian channel. _IEEE Trans. Inf. Theory_**1990**, _36_, 726-740. [CrossRef]
* [PERSON] (1992) [PERSON] Trellis shaping. _IEEE Trans. Inf. Theory_**1992**, _38_, 281-300. [CrossRef]
* [PERSON] and [PERSON] (1993) [PERSON]; [PERSON] Shaping multidimensional signal spaces. I. Optimum shaping, shell mapping. _IEEE Trans. Inf. Theory_**1993**, _39_, 1799-1808. [CrossRef]
* [PERSON] (1989) [PERSON]; [PERSON] Multidimensional constellations--Part I: Introduction, figures of merit, and generalized cross constellations. _IEEE J. Select. Areas Commun._**1989**, \(7\), 877-892. [CrossRef]
* [PERSON] (1989) [PERSON] Multidimensional constellations--Part II: Voronoi constellations. _IEEE J. Select. Areas Commun._**1989**, \(7\), 941-958. [CrossRef]
* [PERSON] et al. (2010) [PERSON]; [PERSON]; [PERSON]; [PERSON] Iterative polar quantization-based modulation to achieve channel capacity in ultrahigh-speed optical communication systems. _IEEE Photon. J._**2010**, \(2\), 593-599. [CrossRef]
* [PERSON] and [PERSON] (2018) [PERSON]; [PERSON] Design and comparison of advanced modulation formats based on generalized mutual information. _J. Lightw. Technol._**2018**, _36_, 416-423. [CrossRef]
* [PERSON] and [PERSON] (2018) [PERSON]; [PERSON] [PERSON] Hybrid probabilistic-geometric shaping in optical communication systems. In Proceedings of the 2018 IEEE Photonics Conference (IPC), Reston, VA, USA, 30 September-4 October 2018; pp. 1-2. * [PERSON] et al. (2017) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON] Coded modulation based on 56 APSK with hybrid shaping for high spectral efficiency transmission. In Proceedings of the 2017 European Conference on Optical Communication (ECOC), Gothenburg, Sweden, 17-21 September 2017; pp. 1-3. * [PERSON] et al. (2018) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Flex-rate transmission using hybrid probabilistic and geometric shaped 32 QAM.