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 1 Modulation and Encryption of ECG Signal

Input Biomedical signal

E C G

, Chaotic signal

c S

, Modulation order M
Output Modulated signal

m S

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procedure Preprocess_Encrypt_Signal
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def $M = n$ - $Q A M$
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$eS \leftarrow E C G + c S$ ▹ ECG signal combined with chaotic signal
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$sN \leftarrow []$ ▹ Initialize the normalized signal array according to the n-QAM order
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for each $e S_{i}$ in $eS$ do
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$s N \leftarrow \frac{e S_{i} - m i n (eS)}{m a x (eS) - m i n (eS)}$
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end for
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return sN
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$sD \leftarrow []$ ▹ Initialize the discretized signal array
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for each $s N_{i}$ in $sN$ do
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$sD \leftarrow floor (s N_{i} \cdot {(M - 1)}^{2})$ ▹ Signal rounding and conversion to complex signal
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end for
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return $s D$
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ECG_ds ← {real(sD), imag(sD)} ▹ Decomposition of the signal
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$mS \leftarrow n - QAM (ECG_ds, M)$ ▹ Modulation of the encrypted signal based on the n-QAM order
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return $mS$
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end procedure