Pion induced reactions provide unique opportunities for an unambiguous description of baryonic resonances and their coupling channels by means of a partial wave analysis. Using the secondary pion beam at SIS18, the two pion production in the second resonance region has been investigated to unravel the role of the $N(1520) frac{3}{2}^-$ resonance in the intermediate $rho$ production. Results on exclusive channels with one pion ($pi^{-}p$) and two pions ($pi^{+}pi^{-}n$, $pi^{0}pi^{-}p$) in the final state measured in the $pi^{-}-p$ reaction at four different pion beam momenta (0.650, 0.685, 0.733, and 0.786 GeV/c) are presented. The excitation function of the different partial waves and $Deltapi$, $Nsigma$ and $Nrho$ isobar configurations is obtained, using the Bonn-Gatchina partial wave analysis. The $N(1520) frac{3}{2}^-$ resonance is found to dominate the $Nrho$ final state with the branching ratio $BR=12.2 pm 1.9%$.
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