A radio frequency identification (RFID) tag is embedded on a surgical instrument and a radio frequency identification (RFID) reader is provided on a surgical robot to allow identification of the attached surgical instrument. The RFID tag includes an RFID circuit assembly, a first pot core half, and a first toroidal wire coil that fits within the first pot core half and is electrically coupled to the RFID circuit assembly to modulate received radio frequency (RF) energy. The RFID reader includes an RFID transceiver circuit, a second pot core half, and a second toroidal wire coil that fits within the second pot core half and is electrically coupled to the transceiver circuit to transmit RF energy and receive modulated RF energy from the first wire coil only when the first pot core half is substantially aligned with and proximate to the second pot core half.