Kamil, I. A.Fakolujo, O. A.2018-10-092018-10-09201017th International Conference on Systems, Signals and Image Processing, IWSSIP 2010ui_inpro_kamil_chaotic_2010http://ir.library.ui.edu.ng/handle/123456789/1672in-proIn recent years, chaotic secure communication systems have attracted significant interest due to their higher unpredictability over conventional secure communications systems and simplicity of implementation. This study presents the modeling of four chaotic modulation techniques. The techniques are Chaotic Masking (CM), Chaos Shift Keying (CSK), Chaos On-Off Keying (COOK), and Differential Chaos Shift Keying (DCSK). Simulations were carried out using Simulink in Matlab environment to implement these techniques. A qualitative evaluation of the transmitted signal waveforms in all the cases considered showed that DCSK gives the highest level of security followed by CSK while COOK gives the least level of security. The data transmission rate of the other three techniques was however twice that of DCSK.enOther