RF-DNA Fingerprinting for Airport WiMax Communications Security

Wireless communication security is addressed using device-specific RF-DNA fingerprints in a localized regional air monitor. The targeted application includes IEEE 802.16 WiMax-based airport communications such as being proposed by the Euro control and FAA organizations-concept validation is currently underway using the Aeronautical Mobile Airport Communications System (AeroMACS) network. Security enhancement via RF-DNA fingerprinting is motivated by earlier RF-DNA work using GMSK-based intra-cellular GSM signals and OFDM-based 802.11a peer-to-peer WiFi signals. The commonality that WiMax shares with these two existing communication systems, i.e., the cellular control structure of GSM and the multi-carrier OFDM modulation of 802.11a, suggests that RF-DNA fingerprinting may be effective for WiMax device discrimination. This is important given that WiMax shares some common features that may prove detrimental, to include bit-level authentication, privacy, and security mechanisms. It is reasonable to assume that these bit-level mechanisms will come under attack as ``hackers´´ apply lessons learned from their previous successes. The contributions of this paper include: 1) the introduction of a Spectral Domain (SD) RF-DNA fingerprinting technique to augment previous Time Domain (TD) and Wavelet Domain (WD) techniques, and 2) a first look at AeroMACS physical waveform features and the potential applicability of RF-DNA fingerprinting using operationally collected signals.