Assessments on the performance of dual-frequency (13.6/35.5 GHz) precipitation radar (DPR) rain retrieval techniques are performed through simple vertical rain profiles synthesized with arbitrarily defined and disdrometer-measured raindrop size distribution (DSD) data. A DPR inversion technique (DPR-IT) with the estimates of differential attenuation (DA), which used to resolve the path-integrated attenuation (PIA) information instead of relying on surface reference or iterative methods, is considered mainly for the analysis. Preliminary simulation results show that the DPR-IT with DA constraint can work as an independent way to extract the DPR PIA information, hence, the DSD parameters, especially in the regions of moderate to strong rainfall rates.