Chaotic communications using nonlinear transform-pairs

We describe a general chaotic communication system with nonlinear transform-pairs and saw-tooth functions. Some chaotic communication systems can be deduced from this general model. It provides an approach for encryption and decryption by setting nonlinear transform-pairs as the keys in the sender and the receiver. Simulation results of several such chaotic communication systems with direct and parameter modulations are presented. Both modulation methods can be used to transmit signals and noise disturbed Gaussian channel. The parameter modulation method provides the feasibility to transmit multiple signals simultaneously over a single channel; with a 40 dB Gaussian noise in which the extended Kalman filter (EKF) is used.