Coded multipulse pulse-position modulation for free-space optical communications

—In this letter, we address two questions concerning the application of multipulse pulse-position modulation (MPPM) for free-space optical (FSO) communications: (1) under what condition would MPPM offer a notable advantage over conventional pulse-position modulation (PPM), and (2) what practical coding scheme should be used to realize that advantage. Focusing on bandwidth-efficient FSO transmission, we find decimated MPPM constellations which are suitable for combining with binary codes and offer significant gains in terms of constellationconstrained capacity over PPM under simultaneous peak-power, average-power, and bandwidth constraints. We then consider labeling design for the popular bit-interleaved coded modulation (BICM) and devise a new multilevel coding (MLC) architecture for MPPM, which we refer to as reduced-layer MLC (RLMLC). Considering the Poisson FSO channel model as a relevant example, we provide simulative evidence that RL-MLC MPPM with off-the-shelf low-density pa...

• Type: Journal
• Year: 2010
• Where: TCOM
• Authors: Trung Thanh Nguyen, Lutz H.-J. Lampe
• Keywords: Bandwidth-efficient Fso Transmission, Conventional Pulse-position Modulation, Pulse-position Modulation, TCOM 2010