  We present an improved semi-analytic model for calculation of the broad
optical emission-line signatures from sub-parsec supermassive black hole
binaries (SBHBs) in circumbinary disks. The second-generation model improves
upon the treatment of radiative transfer by taking into account the effect of
the radiation driven accretion disk wind on the properties of the emission-line
profiles. Analysis of 42.5 million modeled emission-line profiles shows that
correlations between the profile properties and SBHB parameters identified in
the first-generation model are preserved, indicating that their diagnostic
power is not diminished. The profile shapes are a more sensitive measure of the
binary orbital separation and the degree of alignment of the black hole
mini-disks, and are less sensitive to the SBHB mass ratio and orbital
eccentricity. We also find that modeled profile shapes are more compatible with
the observed sample of SBHB candidates than with our control sample of regular
AGNs. Furthermore, if the observed sample of SBHBs is made up of genuine
binaries, it must include compact systems with comparable masses, and
misaligned mini-disks. We note that the model described in this paper can be
used to interpret the observed emission-line profiles once a sample of
confirmed SBHBs is available but cannot be used to prove that the observed SBHB
candidates are true binaries.
