This paper presents implementation and performance of QR Decomposition based Recursive Least-Squares (QRD-RLS) for interference mitigation in Wideband CDMA (WCDMA). The implementation is carried on CORSAEngine which is a new Software-Defined Radio (SDR) processor developed by NEC Corporation and highly optimized for MIMO-OFDM systems. It is shown how QRD-RLS can be mapped on its rectangular CORDIC-based reconfigurable systolic array, hence demonstrating its capability to process WCDMA. In addition, the performance of CORSAEngine is compared to that of other architectures and it is found to achieve at least 91% of the performance of dedicated hardware in terms of computational density.