Multidimensional Modulation Formats for Coherent Optical Communication Systems
Licentiatavhandling, 2014

Coherent optical receivers have enabled the use of multilevel modulation formats with high spectral efficiencies and long transmission reaches. Traditionally, modulation formats utilizing the two dimensions spanned by the amplitude and the phase of the signal have been dominating. This thesis is devoted to novel modulation formats exploring the possibilities of modulation formats in higher dimensional signal spaces to find formats with a good tradeoff between spectral efficiency and sensitivity. The work included in this thesis can be divided into two parts, experimental and theoretical. The first part includes experimental demonstrations of several four- and eight-dimensional modulation formats where the sensitivity as well as the performance in terms of transmission reach is evaluated and compared to conventional modulation formats. 128-level set-partitioning QAM (128-SP-QAM) is demonstrated with 50 % increased transmission distance over polarization-multiplexed 16-ary quadrature amplitude modulation (PM-16QAM). Binary pulse position modulation in combination with QPSK (2PPM-QPSK) is shown to achieve 40 % increased transmission reach over PM-QPSK. Further, the eight-dimensional modulation format frequency and polarization switched QPSK (4FPS-QPSK) is shown to have 84 % increased transmission reach over polarization-multiplexed quadrature phase-shift keying (PM-QPSK) in a dual-carrier setup. The second part includes theoretical work where the spectral efficiency and asymptotic power efficiency is evaluated for modulation formats in high dimensional signal spaces. The high dimensionality is achieved by considering multidimensional position modulation, which is a generalization of pulse position modulation, in combination with QPSK and polarization-switched QPSK. The different dimensions can be achieved by time slots, polarizations, frequency slots, modes of multimode fibers or cores of a multicore fiber.

binary pulse position modulation QPSK

Fiber-optical communication

spectral efficiency

power efficiency

multidimensional position modulation.

16-ary quadrature amplitude modulation (16QAM)

quadrature phase shift keying (QPSK)

coherent detection

polarization-switched quadrature phase shift keying (PS-QPSK)

128-level set-partitioning QAM (128-SP-QAM)

Kollektorn MC2
Opponent: Dr. Mats Sköld


Tobias Eriksson

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

Frequency and polarization switched QPSK

39th European Conference and Exhibition on Optical Communication, ECOC 2013; London; United Kingdom; 22 September 2013 through 26 September 2013,; (2013)p. 816-818

Paper i proceeding

Comparison of 128-SP-QAM and PM-16QAM in long-haul WDM transmission

Optics Express,; Vol. 21(2013)p. 19269-19279

Artikel i vetenskaplig tidskrift

Long-Haul Transmission of PM-2PPM-QPSK at 42.8 Gbit/s

Optical Fiber Communications Conference (OFC) 2013, Anaheim,; (2013)

Paper i proceeding


Informations- och kommunikationsteknik





Technical report MC2 - Department of Microtechnology and Nanoscience, Chalmers University of Technology: 1652-0769

Kollektorn MC2

Opponent: Dr. Mats Sköld