Capacity Bounds for Power- and Band-Limited Wireless Infrared Channels Corrupted by Gaussian Noise

摘要

This paper finds asymptotically exact upper and lower bounds on the channelcapacity of power and band-limited optical intensity channels corrupted by whiteGaussian noise. This work differs from the oft investigated case of the Poissonphoton counting channel in that not only are rectangular pulse amplitude schemesconsidered, but results for more general time-disjoint intensity modulation schemesare presented. The role of bandwidth is expressed by way of the effective dimensionof the set of signals. The bounds show that at high optical signal-to-noise ratios theuse of bandwidth efficient pulse sets is essential to achieve high spectral efficiencies.This result can be considered as an extension of previous work on photon countingchannels which more closely model low optical intensity channels.