free-space optical intensity channel. This channel is characterized by

inputs that are nonnegative (representing the transmitted optical

intensity) and by outputs that are corrupted by additive white

Gaussian noise (because in free space the disturbances arise from many

independent sources). Due to battery and safety reasons the inputs

are simultaneously constrained in both their average and peak

power. For a fixed ratio of the average power to the peak power the

difference between the upper and the lower bounds tends to zero as the

average power tends to infinity, and the ratio of the upper and lower

bounds tends to one as the average power tends to zero.

The case where only an average-power constraint is imposed on the

input is treated separately. In this case, the difference of the upper

and lower bound tends to 0 as the average power tends to infinity, and

their ratio tends to a constant as the power tends to zero.

-||- _|_ _|_ / __|__ Stefan M. Moser

[-] --__|__ /__\ /__ Senior Researcher & Lecturer, ETH Zurich, Switzerland

_|_ -- --|- _ / / Adj. Professor, National Chiao Tung University (NCTU), Taiwan

/ \ [] \| |_| / \/ Web: http://moser-isi.ethz.ch/

Last modified: Sat Oct 13 06:41:50 UTC+8 2007