Enhancing Security of Telemedicine Data: A Multi-Scroll Chaotic System for ECG Signal Encryption and RF Transmission

. 2024 Sep 14;26(9):787. doi: 10.3390/e26090787

Algorithm 3 Post-processing of received signal.

Input Received signal

E C G_{R X}

, Transmitted signal

E C G_{T X}

, n-QAM order M
Output Encrypted signal

E C G_e n c r y p t

1:
procedure Process_Received_Signal
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$R X_s y n \leftarrow synchronize (E C G_{R X}, E C G_{T X})$
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$R X_r o t \leftarrow R X_s y n \cdot exp (i \cdot θ)$ ▹ Rotation in the complex plane
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$R X_f \leftarrow filter_design (R X_r o t)$
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$demodS \leftarrow qamdemod (R X_f, M)$
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ECG_complex ←{real( $d e m o d S$ ), imag( $d e m o d S$ )}
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$ECG_d \leftarrow []$
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for each $E C G_c o m p l e x_{i}$ in $ECG_complex$ do
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$E C G_d \leftarrow \frac{ECG_{complex}_{i}}{{(M - 1)}^{2}}$
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end for
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return $E C G_d$
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$ECG_encrypt \leftarrow []$
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for each $E C G_d_{i}$ in $ECG_d$ do
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$E C G_e n c r y p t \leftarrow E C G_d_{i} \cdot (\max - \min) + min$
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end for
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return $E C G_e n c r y p t$
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end procedure