Adaptive Modulation and Coding for Free-Space Optical Channels

Free registration required

Executive Summary

Adaptive modulation and coding can provide robust and spectrally efficient transmission over terrestrial free-space optical channels. Three adaptive modulation schemes are considered in this paper: variable-rate variable-power adaptation, channel inversion, and truncated channel inversion schemes. It is shown that a simple channel inversion scheme performs comparable to a variablerate variable-power adaptation scheme in the weak turbulence regime but faces significant performance degradation in the strong turbulence regime. Authors further study adaptive coding based on large-girth quasi-cyclic Low-Density Parity-Check- (LDPC-) coded modulation.

  • Format: PDF
  • Size: 277.4 KB