In this paper, we present a switched beamforming RFID reader and propose a convenient shopping system using it. The smart gate with the switched beamforming RFID reader(s) improves tag detection probability, tag false alarm probability, automatic detection functionality of shopping system compared to existing RFID based systems. The proposed system consists of a smart gate to read and verify the tags within cart, a check-out counter to approve customer purchase, and a central server to manage inventory & delivery and to analyze customer purchase trend. The proposed shopping system is more practical, convenient, and cost-effective to A/S than existing RFID shopping systems.