Practical RF fingerprints for Wireless Sensor Network authentication

We demonstrate empirically a physical layer authentication method that uses the physical attributes of OQPSK RF signals transmitted from IEEE 802.15.4 WSN nodes, collecting data with a USRP1 software-defined radio platform. We present simple training and classification algorithm alternatives and measure and analyze the performance of the overall combination. We improve classification performance using a simple method at the receiver that discards samples using preamble `PN chip' error information and estimates a phase offset between the transmitting node's RF clock and the receiver's sampling clock.