New RFID (Radio-Frequency Identification) technologies aim to develop massive low-cost RF tags which not only return in a passive or semi-passive manner the IDs to a reader, but also identifies their locations from a distance >100m. Such functionality is essential for warehouses and stores. Since this also will increase the number of tags/devices in a given sensing area, multiple and secure access has to be realized. Secure localization and identification of any type of items is driving the RFID industry, allowing for new forms of wireless paying and user identification.