We describe how to calculate the Jones matrix transfer function of a fiber
if its principal states of polarization and its differential group delay as
functions of frequency are known. Using two counterexamples related to sec
ond-order polarization mode dispersion (PMD), we also show that a previous
method used for the same purpose induces overestimation of second-order PMD
effects by a factor of 2. Our new method is used to solve the problem for
both counterexamples. (C) 1999 Optical Society of America OCIS codes: 060.2
330, 060.4510, 060.2310, 060.2400, 060.2420, 260.5430.