Techniques for tracking the motion of an RFID tag using signal strength information. A single antenna of an RFID reader may be used to take a sequence of readings from an RFID tag in motion. A signal strength indicator (e.g., received signal strength indicator (RSSI)) is determined for each reading. The sequence of RSSIs is then used to estimate a path of motion of the RFID tag and the direction of motion of the RFID tag along the path.