In order to improve the security of secure communication, a new Generalized Hybrid Dislocated Function Projective Synchronization (GHDFPS) based on generalized hybrid dislocated projective synchronization and function projective synchronization was researched by Lyapunov stability theory and adaptive active control method. At the same time, the control methods of GHDFPS between two different-order chaotic systems with uncertain parameter and parameter identification were presented, and the application of the novel synchronization on secure communication was analyzed. By strict mathematical proof and numerical simulation, the GHDFPS between two different-order chaotic systems with uncertain parameter were achieved, the uncertain parameter was identified. Because of the variety of function scaling factor matrix, the security of secure communication has been increased by GHDFPS. Moreover, this synchronization form and method of control were applied to secure communication via chaotic masking modulation. Many information signals can be recovered and validated.

Concerning the output error model, order identification and parameter estimation were integrated and extended, and the determinant ratio method based on the auxiliary model was put forward. The system order and parameter estimation were got simultaneously with this method, so it could reduce calculation time in the process of system identification. Considering the inaccuracy of the determinant ratio method, a model validation method was proposed to enhance the identification ability. At last, the simulation indicates that the expended determinant ratio method effectively estimates the system order and parameters.

To remove hidden risks and solve neglected Denial-of-Service (DoS) attacks in the back-end database in current low-cost Radio Frequency Identification (RFID) authentication protocols, a new anonymous bidirectional RFID authentication protocol based on low-cost tags was proposed, and the performance analysis was conducted. According to the simple operative logic and shielded operation of reader, this scheme was designed by utilizing two cascading 16 bit Cyclic Redundancy Check (CRC) messages as mutual authentication factor between the label and the reader. The analytical results show the proposed protocol possesses untraceability, authenticity and usability and resists replaying attack and synchronization attack. Overall, it is a RFID low-power security authentication scheme of security, efficiency and practicality.

To handle the problem of low consistency between the objective and subjective evaluations of image fusion, considering the features of Human Visual System (HVS), a new metric to evaluate the quality of the fusion image based on the Visual Attention Mechanism (VAM) and the regional structural similarity was proposed. This quality metric utilized the global salience got by VAM and the local salient information to estimate how well the salient information contained within the sources was presented by the composite image. Since human eyes are more sensitive to region, by giving higher weight to those regions with high saliency value in the source images, the new metric evaluated the quality of the fused image by computing the weighted regional structural similarity of the fused image and source images in all regions. The correlation analysis between objective measure and subjective evaluation was performed and the results demonstrate that the new metric is more consistent with human subjective evaluation, compared with the traditional objective measurements and the widely used EFQI.