  We deliver a lattice study of $\rho$ resonance parameters with p-wave
$\pi\pi$ scattering phases, which are extracted by finite-size methods at one
center-of-mass frame and four moving frames for six MILC lattice ensembles with
pion masses ranging from $346$ to $ 176$ MeV. The effective range formula is
applied to describe the scattering phases as a function of the energy covering
the resonance region, this allows us to extract $\rho$ resonance parameters and
to investigate the quark-mass dependence. Lattice studies with three flavors of
the Asqtad-improved staggered fermions enable us to use the moving-wall source
technique on large lattice spatial dimensions ($L=64$) and small light $u/d$
quarks. Numerical computations are carried out at two lattice spacings, $a
\approx 0.12$ and $0.09$ fm.
