Continuous time-delay chaotic system is the infinite dimensional system which can produce several positive Lyapunov exponents

so such system can produce complex time sequences.This character make it suitable to be applied to secure communication.Based on this analysis

in this paper we first research on the identification of C parameter in M-G hyperchaotic system and propose a new method of identifying C parameter in M-G system.Secondly we attempt to modulate C parameter of this system using the message signal in the transmitter

and at the receiver the message signal is demodulated by using our method of parameter identification.Thus we realize the secure communication.The numerical simulations show that the proposed method can demodulate the message signal well when the convergence time of identification is smaller than the duration of the digital signal.