On the Capacity of MISO Optical Intensity Channels With Per-Antenna Intensity Constraints

TL;DR

This paper analyzes the capacity of MISO optical intensity channels with per-antenna constraints, providing bounds and asymptotic behavior at different SNR levels, using advanced probabilistic tools.

Contribution

It introduces novel decomposition theorems and transforms MISO channels into single-input models with new constraints, advancing capacity analysis under intensity limitations.

Findings

Derived capacity bounds for MISO optical channels.

Established asymptotic capacity at high and low SNR.

Developed decomposition theorems for nonnegative random variables.

Abstract

This paper investigates the capacity of general multiple-input single-output (MISO) optical intensity channels (OICs) under per-antenna peak- and average-intensity constraints. We first consider the MISO equal-cost constrained OIC (EC-OIC), where, apart from the peak-intensity constraint, average intensities of inputs are equal to arbitrarily preassigned constants. The second model of our interest is the MISO bounded-cost constrained OIC (BC-OIC), where, as compared with the EC-OIC, average intensities of inputs are no larger than arbitrarily preassigned constants. By leveraging tools from quantile functions, stop-loss transform and convex ordering of nonnegative random variables, we prove two decomposition theorems for bounded and nonnegative random variables, based on which we equivalently transform both the EC-OIC and the BC-OIC into respective single-input single-output channels under a peak-intensity and several stop-loss mean constraints. Capacity lower and upper bounds for both channels are established, based on which the asymptotic capacity at high and low signal-to-noise-ratio are determined.