POWER MOMENT DERIVATION FOR NOISY PHASE LIGHTWAVE SYSTEMS

The distribution law of the Brownian motion exponential functional: ep silon = \integral[0, 1] exp [jsquare-root2beta W(t)] dt\2, where {W(t) , t is-an-element-of R+} is a standard Brownian motion, modeling the l aser's phase noise, plays a key role in many of the proposed heterodyn e lightwave systems. The exact analytic derivation of these statistics appears to be, however, a formidable mathematical task. We present a closed form formula for the kth power moment Eepsilon(k) induced by th e unknown distribution law. The results are useful in assessing the pe rformance of noisy phase lightwave systems.