  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.
