Previously, researchers utilized the advantages of self synchronizing properties of chaotic oscillators to transmit the secret messages. However, researchers performed synchronization considering ideal scenarios where the received waveform is an exact replica of the transmitted waveform. Considering these practical limitations, we developed a scheme to recover the secret message even when the transmitted waveform experiences the losses such attenuation effects that are apriori and may be caused due to channel effects.
To demonstrate, we construct two Lorenz chaotic oscillators, where the first oscillator is the driver circuit and second is the response circuit. A secret message is embedded on one of the state variables of the driver circuit that generates and transmits an RF waveform. Now, the received waveform is an attenuated version of the transmitted waveform that is used to drive the response circuit until it is synchronized with the dynamics of the driver system. The response circuit is modeled in a way that it accepts the attenuated version of the transmitted waveform. Once the response circuit is synchronized, the chaotic state variable from the received waveform is removed using the synchronized version there by recovering the message.
Due to the low precision components used between the circuits and due to the parasitic components in the proto-board, the recovered secret message might be the noisier version of the original message. This issue can be improved by implementing the circuits with high precision components and solder them on PCB.