Radio Frequency fingerprints (RFF) authentication is one of the methods for the physical-layer information security, which uses the hardware characteristics of the transmitter to identify its real identity. In order to improve the performance of RFF based on preamble with fixed duration, a nonlinear RFF authentication method based on payload symbols is proposed for the wireless OFDM devices with the bit mapping scheme of QPSK. The communication system is modeled as a Hammerstein system containing the nonlinear transmitter and wireless multipath fading channel. A parameter separation technique based on orthogonal polynomial is presented for the estimation of the parameters of the Hammerstein system. The Hammerstein system parameter separation technique is firstly used to estimate the linear parameter with the training signal, which is used to compensate the adverse effect of the linear channel for the demodulation of the successive payload symbols. The demodulated payload symbols are further used to estimate the nonlinear coefficients of the transmitter with the Hammerstein system parameter separation technique again, which is used as the novel RFF for the authentication of the QPSK-OFDM devices. Numerical experiments demonstrate that the proposed method is feasible. The novel method can also be extended to the OFDM signals with other bit mapping schemes.
翻译:无线电频率指纹(RFF)认证是物理级信息安全的一种方法,它使用发射机的硬件特性来确定其真实身份。为了根据具有固定期限的序言改进RFF的性能,建议对带有QPSK比子绘图仪的无线 OFDM 设备采用非线性RFF 认证方法。通信系统建模为Hammerstein 系统,其中包含非线性发射机和无线多路衰减通道。在估计Hammerstein系统的参数时,介绍了一种基于正方位多线性分解技术。Hammerstein系统参数分离技术首先用来用培训信号来估计线性参数,用于补偿连续有效载荷符号降压线性通道的不利影响。演示有效载荷符号还被进一步用于估计发报机的非线性系数,而Hammerstein系统参数分离技术又用作新型RFF,用于认证QPSK-OFDD装置的参数。Nummericalalalal 实验显示,拟议的方法也可用于BBDM计划。