An inventory management system includes an RFID reader, a multiplexing device operably connected to the RFID reader, and a plurality of shelving units. Each shelving unit has an outer boundary defined at least in part by RF blocking material. The inventory management system additionally includes a plurality of shelf antennas multiplexed to the RFID reader via the multiplexing device. At least one shelf antenna is routed within each shelving unit and tuned such that only RFID tags within the outer boundary of the shelving unit respond to an interrogation signal.